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February 10

djvu viewer

HI! I know VuDroid but I have to install it on sort of IPad and I cannot use QR or direct download, I have to download an apk and move it to a micro SD in order to install it. Can you help me? --83.103.117.254 (talk) 09:36, 10 February 2011 (UTC)[reply]

On an iPad, or not? ¦ Reisio (talk) 10:43, 11 February 2011 (UTC)[reply]

how to use ir sensors...

i wanted to use an ir sensor in an application.. so wat is the minimum voltage can sm0038(ir sensor) produce ? where can i get the data sheet? can it produce atleast .2 volts? — Preceding unsigned comment added by Girishkakalwar (talk • contribs) 13:03, 10 February 2011 (UTC)[reply]

Google tells me that the SM0038 is produced by Vishay. They have many IR sensors. All of the sensors I've seen from them have an operating voltage of 5v (with about 1v variance). However, it shouldn't matter what the actual output voltage is. It is enough to control a transistor or be the input for a logic IC. You shouldn't be attempting to use the ouput voltage of a sensor as the power for another device. -- kainaw ™ 13:59, 10 February 2011 (UTC)[reply]

Some people seem to consider its is about the same as the TSOP1738 and for that the VO rage is given as –0.3...6.0 --Aspro (talk) 14:14, 10 February 2011 (UTC)[reply]

Livescribe Pulse Smartpen

Resolved

I have a 4GB Livescribe Pulse Smartpen but no docking station, cables, cd drivers or anything else. The pen is also in slightly bad condition. Since I can't use it and it cost me nothing, I'm wondering if there is any way I can extract the 4GB inside it and use it for something else. Is that possible? And how much might I be able to sell just the pen part for, or would no one be interested without the docking station part to go with it? 82.43.92.41 (talk) 16:40, 10 February 2011 (UTC)[reply]

Do you mean that you want to desolder the flash memory chip from the pen's internal circuitry, and try to attach it to something else? Sure, this is certainly possible, and a technician skilled in working with PCBs could probably do it. If the memory is undamaged, you might be able to reconnect the chip to another controller that could actually use it. Consider that 4 GB SD cards, which use essentially the same technology, cost around $20, which is less than the labor for the technician would cost, and guaranteed to work. It is an unfortunate fact of economics that modern consumer electronics are one-shot disposable items. In almost all cases, buying a brand-new unit is cheaper than repairing or servicing the old unit, let alone salvaging parts from it. Nimur (talk) 18:22, 10 February 2011 (UTC)[reply]

Thanks 82.43.92.41 (talk) 18:44, 10 February 2011 (UTC)[reply]

Huggle with Wine

Hello. I am a Ubuntu user, and I have am trying to use Huggle with Wine. However, when I open it with Wine, it says it is loading, and there is a "starting Huggle" notice, which then disappears, and nothing else happens. Any reason for this? --T H F S W (T · C · E) 18:39, 10 February 2011 (UTC)[reply]

I've probably spent about 200 hours with Linux over the course of 20-30 attempts at switching to it from Windows and Mac, and from what I gather this is the standard Linux experience. Treat it as an adventure game -- for the most genuine experience, a text adventure game -- and if you really need hints/spoilers/walkthroughs you can ask the developers, who hang out on IRC. You might even get into the Hall of Fame. 109.128.101.244 (talk) 19:43, 10 February 2011 (UTC)[reply]

According to Wine's application database, even if you got it working, it might not work very well. Paul (Stansifer) 14:28, 11 February 2011 (UTC)[reply]

@109.128.101.244 - I don't know much about Wine, but I'm a current user of Ubuntu (on a virtual machine), and I find Ubuntu quite intuitive to use. I don't know what distribution(s) you used during your 200 hours of attempts to switch to Linux, but IMHO Ubuntu 10.04 is the best linux distribution in existence, and beats the buggy Windows Vista hands-down. Rocketshiporion ♫

Need a piece of software to help with statistical research on speedy deletions

Hey, I wanted to post this on Wikipedia:Bot requests when I saw a mention that posting it here might be faster.

I am looking for a piece of software (or multiple pieces) which can help me do the following:

read the special:Newpages feed and retrieve for every article the title, number of edits the creator has and whether he is autoconfirmed. I think this has to be done live, as deleted pages disappear from the feed.
read the deletion log and retrieve for every page which is also in the first list the deletion rationale. This can be done in one big go several weeks after the first list is created
Combine this into some table either on or off wiki on which I can perform statistical analysis.

The background behind this is that around 75% of articles created by new users is speedily deleted, which alienates potential new edits and is very wp:BITEy. 75% is only a rough guess however and some decent statistics would help to gain more insight in how the speedy deletions process could be improved. Yoenit (talk) 21:23, 10 February 2011 (UTC)[reply]

(Dare I suggest that one might have to look at the content of said deletions rather than the raw numbers? A high percentage means nothing unless you know the number of false positives. It may very well be that 75% of all articles created by new users are blatant spam, mistakes, or vandalism.) --Mr.98 (talk) 21:39, 10 February 2011 (UTC)[reply]

Hence the need for the deletion rationale. It will allow for sorting by speedy reason (manually unfortunately), so all the spam, vandalism and hoax junk can be isolated. If it turns out that 75% of all pages created by new users is spam, I would propose moving up the page creation right to autoconfirmed, but I would need proper statistics before suggesting that. Yoenit (talk) 21:53, 10 February 2011 (UTC)[reply]

It seems more reasonable to do this by hand. Just take a few random moments, note the top article on the Newpages list, then check an hour (or a day) later to see whether it has been deleted. A sample of 20 randomly chosen moments should give you a decent fix on the percentage. Looie496 (talk) 21:42, 10 February 2011 (UTC)[reply]

I agree with that, but 20's just too small a sample set. I'd argue for 40+. —Jeremy ^{(v^_^v Hyper Combo K.O.!)} 21:45, 10 February 2011 (UTC)[reply]

I did it with 50, which I watched over a period of a month. ~80% deletion rate of pages created by new editors (User:Yoenit/CSD research). I want more data so I can say stuff about the reason and method of deletion as well. Yoenit (talk) 21:53, 10 February 2011 (UTC)[reply]

Wasn't a survey of this type already done at Wikipedia:Newbie_treatment_at_Criteria_for_speedy_deletion?--v/r - T P 22:25, 19 February 2011 (UTC)[reply]

Qualcomm BREW

I've been looking around and there seem to be a few device-specific "jailbreaks", if you will, for Qualcomm BREW devices that either:

allow one to run unsigned Java apps.
allow one to run unsigned BREW apps.

But I have come across very few methods of doing this. I have a few questions, your answers may be device-specific for phones between 2007 and now:

Is there anyway I can jailbreak a BREW phone?
How can browse the full EFS (Embedded File System) of a newer BREW phone?
Is it possible to make custom firmware for a BREW phone and are there any custom firmwares that exist?
Qualcomm Product Support Tools are floating out on the web. Are there any versions newer than 2.74 that have been leaked?

--Melab±1 ☎ 23:29, 10 February 2011 (UTC)[reply]

MAC address

How do I change my MAC address running Windows Vista? Wikibooks has an article on how to on XP but not on Vista. Do I have to change it separately from my computer and my router? Thanks. 72.128.95.0 (talk) 23:51, 10 February 2011 (UTC)[reply]

http://www.technitium.com/tmac/index.html 82.43.92.41 (talk) 23:59, 10 February 2011 (UTC)[reply]

Why would you want to change your MAC address? If you don't have a thorough understanding of what you are doing, you can make some pretty nasty things happen by doing that. Looie496 (talk) 23:11, 11 February 2011 (UTC)[reply]

February 11

Apache Tomcat counters

Hi All

can anybody please answer below question.

What are the popular counters available in Apache Tomcat Server. — Preceding unsigned comment added by Ravisana99 (talk • contribs) 05:30, 11 February 2011 (UTC)[reply]

In general, counters are not popular anymore. They are a very useless statistic, so nobody checks them. Instead, a logfile analyzer is used. See Web log analysis software. -- kainaw ™ 14:37, 11 February 2011 (UTC)[reply]

Why do Alarm Clocks sometimes not ring?

Various alarm devices (simple alarm clock, simple digital watches with alarm functions, iPod touches) will occasionally not ring their alarm at all in the mornings even when the settings have no been changed at all and their batteries are properly charged. Why does this happen? Acceptable (talk) 07:51, 11 February 2011 (UTC)[reply]

I know iPod Touches will not ring if your sound is not turned up. As for the others, maybe you were doing something then so it failed? General Rommel (talk) 08:13, 11 February 2011 (UTC)[reply]

Apart from true alarm clocks, most devices have a very quiet alarm. I suspect you are just not hearing it, unless it's an iPhone, in which case it really doesn't always work[1].--Shantavira|^{feed me} 10:54, 11 February 2011 (UTC)[reply]

A common problem on cheapie alarm clocks is that the rheostat which controls the volume goes bad, causing it to seemingly randomly switch between loud and too quiet to hear. If you have it set to radio alarm, then the same problem with the tuning "pot" can also cause it to go off-station, which may be quitter or louder, depending on how it handles static. StuRat (talk) 08:27, 15 February 2011 (UTC)[reply]

In the category of user error, having AM and PM mixed up (either on the time setting or the alarm setting) can cause it to go off when you are away, thus making it seem like it's not going off at all. StuRat (talk) 08:29, 15 February 2011 (UTC)[reply]

nokia 1280 ringtone

i am in india, I have a nokia 1280 and I have an mp3 file on my computer i would like to have as the ringtone. does anyone able to tell me how i can set this up??Thanks 117.241.122.68 (talk) 09:08, 11 February 2011 (UTC)[reply]

According to the Nokia 1280 support page for India, that phone supports mp-3 ringtones but has no means to load/manage mp-3 files through a data cable, bluetooth or infra-red. I'm not even sure it can accept ringtones sent to it from a company that sells ringtones. If you consider buying your desired ringtone and getting it sent via SMS, check that it is compatible with your phone first... the people who run that kind of business generally don't give refunds. Astronaut (talk) 12:52, 11 February 2011 (UTC)[reply]

sql in c

i read in a book that if you include stdlib you can execute sql statements simply typing 'exec sql' before 'em after connecting with 'connect to user@dbname'. But dbname is the host or the instance? And the Password? Thanx --83.103.117.254 (talk) 09:34, 11 February 2011 (UTC)[reply]

It sounds like your book described some nonstandard pre-processor directive or macro. It's possible that it was also suggesting that you use system() to exec a sql program externally. Normally, in C, to execute database commands, you must use a database connection library. For example, take a look at the MySQL C API provided by the mysqlclient library. Several Embedded SQL compilers exist as well; some can even abstract away the database connection library. However those compilers are not strictly compilers for the C programming language (and many are proprietary, non-free tools). Check your book carefully; it's possible they explained a toolchain setup, or explained that the SQL statements were expressed in pseudocode to avoid the details of any specific database API. Nimur (talk) 10:53, 11 February 2011 (UTC)[reply]

The question is very likely about Pro*C. How to use it depends on your development environment - would that be some version of Microsoft Visual Studio? Oracle probably has an example project for Visual Studio... 130.188.8.11 (talk) 12:38, 11 February 2011 (UTC)[reply]

For example, both Ingres (example) and its relation PostgreSQL (example) offer an embedded SQL compiler to transform embedded SQL into calls to the regular C API; you then take the C program this yields and compile it with the C compiler. PostgreSQL's program for doing this is called ecpg. As to the specifics of the particular database ESQL you're talking about, you'd need to look in the documentation for that specific database and its toolset; they're not very standardised. -- Finlay McWalter ☻ Talk 12:38, 11 February 2011 (UTC)[reply]

A heuristic autoplaying bot that can defeat Lone Wolf on Halo: Reach - Exists?

Or possible to program?

Halo: Reach's Lone Wolf mission appears to be the most epically unbeatable level I have ever come across of any video game in recent memory. It appears unwinnable to human players.

Therefore, with the orders-of-magnitude quicker thinking of autoplaying bot-scripts, if equipped with a heuristic subroutine, then it should learn from its mistakes and improve upon its own strategies every time it dies or even takes a hit from enemy weapons.

With its self-adapting abilities, I could keep it on for a week (or even many months if necessary), and enable it to save its own updated tactical and strategic subroutines every 30 minutes in case of a power failure.

Some have claimed that "it was not designed to be won," so then the bot will learn how to violate those design parameters!

Now, some questions:

1. Does such a self-adaptive autoplaying bot already exist, that can play Halo: Reach?

2. If so, how do I put one together?

3. How quickly could it potentially learn to get better?

4. From this, could anyone extrapolate how well it would do after running for a week?

5. ...after running for a month?

6. What is the size of the entire Covenant and/or Flood Army that is deployable to Reach?

7. How many soldiers arrive in a single wave of reinforcements, and how often do those waves arrive?

8. Therefore, after calculating the waves of reinforcements and total army sizes, how long would a bot need to take in order to singlehandedly defeat every last possible wave of reinforcements, therefore wipe out their entire army, thus win the Lone Wolf battle of Reach?

9. If I arranged to hook up the bot and game to the fastest supercomputer in the world, how much quicker would it be able to win Lone Wolf? --70.179.187.21 (talk) 09:47, 11 February 2011 (UTC)[reply]

To write a bot, your game usually needs to present a software development kit (SDK), which exposes a set of game features and data for your bot to process. Then, you'd design algorithms to work with the data that the game provides. It doesn't look like Halo's development studio or publisher has ever released an SDK to the public; so there's no practical, realistic way for you or anyone to design a bot. Theoretically, you could design a computer-vision system that watches your monitor, analyzes the gameplay, and produces commands to the controller - but in practice, that would be prohibitively difficult. Theoretically, you could also reverse-engineer the game's binary distribution and hook your bot into that, but this is pretty infeasible. One reason a game studio chooses not to provide a bot SDK is because it is extremely difficult to release one that would prohibit "cheater-bots." In a sense, providing the necessary data would make it possible for you to write a perfect bot; and it'd be entirely up to you to add "imperfections." Have a look at this article, Analyzing the AI Bot Library from the Quake 3 Source Code. Nimur (talk) 11:08, 11 February 2011 (UTC)[reply]

If the level is not designed to be one, then there is probably no victory condition. What makes you think that there is a "last possible wave of reinforcements"?

I haven't played it, but If the level is designed to be unwinnable, the developers probably just put the reinforcements on an infinite loop. APL (talk) 15:22, 11 February 2011 (UTC)[reply]

I assume he knows that, that's why he's saying he would calculate the maximum possible reinforcements (in an in-universe way I assume) and just "call it good" once he'd killed enough spawned enemies to exceed that number. Look at it this way, if you had a "supposed to lose" fight with infinite respawns in a WWII game, once you've killed as many NPCs as the entire population of Germany, Japan, Italy and Austria in 1939, you could reasonably assume that the outcome of the fight was 'winning the war singlehandedly'. 65.29.47.55 (talk) 21:59, 11 February 2011 (UTC)[reply]

Note that it would probably be easier to hack the game/console in some way so that you do not take any damage, than it would be to build a bot. The former issue is just finding what variable contains your health meter and keeping it untouched. (I don't know how you'd do this, mind you.) The latter involves developing complicated AI. --Mr.98 (talk) 16:48, 11 February 2011 (UTC)[reply]

Learning is a super difficult problem in the general case. Filtering out irrelevant information is something humans can do easily, but we have no idea how to systematize it. Without a way to discard irrelevant information, a learning AI is left doing hill climbing in a heavily multidimensional space; it'll get stuck at a local maximum (it'll probably make it there really quickly) and never improve after that. (I'm not an AI expert at all, so there may be some approaches I'm missing, but I've never heard of anything like the kind of learning humans do.)

Supercomputers probably wouldn't be any use for playing games; they consist of many many CPUs that are each not very much more powerful than the CPUs in a desktop machine. Data parallel problems can be solved in hours instead of years this way, but a task like this doesn't lend itself into being broken into little bits that can be executed independently. Paul (Stansifer) 00:35, 12 February 2011 (UTC)[reply]

Changing a wiki logo

I have a PMWiki website; how can I change the logo that is in the top left? 128.223.222.68 (talk) 18:29, 11 February 2011 (UTC)[reply]

Looks like you have to set a variable in PmWiki; see the variables page. ---— Gadget850 (Ed) ^talk 18:59, 11 February 2011 (UTC)[reply]

Once you determine the address; i.e. in what directory, etc. the original logo is currently, kept, all you really need to do is rename that logo, to say logo.old, and then upload a new one to the same location. This can be a little less daunting for a newbie than resetting the location in one's localsettings.php file, for which you need server access. ^Д-р_{СДжП,ДС} 21:36, 11 February 2011 (UTC)[reply]

ReferencePreservingDataContract in WCF calls

Today at work, I just solved a problem in fifteen minutes that had been troubling our customer for days. They had reported that whenever they try to access a certain feature of our application, they get an error message instead. It turned out that this feature was calling a WCF method, and the object returned had cyclic references, so the call crashed. I solved it simply by adding [ReferencePreservingDataContract] to the WCF interface, which allows the WCF call to return objects with cyclic references. But why isn't this enabled by default? What's the harm in using it? JIP | Talk 18:55, 11 February 2011 (UTC)[reply]

Connecting keyboard + monitor to a smartphone

Can you connect both to your smartphone? I know that connecting normal keyboards shouldn't be a huge deal, since it can be done through bluetooth. But is it always possible? (provided the phone has bluetooth). — Preceding unsigned comment added by Wikiweek (talk • contribs) 20:22, 11 February 2011 (UTC)[reply]

Depends on the phone, as far as I'm aware the iPhone's bluetooth supports ONLY headsets. Droid is obviously a much more open platform, can't speak for windows. Caveat: that may be outdated information I haven't looked into the latter generation iPhones since the android platform came out. 65.29.47.55 (talk) 22:02, 11 February 2011 (UTC)[reply]

The existence of bluetooth keyboards doesn't mean you'll be able to connect it to a bluetooth phone. But, in the case of Android, seems normally possible to do that. The case of the monitor is more tricky, since you'll be moving loads of data through it, and do not only need a connection, but also a good graphic card. AFAIK, no smartphone has this capability. Quest09 (talk) 12:30, 12 February 2011 (UTC)[reply]

You might be interested in the Motorola Atrix that comes with a dock for connecting a monitor and USB keyboard (or bluetooth) and mouse to it. It also has a laptop dock with build in monitor, keyboard, and mouse and a special mode for when it is docked that gives a full firefox browser with flash support.--v/r - T P 22:39, 19 February 2011 (UTC)[reply]

February 12

Change language of OpenProj?

I eagerly downloaded and installed OpenProj after reading about it here, only to find that it defaulted to Simplified Chinese for all menus and dialogs. That is indeed my geographic locale, but I'm using an English copy of Windows XP. I can find no option/preference setting to change the language. A google search only uncovered other people with the same problem. This is quite irritating! Can someone help me force OpenProj to display in English? The Masked Booby (talk) 03:19, 12 February 2011 (UTC)[reply]

Maybe if you change your locale to somewhere English, maybe it will display in english. General Rommel (talk) 06:50, 12 February 2011 (UTC)[reply]

The solution given here http://sourceforge.net/p/openproj/feature-requests/117/ (second post by Barberousse) worked for me. The system language of the Windows on my computer is Russian. I replaced the content of openproj.bat file, which is in the Open Proj work directory, with this code: "java -Duser.language=en -Duser.country=US -Xms128m -Xmx768m -jar openproj.jar". Then I just launched openproj.bat (to do it you need to right-click on the file and choose "Run" from the context menu) and enjoyed the interface in English. Good luck! dancingyogi (talk) 06:53, 10 October 2013 (UTC).[reply]

AES-256 Encryption Parallellism

Resolved

Hello RefDesk volunteers,

I want to know whether data encryption is a primarily serial or parallel processing task, i.e can data encryption be executed faster using e.g. twelve CPU cores compared to a two CPU cores? The encryption method of interest here is AES-256, using a password with a length of between 12 and 20 characters.

Thank you! Rocketshiporion ♫ 12:36, 12 February 2011 (UTC)[reply]

If you mean performing a single encryption on multiple cores, it's very difficult to properly parallelise most symmetric encryption functions, as they display the avalanche effect very strongly (quite deliberately - that's from where much of their security is derived). This is especially true if the underlying cryptosystem involves a chained inter-block dependency (e.g. CBC mode); non-chained modes (e.g. ECB) can be parallelised, but they're less frequently used, as they have poorer security characteristics. The most common strategy to increase throughput of such a cipher is to vectorise the computation, where each stage of the computation is handled by a different computational element. For the operations done by AES, CPUs are a poor choice to handle vectorisation, as the cost of handing off each block to another core (and the consequent loss of register and cache coherence) dominates the relatively minor cost to actually computing each phase. High-performance calculation of ciphers like this is typically performed by an ASIC, where vector stages are physically and logically adjacent to one another, making the handoff inexpensive. Where CPUs are used to do bulk AES it's to perform unrelated operations; a password cracker (where each attempt is essentially unrelated to, and not dependent upon, other attempts) fully exploits the parallelism available. -- Finlay McWalter ☻ Talk 15:29, 12 February 2011 (UTC)[reply]

In short, yes, if...

you have more than (block size × number of processing units) = (16 × 24) = 384 bytes of data to encrypt (or decrypt), and
the mode of operation your program uses can be parallelized.

For example, TrueCrypt is able to take advantage of additional CPU cores, since it usually encrypts (and decrypts) megabytes of data at a time and uses the XTS mode of operation, which is parallelizable. 118.96.166.75 (talk) 03:16, 13 February 2011 (UTC)[reply]

CTR mode is fast, embarrassingly parallel, and secure as long as you authenticate the decrypted message. XTS is a bit slower and more complicated; it has advantages in full-disk encryption but there's no need to use it for ordinary streaming encryption. I don't know what 7-Zip uses. Note that AES doesn't define any way of encrypting a file with a password; everybody has their own way of doing it. -- BenRG (talk) 22:11, 13 February 2011 (UTC)[reply]

Objective C Pointers

When working on programming, I came upon a question. Whenever I'm creating an NSString just with stringWithFormat, I have to make the variable a pointer variable (i.e. it has the asterisk), as in:

NSString* myString = [stringWithFormat:@"this is a string"];

However, if I'm creating an NSRange, it doesn't need to be a pointer variable, as in:

NSRange range = [myString rangeOfString:@"this"];

So what I want to know is, Why do I need the asterisk with NSString variables, but not with NSRange variables? --Thekmc (talk) 14:00, 12 February 2011 (UTC)[reply]

Anyone? --Thekmc (talk) 22:08, 12 February 2011 (UTC)[reply]

According to this page, an NSString is an object, but an NSRange is only a struct. Looie496 (talk) 05:09, 13 February 2011 (UTC)[reply]

So your saying that if I am creating an object, I need to make a pointer to it, but if i'm making something that is essentially a C type (like a struct) I don't need to make it a pointer? --Thekmc (talk) 21:43, 14 February 2011 (UTC)[reply]

What flavor for Puppy Linux?

If you have to install a Linux program that comes in the Ubuntu, Debian, Fedora and SUSE flavors, which one is the most likely to fit? Quest09 (talk) 14:03, 12 February 2011 (UTC)[reply]

You should search for one for Puppy Linux first. Then, if you can't find it, use woof on the Ubuntu binary package. -- kainaw ™ 16:21, 12 February 2011 (UTC)[reply]

The only logical reason to use Puppy Linux is if you have a hard drive so small you are literally stuck in the late 80s or earlier. ¦ Reisio (talk) 03:41, 13 February 2011 (UTC)[reply]

Maybe the OP likes puppies? --Ouro (blah blah) 09:22, 13 February 2011 (UTC)[reply]

Reisio, perhaps you have only tried to run Linux on a system that you might be able to call a "personal computer." However, one of the most powerful features of Linux is the ability to run it on other platforms - many which do not even have a hard disk drive. I can list off a few dozen reasons why one might want a tiny version of Linux. I do not think it's fair to call that "1980s technology" - especially because Linux didn't exist in the 1980s. At the very least, this is 2010s technology.

Quest09, you might find a Debian package (.deb) the easiest to install on Puppy Linux. Alternately, you can compile from source-code - a lot of your favorite Linux programs will provide freely licensed source code, to help portability to different types of computers and operating systems. Nimur (talk) 20:59, 13 February 2011 (UTC)[reply]

Yes, broad architecture support is a feature of "Linux", but not Puppy Linux. I can also list off a few dozen reasons why one might want a tiny version of Linux, which is why I stated the only reason to use Puppy is if your primary concern is that it fit on hardware so ancient as to have incredibly low storage capacity — I was referring to hardware from the late 80s, not software. ¦ Reisio (talk) 16:00, 14 February 2011 (UTC)[reply]

Friends, don't quarrel over something as nice and as useful as Linux. I use Fedora. --Ouro (blah blah) 17:20, 14 February 2011 (UTC)[reply]

3d or 3d?

If you have two 3d pictures , but in one case you can turn it, and in the other case, just look at it from one specific angle, how do you call this difference? Both are 3d and none is real, but one has more 3d in it. Quest09 (talk) 16:08, 12 February 2011 (UTC)[reply]

Are you meaning 3-D holographic for the one that you can turn? --Aspro (talk) 17:16, 12 February 2011 (UTC)[reply]

No, just a 3d object on a normal screen. But, one that can be virtually turned around. Quest09 (talk) 18:30, 12 February 2011 (UTC)[reply]

Are you talking about postcards in space, also known as "2.5D"? In other words, one of the images can be rotated, but looks like a postcard once it is rotated enough?--Best Dog Ever (talk) 19:41, 12 February 2011 (UTC)[reply]

No, I'm asking about two quite simple 3ds: imagine you drew a cube with Blender. You can rotate the cube on 3 axis. And now, imagine you drew a cube with GIMP. They are different, even if the GIMP image is a 3d drawing. Do you know what I mean? Quest09 (talk) 20:51, 12 February 2011 (UTC)[reply]

The one that is not really a 3D model is just a Graphical projection. --Mr.98 (talk) 21:21, 12 February 2011 (UTC)[reply]

Well, anything rastered to screen is also a graphical projection. It just so happens that software like Blender, which stores a complete 3D geometry for each (x,y,z) point, has the algorithmic capability to render many different projections from arbitrary view-angles and distances, while a hand-drawn projection is a "one-shot" deal that is a fixed, 2D set of (x,y) geometries. There are intermediate models, too: sophisticated computational geometric models exist that can be rendered from multiple view-angles, without being a complete 3D representation of the object from all view angles. Geometric modeling or 3D modeling might be a useful read. We also have solid modeling, surface modeling, point clouds, and many other interesting ways to describe 3D objects to a computer. In general, it is prohibitively expensive (uses too much memory) to store every point of a 3D object (in fact, it is theoretically impossible: at best, we can sample a quantized subset of the object's geometry). So computer scientists have come up with thousands of clever tricks to reduce the complexity of the model while still producing a high-quality raster representation for some particular use. Nimur (talk) 21:27, 13 February 2011 (UTC)[reply]

Sporadic wireless connectivity

I am havign trouble connecting to my wireless network. I have an XP with a RealTEK wireless adapter. Every few seconds it will go to full bars/"Excellent" signal, but then it will go back to "Not connected", then back to Excellent signal, and so on. This happens whether I use the driver that came with the hardware or Windows to configure it. It always says "Acquiring network address" when it is at "Excellent" and sometimes I can access the internet briefly, but it always goes back to "not connected"/all red. Why is this, and how do I fix it? 72.128.95.0 (talk) 17:18, 12 February 2011 (UTC)[reply]

The problem doesn't necessarily lie with your computer and/or configuration. Are you able to check the same wireless network on a different computer? What is the behaviour then? --Ouro (blah blah) 18:29, 12 February 2011 (UTC)[reply]

Multi-threaded Data Compression

Hello again,

I'm currently using 7zip to make compressed and encrypted data backups. My compression method of choice is LZMA, with a 1024MB dictionary size and 256-byte word size using the maximum of 4 CPU threads. My chosen encryption method is AES-256 with a password which is between 12 and 20 characters in length. I have two six-core processors, each of which support twelve cores, and would like to use all 24 threads to compress and encrypt data. So my question is as follows: does a software product exist which fulfils the following requirements?

Compresses data using the LZMA method with a 1024MB dictionary and 256-byte word size.
Supports a minimum of 20 CPU threads for use in data compression.
Encrypts data using the AES-256 algorithm.

Thanks. Rocketshiporion ♫ 18:12, 12 February 2011 (UTC)[reply]

I'm pretty sure nothing there is will meet those standards, because hardly anyone has 24 CPU threads and out of those few even fewer probably wish to use them for data compression. The only thing that you might want to give a shot is asking a programmer whether he can write a mod/plugin for 7zip that allows it to use all of your threads...--87.79.212.251 (talk) 20:32, 12 February 2011 (UTC)[reply]

Does any software exist which can do LZMA compression using anything more than four CPU threads? Rocketshiporion ♫ 21:18, 12 February 2011 (UTC)[reply]

Take a look at this article, especially its comments section. Apparently, LZMA is not very parallelizable. One way to parallelize it more would be to break the data into several chunks and compress them independently, but that will hurt the compression a lot. 118.96.166.75 (talk) 03:00, 13 February 2011 (UTC)[reply]

LZMA appears to be yet another LZ77 variant, and LZ77 variants are normally highly parallelizable because the dictionary at any point is just the last n bytes of the file. LZMA probably has some additional context for the range coder, and you would lose some compression ratio if you periodically flush that, but you don't have to throw away the 1GB dictionary. Some comments in the linked thread make me think that Igor Pavlov might have neglected to provide a way to flush the range-coding context in the file format. In that case a change to the format would be needed, or a custom decompressor. But that would be nothing to do with the algorithm itself, it would just be an oversight in the file format. -- BenRG (talk) 21:11, 13 February 2011 (UTC)[reply]

One more question: is there any software which can do data compression (with any other algorithm) using anything more than four CPU threads? Rocketshiporion ♫ 19:38, 13 February 2011 (UTC)[reply]

I believe 7-zip will efficiently use arbitrarily many cores for bzip2 compression. This has no cost in compression ratio because bzip2 independently compresses 900,000-byte chunks even when single threaded. But that means that bzip2 does poorly on files that benefit from a huge LZ dictionary (such as full Wikipedia dumps), so it probably won't meet your needs.

There's a parallelized xz called pxz, but (based on the extremely limited documentation) it appears to just divide the file into chunks, without sharing dictionaries. -- BenRG (talk) 21:30, 13 February 2011 (UTC)[reply]

Doesn't LZMA2 have better multithread support? That's been in 7-zip beta for ages. I believe the compression is better with less threads however and it may just use chunks. Nil Einne (talk) 16:02, 14 February 2011 (UTC)[reply]

Search engine that ignores robots.txt

Greetings, this will probably make me sound like a complete greenhorn but could anyone recommend a good search engine that pays no attention to robots.txt? Thanks a lot in advance.--87.79.212.251 (talk) 20:28, 12 February 2011 (UTC)[reply]

Just use any search engine, and put

-"robots.txt"

in the search string. Rocketshiporion ♫ 21:25, 12 February 2011 (UTC)[reply]

The questioner is referring to the robots exclusion standard, not a specific query. All search engines are supposed to use it. Many people have written articles that claim Google and Bing (and any other search engine) don't obey the robots.txt file. However, what I see in those complaints is that the robots.txt file is formatted incorrectly and, therefore, ignored. It is not a case of the search engines purposely ignoring all robots.txt files. -- kainaw ™ 21:30, 12 February 2011 (UTC)[reply]

robots.txt is mainly used to exclude things that are dynamic and possibly large and have no value as search results. (For example, things like Special:RecentChanges.) Search engines exclude those things not just to be good citizens of the Web, but also to improve the quality of their results. People don't generally (if they know what they're doing) use robots.txt as a security device to hide things; if they want them hidden, they just need to deny access to the outside world altogether. Paul (Stansifer) 14:16, 13 February 2011 (UTC)[reply]

Ignoring robots.txt would be dangerous! One of the major uses of robots.txt is to ensure that "robots" (web crawlers) do not follow links that contain dynamic content or could cause the server to do a lot of work. For instance, Wikipedia's robots.txt disallows access to /wiki/Special:Search and /wiki/Special:Random, among other pages. Allowing crawlers into the search page would allow them to scrape the search index, whereas allowing them into the random page would cause them to get random content, which would be undesirable. --FOo (talk) 18:00, 13 February 2011 (UTC)[reply]

Yes, that's all great, but it's not helpful at all because I didn't ask why most search engines don't ignore it, but rather which search engines do. I know that robots.txt is not used often to hide things but I am trying to investigate a strand of servers that have popped up and they all did use robots.txt to make it hard for people to locate them via search engines. Sorry to be so frank, but I really need a link, not excuses as to why you don't know of any.--213.168.109.74 (talk) 20:21, 13 February 2011 (UTC)[reply]

We have an article on something called Botseer. Its website seems to be down, but apparently its purpose was to index robots.txt files. There's an archived version of part of the site at [2], but it probably won't be much use for your purposes (it has things like statistics on how many robots files mentioned some well-known bots). Perhaps what you're asking for just doesn't exist: people have asked this question before on other sites and got no useful answers. Perhaps you could be more specific about what exactly you are trying to do, somebody might have ideas about other approaches you could try? 130.88.139.45 (talk) 12:20, 14 February 2011 (UTC)[reply]

I suspect it's unlikely many search engines are going to boast about ignoring robots.txt because it's liable to get them banned by many sites. And the sites themselves know there is limited advantage to ignoring robots.txt. There may be some small obscure search engines that do, but it may not help you if they don't even index these sites or they're banned because everyone knows they ignore robots.txt Nil Einne (talk) 15:52, 14 February 2011 (UTC)[reply]

You could write your own. If you know which servers that you are looking at it's relatively simple process. And, probably quicker than trying to find some obscure search engine that would do that for you.

February 13

QVOD player

My mother is using the QVod player to watch videos and after downloading videos, she is unable to watch any of the videos downloaded. It displays a black screen with the file name on it. It worked earlier yesterday but no longer works. The only change to my computer was the installation of Real Player. My cursory search on Google shows nothing. Could this be a video car problem? Could this be a software problem? What should I do? --Blue387 (talk) 04:15, 13 February 2011 (UTC)[reply]

This might be a video codec problem, but I'm not sure. --Blue387 (talk) 04:31, 13 February 2011 (UTC)[reply]

I have installed the latest version, fixing my problem. Never mind. --Blue387 (talk) 04:46, 13 February 2011 (UTC)[reply]

Have you tried another player? General Rommel (talk) 10:37, 13 February 2011 (UTC)[reply]

Avoiding the double-plug cables with USB bus powered devices.

I have seen portable hard drives, optical drives, and even scanners that get both power and data from a single USB connection. However, most include a Y-shaped cable with two USB type A plugs on one end. The manuals state this is for USB ports that don't provide "full USB power". A user plugs both of them in to get enough power for the device on the other end of the cable. So what is full USB power? And why is 2X low power always enough power? I hate having to deal with special cables. What should I look for when buying a USB hub to make sure each port provides full USB power for each of my devices? --68.102.163.104 (talk) 04:30, 13 February 2011 (UTC)[reply]

If you want to be sure each port of a hub provides enough powr, get a self powered hub (i.e. one that comes with a seperate power adapter that you plug in to the wall) Nil Einne (talk) 05:13, 13 February 2011 (UTC)[reply]

Right. I have one, but apparently it isn't giving bus-powered devices enough power. Which is why I'm asking my original question. --68.102.163.104 (talk) 16:15, 13 February 2011 (UTC)[reply]

You have a self powered hub, ones that includes a power adapter to attach to the wall but it still doesn't provide enough power? This is rather odd, I would suggest the hub is potentially defective. Nil Einne (talk) 15:03, 17 February 2011 (UTC)[reply]

I agree. I would remove all the USB cables and check one of the USB outputs for 5v. I have a USB breakout box I use for this purpose. As to "full USB power", it depends on the device. Universal Serial Bus#Power states "Some devices like high-speed external disk drives may require more than 500 mA of current and therefore cannot be powered from one USB 2.0 port. Such devices usually come with Y-shaped cable that has two USB connectors to be inserted into a computer." I have an older USB 2.5" hard drive that includes a power cable that connects to a PS/2 port— I had to use it on older laptops, but not my current laptop. ---— Gadget850 (Ed) ^talk 15:24, 17 February 2011 (UTC)[reply]

rsync question

Is there an option in rsync to delete all files on the receiver that are not found on the sender? The man page mentioned "--del", is this what I want? JIP | Talk 09:33, 13 February 2011 (UTC)[reply]

It might, as it depends on how you call rsync.

ls /source
foo
bar
ls /destination
foo
ney
rsync -aPv --delete source/ destination/
ls /destination
foo
bar

but:

ls /source
foo
bar
ls /destination
foo
ney
rsync -aPv --delete source/* destination/
ls /destination
foo
bar
ney

-- 78.43.71.225 (talk) 20:07, 14 February 2011 (UTC)[reply]

I assume this is because rsync -aPv --delete source/* destination/ is equivalent to rsync -aPv --delete source/foo source/bar destination/ (in this case), so rsync does not even consider the file ney as part of the backup process? JIP | Talk 07:26, 15 February 2011 (UTC)[reply]

Apple Mac

How do I move a downloaded program from downloads to memory stick please? Kittybrewster ☎ 11:09, 13 February 2011 (UTC)[reply]

There are many different ways, but the simples one is probably to insert the USB stick, open two finder windows (using Cmd-N or "New Finder Window" from the File menu), navigate to the Download folder in one window, to the USB stick in the other (it should be in the sidebar of the Finder window - if not click on the small grey oval in the upper right corner to expand the window), and simply drag the file over from one to the other. --Stephan Schulz (talk) 11:18, 13 February 2011 (UTC)[reply]

[JavaScript] Not a number

In Firebug:

>>> parseFloat('HELLO!');
NaN
>>> typeof(parseFloat('HELLO!'));
"number"
>>> if (parseFloat('HELLO!')==NaN) { alert('NOT A NUMBER!!!') };
undefined

Isn't it kind of stupid that the type of NaN is "number"? How do I check NaN? -- Toytoy (talk) 12:34, 13 February 2011 (UTC)[reply]

You're looking for isNaN(number). --dapete 13:02, 13 February 2011 (UTC)[reply]

It is sort of wacky, but the IEEE standard for floating-point defines 'NaN' as a special floating-point value to be used when the result of an operation is not a defined number (5 divided by 0 results in NaN, for example). When types are used for performance reasons, it's really useful to know the type of the result an operation in advance (without knowing what the arguments are), so in that way, it's a useful convention that NaN is a floating-point value. Paul (Stansifer) 13:57, 13 February 2011 (UTC)[reply]

Special bonus trivia: You can generally test for x being NaN with x != x; the standard also defines that NaN is not equal to anything, including itself. This is, of course, kind of horrifying, if you expect equality to be an equivalence relation. Paul (Stansifer) 18:54, 13 February 2011 (UTC)[reply]

5/0=inf, not nan. 0/0=nan (but not ==, of course, as Stansifer said). --Tardis (talk) 15:00, 14 February 2011 (UTC)[reply]

Thank God I learned to do math before I am polluted by computer science conventions! Ha! -- Toytoy (talk) 11:54, 14 February 2011 (UTC)[reply]

Now I'm curious. What should typeof(parseFloat("!")) return, in your un-sullied opinion? --Tardis (talk) 16:02, 14 February 2011 (UTC)[reply]

Harumph! Computer scientists are perfectly happy to specify a solution that takes thirty times as long to do arithmetic, but does the right thing. The mathematical weirdness here is all caused by compromises made with software engineering constraints. You can blame all those annoying consumers who wanted to play Doom at more than 3 frames per second. Paul (Stansifer) 17:16, 15 February 2011 (UTC)[reply]

Vista - 'Read Only'

Hi everyone - I am trying to remove the 'Read Only' thingy from a folder (and subfolders there-in) which I have here on my computer. Right clicking 'Properties' and un-checking 'Read Only' seems to do the job well enough, until I right-click 'Properties' again straight afterwards only to find it is 'Read Only' again. No matter what I do, this 'Read Only' still persists. I have used Start Menu>Explorer.exe (Run as Admin) to no avail. I have tried with the folder in Program Files (where it was to start off with), in Documents, and on Desktop, all to no avail. Is there anything I can do to accomplish this? --KägeTorä - (影虎) (TALK) 12:58, 13 February 2011 (UTC)[reply]

I had this same problem under Windows 7 -- when trying to remove the read-only attribute from a folder in Program Files, Windows would tell me that something had happened, but the folder was still read-only. I believe you have to right-click on the folder, click Properties, then Security and give yourself "Full Control". I found this guide that outlines that process, but it seems to go more in-depth that is needed (actually giving you ownership of the folder, rather than just permission to modify the files). Xenon54 (talk) 17:02, 13 February 2011 (UTC)[reply]

Excellent! --KägeTorä - (影虎) (TALK) 00:17, 15 February 2011 (UTC)[reply]

In the the Properties of a folder, the Read-only checkbox is used to change the status of all the files in the folder, but doesn't show or change the read-only status of the folder itself. When you open the Properties of a folder, the Read-only checkbox always ~~shows a half-way gray state~~ contains a square (or a light gray checkmark). This means "don't make any changes to the read-only status of the files in this folder." You can then check or clear the box and click OK to change all the files in the folder to read-only or read-write.

The actual read-only bit of a folder is used by Windows for purposes other than restricting write access. If you really need to see or change it, you can use the attrib command, as described in the Microsoft support doucment below.

--Bavi H (talk) 19:43, 13 February 2011 (UTC)[reply]

'Half way gray state'? No idea what that means - full blue box on my machine. Anyway, cheers. --KägeTorä - (影虎) (TALK) 00:15, 15 February 2011 (UTC)[reply]

You're right. It's called a tri-state checkbox. In the default display style in modern Windows versions, the third state has a square in the box. When Windows XP is set to Windows Classic display style, the third state is a light gray checkmark, like this: tristate.gif. "Half way gray" was unclear so I revised it above. --Bavi H (talk) 02:32, 15 February 2011 (UTC)[reply]

Severe Bluescreen problem - I may have to format and reload Windows 7

I think I have got some viscious malware as I haven't installed any new software and I haven't attached any new hardware - but suddenly I am getting the bluescreen seconds after windows7 finishes loading. The bluescreen gives a variety of 'reasons'. Once it told me it had a problem with CDROM.SYS and once that I had a "system service" problem - that one also gave me an error code (0x80070002). Mostly it just tells me "IRQL not less or equal" then shuts down.

I have booted in safe mode and gone back to a known safe restore point but it still happens - weird!

I suspect that I may have to reinstall Windows (Yeuk!) but if I do I want to do the job REALLY thoroughly and run a low level format of my C drive first.

QUESTIONS: 1. How do I do a low level format prior to reinstalling? 2. Has anyone any bright ideas that may save me from the dreaded reinstall?

I am currently running on an old PC running Windows XP - I just LOVED XP.

Hoping you can help. Gurumaister (talk) 14:04, 13 February 2011 (UTC)[reply]

Before you do this, try the following.

Boot up in "Safe mode with Networking"
Go to http://www.malwarebytes.org/ and download the free version
Update it
Run it

This utility can clean up a lot of malware w/o having to redo your installation from scratch. Exxolon (talk) 16:25, 13 February 2011 (UTC)[reply]

Exxolon - that was excellent advice. thank you. I have loaded and run Malwarebytes and I seem to have a stable (so far) system. I am very grateful! Gurumaister (talk) 17:13, 13 February 2011 (UTC)[reply]

Svg vs GIF

Svg vs Gif which is better and why Rahul^{Text me} 17:28, 13 February 2011 (UTC)[reply]

SVG is good for drawings, cartoons, diagrams, etc, but not for photographic images. GIF is really an obsolete format for any purpose except animation. For photos, Jpeg is usually the best choice unless you need perfect precision, in which case PNG is usually the best choice. Looie496 (talk) 17:49, 13 February 2011 (UTC)[reply]

They fit different purposes. GIF is a relatively old format for raster graphics, whereas SVG is a format for vector graphics. In other words, an SVG file is a set of instructions on how to draw a picture at any size, whereas a GIF file is a picture of fixed size (in pixels).

For most purposes, GIF has been obsoleted by PNG and JPEG. GIF only supports 256 colors in one picture and single-bit transparency, whereas PNG and JPEG support millions of colors. But there's one thing GIF can do that PNG and JPEG can't: animation. GIF is widely used on the Web for small, compact animated images.

Wikipedia uses SVG extensively for things like logos, maps, and other drawn graphics which may need to be resized, or printed at different resolutions. This is because you can resize a vector image without losing image quality, whereas a raster image (like a GIF or PNG) loses information when shrunk and becomes "pixelated" when scaled-up. But SVG isn't useful for photos, since digital photos are raster data. --FOo (talk) 17:52, 13 February 2011 (UTC)[reply]

Actually PNG can do animation, see APNG 82.43.92.41 (talk) 18:06, 13 February 2011 (UTC)[reply]

APNG is an unofficial extension to PNG that was rejected by the PNG group. Using it on Web sites would be a bad idea since less than 50% of all Web users can view it: it's not supported by Internet Explorer, Safari, or Chrome; only by Firefox and Opera. --FOo (talk) 18:23, 13 February 2011 (UTC)[reply]

SVG can also be animated, though many browsers have limited support and poor performance. We should draw attention to the important distinction between "the file format specification makes a feature possible" and "most web users will be able to use that feature." For example, GIF transparency had poor support in early web browsers; PNG support was totally lacking until just a few years ago. While I would argue that PNG is the best and most portable graphic format for "general web graphics", it has only become feasible recently as web browsers adopted support for it. The same can be said of SVG today: the variance in rendered SVG graphics between current browsers can be very large, so a web designer should use SVG with caution (even if it's a "better" vector format.) Nimur (talk) 21:05, 13 February 2011 (UTC)[reply]

Laptop

I used to have a "laptop" computer very similar to this with the orange monochrome screen (which I bought for £1 somewhere since it was so old and not working properly). I still have it, thought it's broken now. I have several questions;

Was / is it worth anything to a collector?
What technology was the screen made of? What gave it that orange glow?
Is it possible to emulate the same kind of orange monochrome display on Windows 7 using a standard modern screen, just for fun?

82.43.92.41 (talk) 18:04, 13 February 2011 (UTC)[reply]

These are called "amber" monitors, ~~and our article Monochrome monitor discusses them and the amber glow~~; but I have never seen an amber monitor that displayed graphics like that; every monochrome monitor I have ever seen was hooked up to a IBM Monochrome Display Adapter or the like, which displayed text but was not capable of displaying graphics. (Side note, these adapters and monitors were coveted among programmers for a while in the 1990s after they had gone out of production, because it was a particularly easy way to output debug text and have a multiple monitor setup for doing so, at a time when this wasn't practical with 'normal' monitors.) Comet Tuttle (talk) 18:42, 13 February 2011 (UTC)[reply]

Comet Tuttle: I don't think you're right. I believe the monitor on that photo the OP linked to is an LCD monitor, so it has no relation to those amber monitors you mention. I suspect this because notebooks from that age usually came with LCD monitors, as CRT are too heavy and fragile, and also are thicker than would fit in that panel. I am puzzled on the amber color though, because the displays in the similar notebooks I've seen are plain white (or at least close to white).

As for your other question, I don't think the notebook would be valuable for collectors, but I can't be sure. – b_jonas 19:38, 13 February 2011 (UTC)[reply]

I agree, it's not a monochrome amber monitor. I have stricken the corresponding phrase above. Comet Tuttle (talk) 17:17, 14 February 2011 (UTC)[reply]

Thanks for the responses. The screen could absolutely display graphics; I remember drawing in paintbrush on Windows 3.11 with it. It also seemed to have two modes from what I remember - all orange with black lines and text (Windows 3.11) or all back with orange text (DOS mode) if that helps narrow it down 82.43.92.41 (talk) 20:14, 13 February 2011 (UTC)[reply]

I think it's a monochrome plasma display. -- BenRG (talk) 21:57, 13 February 2011 (UTC)[reply]

I agree with BenRG that the display is most likely a monochrome plasma display. Around 1990, high-end "portable" and compact computers used these displays because they were larger and had higher resolutions than what LCDs could provide at the time. LCD technology was pretty primitive back then compared to today, VGA resolution was not possible, for example, IIRC, and size was limited to under 10 inches. Since your "laptop" is similar to the Toshiba T3200SX, which was a business laptop featuring such a plasma display, and was marketed as being equivalent in most respects to a desktop business PC, its possible that a collector may be interested in it, even if its not usable (likely for spare parts - plasma displays are not exactly run-of-the-mill). Don't expect it to be worth lots of money, since computers depreciate pretty badly - folklore has it that a supercomputer site with a Cray that was bought for millions was worth a few thousand after it was decommissioned, and after failing to find someone to take it away, it was scrapped. In my experience, collectors are most interested in computers that are not run-of-the-mill, or if its something popular like an Amiga or Apple. Rilak (talk) 02:43, 14 February 2011 (UTC)[reply]

That brings back memories. I was using a Compaq Portable with plasma display to do AS/400 traces on twinax until a year ago. The Azure trace boards only worked in an ISA slot and no one made a similar product for any modern laptops. ---— Gadget850 (Ed) ^talk 16:44, 14 February 2011 (UTC)[reply]

Google Maps

I have an issue with this Google Map of Munich. Is there a way to directly notify Google that their maps are broken and can't tell me which road is which, or do I have to suffer through their help forums? Xenon54 (talk) 18:07, 13 February 2011 (UTC)[reply]

If you right-click on a Google map, there is a "report a problem" option at the bottom of the menu you get. This takes you to a small form that you can fill out with a description of the problem. I've used it in the past and gotten a reasonably prompt response -- make sure you give a clear and concise description of the problem and why it is important, though. Looie496 (talk) 18:37, 13 February 2011 (UTC)[reply]

The "Report a problem" link appears in certain countries -- Austria and Switzerland but not Germany (of course). I've tried doing it at the point where the A8 crosses the Austrian border, but I never even got the confirmation e-mail. Xenon54 (talk) 19:04, 13 February 2011 (UTC)[reply]

Strangely, I see no problems with the map provided by the OP. The large streets are labelled, the smaller streets are only labelled when you zoom in. The same goes for route numbering, though may city streets have no route number. Astronaut (talk) 03:04, 14 February 2011 (UTC)[reply]

If the problem is Google's rendering of the data, you'd need to go through Google's forums. If the underlying data is wrong (e.g. if roads are misidentified, or shown with incorrect connections) then that report would need to go to the supplier of the data. That's what the "report a problem" link does, but only for suppliers that Google knows how to communicate errors to; some don't. In this case it seems the map is supplied by TeleAtlas - they have their own report-a-problem app here. Note incidentally that Bing Maps for the same city uses map data from NAVTEQ instead, and so in addition to using Microsoft's rasteriser rather than Google's, it's different underlying data, and may suit your purposes better. If you've noticed just a very small imperfection, it could be a trap street; Open Street Map lists a large number of such features in TeleAtlas' database here. Finlay McWalter ☻ Talk 14:15, 14 February 2011 (UTC)[reply]

Forms on MS Word

Hi, I'm trying to make a form on MS Word and even found some characters that look like squares to use as checkboxes when I print them out. (Here it is: □) But they're too small. How do I make them bigger without messing up the line spacing? I tried putting 1.5 and even double spacing, but it keeps messing up the lines whenever I try to make them more than size 10pt. Thanks! --Jeevies (talk) 20:37, 13 February 2011 (UTC)[reply]

You could use a drawn square that you treat like an ordinary textual character (I don't know the English term for this. In Swedish it's called "I nivå med text".) --Andreas Rejbrand (talk) 20:57, 13 February 2011 (UTC)[reply]

I tried this first. Unfortunately, these are even more effective for creating imbalance between the line spacing. Also, when using the "in line with text setting" the box stays fixed upon the line of text when I need it to move slightly lower. The "tight" and the "square" settings create too much space in the sides when I want the box to be close to the word "yes" or the word "no". Thanks for replying quickly though! --Jeevies (talk) 21:24, 13 February 2011 (UTC)[reply]

I use empty text boxes for this type of application. It's not what they are intended to be used for, but small text boxes can be adjusted to any position and do not affect the flow of text when appropriately formatted. Once you've got one formatted, just copy it to save time (hold "ctrl" & drag), and hold the alt key to allow fine adjustment. One disadvantage is that (maybe just older?) versions of Word can get confused if you have too many such boxes on a page. I see many badly-designed forms using other techniques. Dbfirs 07:59, 14 February 2011 (UTC)[reply]

You could use [‾] - it's a left square bracket followed by an underlined overline followed by a right square bracket. Probably not the most technical solution, but it looks like a box to me. Rocketshiporion ♫ 23:29, 15 February 2011 (UTC)[reply]

Editing a .docx (MS Word) document that has fields

I was given a Word document that I need to fill out, it has text input fields (the gray boxes you type in) but there are also some parts I need to edit directly that are not in fields. But I can't click on, or select, or in any way edit, the stuff not in the fields—it seems that documents with fields only let you edit the fields, not the other text. Does anyone know how to disable the fields in such documents, or enable editing the rest of the document, or just open the document in some way that allows normal editing? rʨanaɢ (talk) 23:45, 13 February 2011 (UTC)[reply]

You may be able to disable it by going to Tools -> Unprotect Document in Word. It may ask you for a password, and if you don't know that, you're going to have to guess. Or if you're really willing to think outside the box, you could contact the person/organization who generated the form. --Colapeninsula (talk) 11:14, 14 February 2011 (UTC)[reply]

Ah, found it, thanks. rʨanaɢ (talk) 15:35, 14 February 2011 (UTC)[reply]

No need to guess, from memory of last time I searched it's trivial to break Word read-only document protections (if the file is encrypted and you need a password to open and you don't have that password then obviously you're SOL). This isn't surprising, in the absence of a hardware protection layer that the content never leaves it should be expected, even more advanced protections like those for Bluray are usually broken to some extent (and there's always the analog hole). Of course doing so may violate the DMCA or any similar local laws although I'm not convinced guessing the password would be any better. Nil Einne (talk) 08:37, 16 February 2011 (UTC)[reply]

February 14

Two questions:

1. Is the Asus U81A-RX05 still on the market, and NOT as a secondhand?

2. My computer says it can't detect an operating system, when there was one. But I don't have an OS CD, so how do I rectify this situation? 24.189.87.160 (talk) 06:51, 14 February 2011 (UTC)[reply]

1: A quick googling suggests "no", but that's at the big stores that show up first in Google searches. It might be available on the shelf at some smaller computer stores that haven't sold through their inventory. #2: What OS? My first suspicion is that there has been damage to, or erasure of, the first few sectors on your hard disk. Personally I would go and buy an external USB hard disk to be a backup device, then I would use a friend's computer to download the Ubuntu boot CD and burn a copy, then back at the damaged computer I'd boot the Ubuntu CD and see if it can detect your hard disk. If so, back up everything you care about to that external USB hard disk. Then it's time to borrow a boot disc from a friend (make sure it is the same OS version you used to have) and boot the damaged computer from that disc, and choose the "Repair" option, if available. Comet Tuttle (talk) 17:15, 14 February 2011 (UTC)[reply]

My computer is running Windows XP, and to be honest I can't find anyone with a back up Windows XP OS recovery disc, nor do they sell them. So am I screwed here? 24.189.87.160 (talk) 06:55, 15 February 2011 (UTC)[reply]

I wouldn't say you're screwed. One option you have is to buy a new hard disk and install a newer version of Windows on it, and hook up your old hard disk as a second drive. If your system is a desktop PC then this is pretty easy; if it's a laptop PC then you'll probably have to buy a USB hard disk enclosure for the old drive. Boot up the PC with the new version of Windows and see if it can read the old hard disk's contents. Then copy all the files you can from the old hard disk to the new hard disk. And let us know what happens. Comet Tuttle (talk) 21:20, 17 February 2011 (UTC)[reply]

windows

Can I install 32 bit windows 7 on 64 bit hardware? —Preceding unsigned comment added by 85.179.147.59 (talk) 10:57, 14 February 2011 (UTC)[reply]

Check This It will solve your all problems Rahul^{Text me} 13:31, 14 February 2011 (UTC)[reply]

I'd like to know the answer to my question before I buy any computers. The software you link to requires one to already be in possession of a computer. 85.179.147.59 (talk) 13:49, 14 February 2011 (UTC)[reply]

You can install a 32 bit OS on a 64 bit system. The limitation is that you will be running a 32 bit OS. You will not able to run 64 bit applications on the 32 bit OS. -- kainaw ™ 13:50, 14 February 2011 (UTC)[reply]

Thanks 85.179.147.59 (talk) 13:59, 14 February 2011 (UTC)[reply]

In the specific case of Windows (although also with many other OSes you'll get a similar issue) you're liable to be limited to about 3GB, any more RAM will go unused. Nil Einne (talk) 15:46, 14 February 2011 (UTC)[reply]

This question made me wonder if a 16bit OS like DOS could run on 64bit hardware. I know you can't run 16bit programs on 64bit Windows because it only emulates a layer for 32bit programs, but could DOS work directly on the 64bit hardware? 82.43.92.41 (talk) 19:11, 14 February 2011 (UTC)[reply]

You can install something like qemu to emulate a 16-bit processor and install a 16-bit OS, but you won't be able to natively run a 16-bit OS on a 64-bit processor. Depending on the model, the 64-bit processor either has 32-bit hardware or a 32-bit emulator inside the 64-bit processor. It will not have 16-bit functionality. I suggest qemu because it emulates known "features" of some of the older chips that are needed to get old programs that used very bad programming practices to run. -- kainaw ™ 20:12, 14 February 2011 (UTC)[reply]

Actually 64-bit processors (to be precise: x86-64 compatible ones) behave just like an old x86 processor ("legacy mode") until they are switched to long mode, which is needed to run 64-bit code. In legacy mode it should be able to run any old 16-bit code, and even in long mode it is (as I just learned from the article) still possible to run 16-bit code in protected mode. See also this table. --Tokikake (talk) 10:42, 15 February 2011 (UTC)[reply]

I had seen an attempt to install DOS6.2 on an AMD64. It failed. I will try it to see if it is truly the processor or something else that caused it to fail. -- kainaw ™ 13:30, 15 February 2011 (UTC)[reply]

I don't know about the DOS 6.2 issue although I'm pretty sure I've run some version of 16 bit DOS on a AMD64 comp before for bios updates and the like (while there are a few 32 bit DOS and lots of DOS extenders, most are 16 bit AFAIK) and this possibly includes DOS 6.2 boot disks of some type (I've had an AMD64 comp since 2005). Also I'm currently running a rather old AMD64 computer with XP x32 (running natively) and Alley Cat (video game) and other 16 bit apps run fine (well as fine as they do on XP and the WoW or NTVDM DOS layers). Of course, they don't work on XP x64 or other 64 bit Windows versions without an emulator. Nil Einne (talk) 08:32, 16 February 2011 (UTC)[reply]

I tried it at home last night. Swapped out my drives in my computer. Put in an old IDE drive. Downloaded an old 16-bit DOS. Made the floppies (which required digging in the closet for an old floppy drive). The result - no go. It doesn't appear to be a CPU problem. It appears to be that DOS doesn't support the other hardware like the AGP video card. It starts to install and then there is no video. The USB keyboard/mouse stop responding (pressing caps-lock does nothing). I have to hard-reset. -- kainaw ™ 13:21, 16 February 2011 (UTC)[reply]

Clear Screen C++

I am messing around with a MUD (Rom v2.4b6 is the codebase) and I am running into a problem trying to clear the in-game screen of text. I am using Cygwin for windows to compile. Here is what I am trying to do.. You log into to the text game and a new user types in their character name, and they choose a password. At that point their character is created and they go on to choose a sex, race, class and other things. This is how it looks:

Enter a name: Joeblow

Welcome, New user.

Choose a password: *****

Reenter password: *****

Welcome to the game!

Please choose a sex (M/F):

What I want to happen is after it says Welcome to the game I want a whole new blank screen to appear to continue the character creation process (at the top of the new screen would be Please choose a sex (M/F), instead of continuing on the same screen as above). I have tried:

printf ("\033[2J");

And that doesn't work. I even tried enabling ANSI.SYS but nothing changed. I also tried system calls "cls" and "clear" but all that did was clear the screen on my cygwin terminal window, not inside the actual game.

If there is anyone out there that can help me with this, I would be greatly appreciative. Sorry for being so overdetailed but I am just trying to get the idea out there of what I am trying to do. I've seen other MUDs accomplish this so I know it is possible. Thank you! —Preceding unsigned comment added by 70.129.41.230 (talk) 15:03, 14 February 2011 (UTC)[reply]

I do not understand what you mean by "inside the actual game". The only aspect of being in the game is that the user knows is the terminal. So, if the terminal screen is cleared, the game screen is cleared. By understanding what you mean better, it may be possible to come up with a suggestion. -- kainaw ™ 15:44, 14 February 2011 (UTC)[reply]

I don't understand what you mean about game vs. console, but wouldn't an old-fashioned:

for (int i = 0; i < num_screen_lines; ++i)
    puts("");

do the trick if nothing else will? --Sean 15:54, 14 February 2011 (UTC)[reply]

How are you connecting to (not starting) the game? You distinguish your terminal window from the game, so it must be a network connection (as it should be). If you're just using telnet, it may not support the ANSI codes. --Tardis (talk) 16:25, 14 February 2011 (UTC)[reply]

You might want to use a terminal library like ncurses. ncurses can give you programmatic access to more complicated terminal behaviors, including clearing the entire visible screen, editing characters on previous lines, and so on. If you are strictly using the C or C++ standard I/O library, you only have the capability to print characters, so you'll have to "clear the screen" by printing a lot of blank lines. Nimur (talk) 18:04, 14 February 2011 (UTC)[reply]

I'm totally unfamiliar with the ROM (MUD) system, but based on general programming experience it is very likely to contain a set of functions for managing the display, and you will need to use one of those functions to clear the display, or bad things will happen. If the system works like every other I have seen, it maintains an internal memory of what the display shows, and if you try to clear the display using some external means, you will probably leave the internal memory in an inconsistent state. Looie496 (talk) 18:10, 14 February 2011 (UTC)[reply]

Thank you for your responses and trying to help with my issue. Fortunately someone on another forum provided me a line of code that cleared the screen and it works perfectly in most telnet apps (it doesn't work in MUSHClient and GMud as they don't allow clear screen). Here is the code just in case this could help anyone else in the future:

write_to_buffer( d, "\x1b[2J\x1b[H", 0 );

Again thanks for trying to help. ANSI codes are a weird and mysterious thing.—Preceding unsigned comment added by 70.129.41.230 (talk) 00:31, 16 February 2011 (UTC)[reply]

rm -rf / on Linux

Does the Linux rm command recognize / as being special, or does

sudo rm -rf /

actually remove the entire file system? -- Bk314159 (Talk to me and find out what I've done) 17:40, 14 February 2011 (UTC)[reply]

It will attempt to unlink the entire filesystem, but will most likely fail before completing the task. I used "unlink" because it removes the references to all files, but does not remove any of the files. Often, a system may be restored when only references have been removed, but it is very painful to do so. -- kainaw ™ 17:55, 14 February 2011 (UTC)[reply]

For example, attempting to rm the device files in /dev/ will fail in most Linux and Unix systems, regardless of your user rights. Other filesystems and mount points may also fail to unlink, unmount, or delete, depending on your flavor of *nix. Nimur (talk) 18:01, 14 February 2011 (UTC)[reply]

See rm but also a bug about it: the behavior may not be consistent. --Tardis (talk) 18:28, 14 February 2011 (UTC)[reply]

root directory ¦ Reisio (talk) 18:50, 14 February 2011 (UTC)[reply]

Unix provides the superuser with nearly endless possibilities, this includes the possibility to shoot yourself in the foot. There's a reason why sudo displays a warning when you run it the first time, see Sudo#Design. -- 78.43.71.225 (talk) 20:01, 14 February 2011 (UTC)[reply]

Because Ubuntu completely misses the point of sudo. :p ¦ Reisio (talk) 20:31, 14 February 2011 (UTC)[reply]

I'm rather sure I saw sudo's warning message on Linux long before Ubuntu even existed. Now get off my lawn! ;-)-- 78.43.71.225 (talk) 22:50, 16 February 2011 (UTC)[reply]

No doubt after it was properly configured. ¦ Reisio (talk) 13:45, 17 February 2011 (UTC)[reply]

Even the task manager wouldn't come up on Firefox

At a library with Mozilla Firefox and Windows XP, the computer completley froze for about ten mintues shortly after being turned on. One time I was told this was due to the virus updates. On one occasion when I knew no one could help me except with CTRL-ALT-DEL, I decided to try that just to see what would happen. The list of options, including task manager came up, and I chose "task manager". I saw a list of what was going on, and I don't remember what I did, but everything unfroze. Yesterday, however, the task manager wouldn't even come up. I got the list of options but when I clicked on "Task manager", nothing happened for the longest time, and I couldn't get anything to work. Eventually, though, the computer unfroze. It must be pretty bad if even the task manager won't come up.Vchimpanzee · talk · contributions · 19:16, 14 February 2011 (UTC)[reply]

Is there a question here? The Reference Desk isn't your blog. 94.222.206.176 (talk) 19:37, 14 February 2011 (UTC)[reply]

Yes. Why would the Task Manager not come up?Vchimpanzee · talk · contributions · 22:04, 14 February 2011 (UTC)[reply]

Because it took a very long time to load? This seems rather obvious from your description. If the computer is still using Windows XP there's a good chance it's still a single core with very little RAM which undoutedly doesn't help Nil Einne (talk) 22:58, 14 February 2011 (UTC)[reply]

There are any number of conditions that can cause a computer to lock up so that the Task Manager is no longer available. One example might be if the CPU overheats. StuRat (talk) 08:14, 15 February 2011 (UTC)[reply]

Nil Einne, I'll ask someone if this is the case. StuRat, the black box was making a lot of noise but it had just been turned on. There are some numbers on it, since I'm here. HP Compaq with a Celeron. Without my bifocals, I'd better not attempt these numbers. It says Windows XP Home Edition. That's strange. This is a library. The problem is relatively rare. One idea I came up with is the next time this happens if the Task Manager comes up I could write down those letters and numbers that come up on the screen. I didn't think of that when it happened.Vchimpanzee · talk · contributions · 15:36, 16 February 2011 (UTC)[reply]

I posted what I believed were the numbers for this computer, or thought I did. Maybe I clicked on "Show preview" and never got past it. Anyway, I have my bifocals on and I am absolutely certain the computer is a hp Compaq 220 MT, which is what I attempted to post yesterday.It also has Windows XP Home Edition, which is strange since this is a library. Obviously the updating done for the software wouldn't be printed on it, but M3C38-GTY2V-73WGM-FVPGM-4RR4Y mean something.Vchimpanzee · talk · contributions · 23:22, 17 February 2011 (UTC)[reply]

GPL and other Open Source licenses

What's the point of forbidding closed source forks of open source projects if, by definition, closed source projects are those whose source code is kept secret and, therefore and in theory, one can't prove that GPL'd source code has been used? --Belchman (talk) 19:50, 14 February 2011 (UTC)[reply]

Just because they may be keeping the source code secret doesn't mean it's impossible to figure it out. [3] Reach Out to the Truth 19:59, 14 February 2011 (UTC)[reply]

More examples: List of software license violations ¦ Reisio (talk) 20:41, 14 February 2011 (UTC)[reply]

Indeed. The Software Freedom Law Center [4] and other organisations have been extremely successful in enforcing the GPL so far. In general, if you can demonstrate reasonable suspicion, any court will ensure that the source code is made available for the purpose of the lawsuit, so that the copyright status can be determined. For the US situation, see Discovery (law). --Stephan Schulz (talk) 20:24, 14 February 2011 (UTC)[reply]

The Gnu General Public License explicitly forbids "forking" to a different license if the original software is derived from software licensed under the GPL.

If you have GPL-licensed software and source-code that you want to limit distribution, a more strategic approach might be to release the software under the GPL, and enter into a mutually consented business contract not to redistribute the software or source-code. (Just because your license legally permits the customer to redistribute the program doesn't mean they must redistribute it - especially if they have no economic incentive to share the program they just paid for). And if the customer doesn't redistribute the program, they don't need to redistribute the source-code either. There's actually a good case for using GPL'ed software to legally protect commercial free-software from price deflation. The GPL license protects the software author's rights to redistribute or resell their creation, while simultaneously giving the software users the right to modify it. This can help keep the sale-price of the software non-free, while preserving the freedom to examine and modify the source-code. See the article Gratis versus Libre Also, have a look at the Official GNU policy on Selling Free Software - they "encourage people who redistribute free software to charge as much as they wish or can."

Of course, a party may violate the terms of any license agreement, whether it is GPL or any other license, in contravention of license agreements, contractual obligations, and local laws - and incurs any legal liability for doing so. This only really matters if some legal entity pursues the license violator - which is often prohibitively expensive for creators of free software. Nimur (talk) 21:01, 14 February 2011 (UTC)[reply]

A company that tries to develop closed code from a GPL'ed code base is going to be highly susceptible to blackmail, explicit or implicit, from its own programmers. It wouldn't be a very intelligent approach. Looie496 (talk) 23:20, 14 February 2011 (UTC)[reply]

Thanks. --Belchman (talk) 00:25, 15 February 2011 (UTC)[reply]

iNAC managed access blocking of prison phone calls - how does it work, and is it the same as the suppression of cell phones at political protests?

I read about a California trial of "managed access" to block calls from smuggled cell phones in prisons. While it sounds like a straightforward idea, I am wondering how general this control is, and whether adoption of the system will make it even easier for governments or others to block or intercept people's calls.

The system "routes mobile calls originating in the prison to a third-party provider that check's each number to see if it's on a whitelist; if it doesn't make the cut, the call is blocked.^[5]

Now even in the early 90s I remember that one feature of major political protests in the U.S. is that every cell phone in the area goes dead. I've since seen similar reports from half a dozen other countries - it sounds like it's always a surprise to people when it happens, even after all these years. I'd always just assumed that someone gave a call to have a local cell tower shut off or something, but after reading about this system, I wonder if they've been using the "managed access" approach all this time. If I understand correctly, it implies that there might be some sort of recognizable truck in the police response to a major protest, which carries the "third party provider's" mini cell phone tower. It also suggests, for example, that the identity of every cell phone in the crowd at any such demonstration is automatically logged as a part of this process.

Can anyone shed more light on how this process works? Does widespread adoption imply any change in how cell phones work for the general public? What are the most relevant articles? Should a stub article be started at iNAC managed access or is there some better name? Wnt (talk) 21:19, 14 February 2011 (UTC)[reply]

The "managed access" you describe sounds like a microcell or picocell attached to a specialized phone network. A phone locks onto the strongest signal available for its network, so if the strongest signal is from such a device, your phone wouldn't see any further-away free-world access points.

This is distinct from just shutting off cells in an area. I have no idea of when or whether this is done for protests in the US, though it would not surprise me -- telecoms companies are heavily regulated, and government is very much in a position to demand such a thing. But keep in mind that cells also support a limited number of calls, and in crisis situations (most famously 9/11) they can easily becomes saturated. --FOo (talk) 08:26, 16 February 2011 (UTC)[reply]

Thanks! I doubt it was overload - I saw it happen in a rather sparse crowd, where larger events routinely occur in Chicago. But your article led me to use "cellular base station" as a search term, with which I found reference to "Triggerfish" (we have no article on Wikipedia about anything but the fish), also known as "cell-site simulators" or "digital analyzers". [6][7][8][9][10] All of the references I've read focus on the uses of the system for surveillance, evading what small legal requirements may exist for obtaining phone information; but clearly if this technology works as you describe, it is capable of generally denying cell phone coverage to a defined area, even by 'accident'. Wnt (talk) 04:57, 17 February 2011 (UTC)[reply]

Based on the information I found, I started the article Triggerfish (surveillance). Feedback and assistance would be most welcome. Wnt (talk) 07:59, 17 February 2011 (UTC)[reply]

iPhone 3GS with an old bootrom

Does the iPhone 3GS model that has the old bootrom check SHSH blobs (i.e., is there any hardware based authentication)? --Melab±1 ☎ 22:07, 14 February 2011 (UTC)[reply]

The Art of computer programming

I am confused by The Art of Computer Programming by Donald Knuth. Obviously Vols 1-3 are published and available. Is/Will Vol 4 be one big book or 3 books (4A, 4B, 4C)? What is available NOW, what will be available later this year? What is a Fascicle? Do Fascicles 0 to 5 equal Vol 4A? Will DK live long enough to finish Vols 5,6 and 7 - especially if Vol 5 isn't out til 2020?

My main reason for asking is that I don't want to buy things twice and I would prefer to buy the books when they are as big/collected as they'll ever be. In my simplistic world that would be 7 books. But if Vol 4 will always be 3 books then 9 books. I think the Fascicles are things I don't want.

Guidance appreciated - the WP: article wasn't clear enough. Thanks. -- SGBailey (talk) 22:42, 14 February 2011 (UTC)[reply]

Professor Knuth has been "preparing" the 7th volume since... about 1981. I don't think it's available in its entirety and it is doubtful if it ever will be. The authoritative place to check is Professor Knuth's "recent news" page, and the official Art of Computer Programming website. "Fascicles" are sort of like a few related chapters released as an "addendum" unit; so far, a few have been officially distributed to the publishing houses, and a few others are available "locally." With due respect, the wording on his webpage is a bit fatalistic, the expected completion date is listed as 2020, and I doubt he will ever "complete" the book. Nimur (talk) 22:52, 14 February 2011 (UTC)[reply]

voice

how do i use a voice changer with skype — Preceding unsigned comment added by Tomjohnson357 (talk • contribs) 22:54, 14 February 2011 (UTC)[reply]

What is happening? General Rommel (talk) 07:59, 15 February 2011 (UTC)[reply]

February 15

Maximum Length of Petaflop-Year Crackable AES-128 Password

Resolved

What is the maximum possible length of a AES-128 password used to encrypt text of length 1024 bytes, which can be brute-force decrypted with one petaflop of computing power in one year? In other words, how short does an AES-128 password have to be to be cracked with one petaflop of computing power in one year? This is not a homework question. Rocketshiporion ♫ 00:18, 15 February 2011 (UTC)[reply]

As I said before, AES doesn't define any way of encrypting a file with a password. Everyone has a different way of doing it. Supposing that your chosen encryption format's key derivation function takes a typical modern computer 0.1 second to compute, and your petaflop cluster is, I dunno, 100,000 times faster than that, then it can test 1,000,000 passwords per second, or 2⁴⁵ per year. So the answer is a password with about 45 bits of entropy. This page will give you examples of random-character passwords with varying amounts of entropy. Note that the answer is independent of whether you're using AES-128, AES-256, Salsa20, or what-have-you to actually encrypt the plaintext. It depends only on the key derivation time, which varies over many orders of magnitude in real-world encryption software. -- BenRG (talk) 10:39, 15 February 2011 (UTC)[reply]

Just to clarify, by 45 bits of entropy, do you mean a password with 45 random characters? Rocketshiporion ♫ 23:18, 15 February 2011 (UTC)[reply]

No, shorter than that. It means, more or less, that you picked the password at random from a set of 2⁴⁵ possible passwords. For example, a password of 10 random uppercase letters would have about 47 bits of entropy because 26¹⁰ ≈ 2⁴⁷. The page I linked calls it "strength" instead of "entropy", and it could also be called "randomness". It's not really a well defined concept because it's often not clear what the set is that you're selecting from or what it means to select uniformly from that set, but it's the best answer that can be given to your original question. -- BenRG (talk) 07:02, 16 February 2011 (UTC)[reply]

Ah! That answers my question perfectly. Thank you! Rocketshiporion ♫ 05:06, 18 February 2011 (UTC)[reply]

Replacing a processor

Hiya WP! I'm planning to replace my belowed computer's processor in the near future. The current one is an adequate Celeron. What should I bear in mind when choosing a new one? 212.68.15.66 (talk) 10:28, 15 February 2011 (UTC)[reply]

Make sure your motherboard model supports the new processor. If it's a celeron, it may be somewhat difficult to come by a processor that will work with the motherboard. In my experience, after a few years replacing the processor means replacing the Motherboard, CPU, and RAM at the same time. You might get lucky though and the motherboard could support a Core 2 Duo! 206.131.39.6 (talk) 17:36, 15 February 2011 (UTC)[reply]

This could be the start of an eternal upgrade similar to what I do. I first upgraded my motherboard to the best motherboard that supported all my old hardware. Then, the next year, I upgraded by processor. The next year, I upgraded my RAM. The next year, I upgraded my CD player to a CD burner. The next year, I upgraded my video card to a fancy dual-head card. The next year, I replaced my CRT with two LCD monitors. The next year (due to power issues) I upgraded my 250W power supply to a 500W power supply. Then, I upgraded the motherboard again and started a whole new cycle. Last year, I upgraded my old IDE harddrive with two SATAs that mirror each other. I figure I'll keep upgrading one thing every year instead of purchasing a new computer. -- kainaw ™ 17:47, 15 February 2011 (UTC)[reply]

CPU speed improvements in the past few years have not been spectacular. Fortunately, for most applications, CPU speeds are already so incredibly fast as to be irrelevant. There are a few cases where CPU speed matters (scientific simulations, raytracing, databases), but most computing is RAM-limited. If the computer is paging at all, it'll probably benefit more from a modest RAM upgrade than any amount of CPU. Even if it isn't paging, it's worthwhile to have extra RAM to use as hard drive cache. As a bonus, RAM is usually easier to upgrade than a CPU. Paul (Stansifer) 18:15, 15 February 2011 (UTC)[reply]

If you're upgrading your computer, RAM is your best friend. I have 144GB of regular RAM in my computer, and everything runs incredibly fast because my computer doesn't use a pagefile. If you have to use a pagefile, either put the pagefile on a PCIe SSD or (if you're cost-concious) use a SATA III SSD as your boot drive, and put the page file on that. If your motherboard supports Core 2 processors, consider getting a Core 2 Quad instead of a Core 2 Duo. The extra threads permit more applications to simultaneously run faster on your computer. Rocketshiporion ♫ 00:01, 16 February 2011 (UTC)[reply]

Vector in C++ and maths

In C++, a vector is a one-dimensional array. I was wondering about the origin of the name, as it seems to have nothing to do with the vectors in mathematics. Anyone know? 212.68.15.66 (talk) 11:10, 15 February 2011 (UTC)[reply]

A mathematical vector is often represented as a column of numbers (similar to a matrix with a single column). This seems close to the idea of a one-dimensional array in computer science. Certainly, a C++ vector can be used to represent a mathematical vector (a direction vector of dimensionality N can be represented by a vector of length N), and the term vector processor seems to reference both meanings (it can be used for adding mathematical vectors, and acts on CS vectors). However vector does have many meanings in both math and computer science. --Colapeninsula (talk) 11:43, 15 February 2011 (UTC)[reply]

You, sir, are awesome. Thanks! 212.68.15.66 (talk) 12:02, 15 February 2011 (UTC)[reply]

Slow ADO Query over Access with VB6 over a LAN

My program uses MS Access as DB and Visual Basic 6. I've experienced an issue loading a recordset with about 300000 records, some fields indexed, when I place a SELECT SELECT * from Materials m INNER JOIN Quantity s ON m.code=s.materialcode ORDER BY code

in a ADO recordset with the following configurations:

Provider: Jet;OLEDB CursorType: adOpenForwardOnly LockType: adLockReadOnly CursorLocation: adUseClient

- - I place the query and pass to a datagrid, I've not to edit or modify the records ***

Strangely, if I use on the same machine where I've the .mdb file is fast, from other clients is slow (approx. 15 seconds).

What Can I change? Thanks. — Preceding unsigned comment added by Frankge973 (talk • contribs) 13:28, 15 February 2011 (UTC)[reply]

sound from heal

Can radar and wi-fi or hand-phone line or sate lit can receipt Frequencies from health and send it to every human ear?Example:me want to say halo to some person... me not use mouth to talk just use energy inside body and make some frequencies come out from the heal than use hardware radar and wi-fi or hand phone line or sate lit detect that frequencies come out inside body than lead into computer and use software filter the frequency than use computer send and connect to the radio station and sate lit lead the frequency into some person ears than the person will no need any electronics and this person also can receipt my sound halo from sate lit frequency..... — Preceding unsigned comment added by Jackfengyi (talk • contribs) 16:11, 15 February 2011 (UTC)[reply]

See Stephen Hawking. He uses a slight wiggle to send a signal to a device which converts it to input to a computer which manages the signals to put together text which is then converted into sound waves which are converted into electric signals that are sent to speakers which vibrate air which allows others to hear him say "Hello." -- kainaw ™ 17:43, 15 February 2011 (UTC)[reply]

You might also be interested in subvocal recognition, though I don't think any of that technology has made it beyond the lab yet. the wub "?!" 18:53, 15 February 2011 (UTC)[reply]

The OP's use of English makes it very difficult for me to understand the question. However, I think he is asking if some kind of electronically augmented telepathy would be possible. If so, he might find the work of Kevin Warwick interesting. Dr. Warwick's work has involved the implantation of electrodes in his brain. The electrodes were connected to the internet and allowed him to control a robotic hand from thousands of km away - if I remember correctly, the documentary I saw a couple of years ago featured this experiment where the robotic hand was in a lab somewhere in the USA, while Dr. Warwick controlled it from his office in the UK. Astronaut (talk) 23:42, 15 February 2011 (UTC)[reply]

NEW MOTHERBOARD

I want to buy a new motherboard. I have a 3.2 Intel processor and wanted to know if it'll be compatible with the new motherboard. It's an; Intel - Classic Series "Trinity Valley" G41 Motherboard. The features of the motherboard are:

The Intel Desktop Board DG41TY with microATX form factor offers legacy to premium features.
Parallel port, integrated VGA & DVI ports, Intel HD Video experience, Intel High Definition Audio and integrated 10/100/1000 network connection, enrich your multimedia creation experience.
The Intel Desktop Board DG41TY supports Intel Core2 Quad processors and Intel Core2 Duo processors and is Microsoft Windows Vista Premium WHQL certified.

Intel - Classic Series ""Trinity Valley"" G41

Socket LGA775 @ FSB1333 - For Celeron, Pentium Series & Core 2 Series CPU's
2x DDR2-800 (Dual)
4x SATAII, 1x ATA100.
1x PCI Express x16
1x PCI Express x1
2x PCI Slots
8x USB 2.0 (6x Cable)
Intel GMA X4500 VGA
Integrated Intel 6ch HD Audio Codec
Integrated Gigabit LAN
MicroATX —Preceding unsigned comment added by 41.215.117.157 (talk) 19:50, 15 February 2011 (UTC)[reply]

The two things that really matter are the socket on the motherboard and the type of processor you have. Unfortunately "3.2" (presumably meaning 3.2 GHz) doesn't identify the processor, so the question can't be answered at this point. Looie496 (talk) 20:50, 15 February 2011 (UTC)[reply]

Welcome to the Wikipedia RefDesk. Please try not to type in ALL CAPS. It's the online equivalent of screaming. Thanks. Rocketshiporion ♫ 00:05, 16 February 2011 (UTC)[reply]

Get silverlight

I have updated Silverlight but the get silverlight website still says that I have an old version! I have checked with the silverlight about and the add/remove and it says that I have 4.06, the latest version! See http://img717.imageshack.us/f/silverlight.png/ --Tyw7 (☎ Contact me! • Contributions) Changing the world one edit at a time! 20:41, 15 February 2011 (UTC)[reply]

Have you closed all browsers and restarted? Have you tried rebooting? Nimur (talk) 23:24, 15 February 2011 (UTC)[reply]

I even tried down right reinstalling. Uninstall, reboot and visit site Sliverlight not detectected. Installed silverlight reboot, old version detected. When I visit another site to check silverlight version, that site shows the correct silverlight version I have installed. When I tried to run the downloader and install it it says same version detected. Can you try it on your pc with ie8 and post me the screenshot. Emailed Microsoft, waiting for response --Tyw7 (☎ Contact me! • Contributions) Changing the world one edit at a time! 01:14, 16 February 2011 (UTC)[reply]

When pdf files fail

I have opened a pdf file with Acrobat Reader and Document Viewer, both in Ubuntu. The Acrobat view looks 'strange' and I'm sure that it was not what the author intended, with its cluttered font. The Document Viewer view, on the other side, has a normal font, which looks like Times New Roman. I thought that pdf files looked always right (that was the idea, I thought), but somehow this one do not has the fonts at hand. How can I discover which fonts are missing and solve this problem? Quest09 (talk) 20:43, 15 February 2011 (UTC)[reply]

evince (which is probably what you mean by Document Viewer) has a "properties" option in its File menu, which has a fonts tab. This lists fully and partially embedded fonts, and should list fonts that it gets from the system. Okular has the same thing. Searching around suggests the same feature is available in Adobe Reader at "File -> Document Properties -> Fonts". I don't have a PDF with non-embedded fonts to see exactly how it behaves in that case. -- Finlay McWalter ☻ Talk 21:48, 15 February 2011 (UTC)[reply]

Yes, I meant evince. And, yes, the problem seems that the author didn't embedded the fonts into the doc. I suppose, however, that both tried to guess a font, but evince had a better pick. Quest09 (talk) 22:49, 15 February 2011 (UTC)[reply]

I'd be interested to see a PDF with such an external font reference. If it's publicly available, could you link to it? -- Finlay McWalter ☻ Talk 22:52, 15 February 2011 (UTC)[reply]

Sure. Take a look at: [11] <1 MB. Quest09 (talk) 01:30, 16 February 2011 (UTC)[reply]

Yes, you're right. The fonts it needs are in the Microsoft Core Fonts distribution, so you might try installing that. -- Finlay McWalter ☻ Talk 11:20, 16 February 2011 (UTC)[reply]

I tried viewing the PDF with Foxit and it looks OK :/ You might want to try foxit as it is smaller and lighter --Tyw7 (☎ Contact me! • Contributions) Changing the world one edit at a time! 15:33, 16 February 2011 (UTC)[reply]

The problem here is not the viewer in question, it is the font available in Windows that is not available in Linux. Quest09 (talk) 17:47, 16 February 2011 (UTC)[reply]

No such font. ¦ Reisio (talk) 13:47, 17 February 2011 (UTC)[reply]

I don't know how it happened, but I just opened the document (Evince, Fedora 13, standard fonts, never added anything) and it looks just fine (see here, I included the fonts dialogue box from Evince for you). The font picked by the application seems to be Liberation Sans (~Arial). Normally the application should try to replace any font it doesn't know with anything it has at its disposal locally. --Ouro (blah blah) 10:50, 18 February 2011 (UTC)[reply]

February 16

Did IBM Watson take the lead tonight on Jeopardy! ?

I missed the show. Thanks. 76.27.175.80 (talk) 01:24, 16 February 2011 (UTC)[reply]

Usually the relevant articles for such things are updated quite promptly with current events: See Watson (artificial intelligence software). Short answer: it ended the first match with over three times the amount of the next contestant, although it botched the Final Jeopardy question (In the category "U.S. Cities", it answered "Toronto"), losing only $947. -- 174.21.250.120 (talk) 05:24, 16 February 2011 (UTC)[reply]

Error while calculating Windows Experience Index in Windows 7

I am using Windows 7 and when I try to calculate the WEI, I get the following error message:

Cannot complete assessment. The assessment or other operation did not complete successfully. This is due to an error being reported from the operating system, driver, or other component.

I tried updating all drivers by going to the Device Manager. I also do not have Kaspersky antivirus installed (I learnt from a forum discussion that Kaspersky might be the cuplrit). But I still have the error. Due to this error, I am not able to apply the Aero effects onto my system. How can I calculate the system rating? Please help me. Thank you very much. —Preceding unsigned comment added by 125.16.180.5 (talk) 07:51, 16 February 2011 (UTC)[reply]

extract text from PDF

Hi I have a PDF file with a lot of tabular, columnar information. There are columns with characters and some with numbers. I would like to extract all of this into text, but when I choose 'save as text' it saves all the text separated by spaces... so that's pretty useless because I don't know which column it belongs to. I was thinking about selecting a column at a time and copy/paste but the alt-left-click doesn't allow scrolling down the file. Any ideas on how to get the PDF into fixed-format text or even better, comma-delimited? Sandman30s (talk) 07:54, 16 February 2011 (UTC)[reply]

It depends on how the PDF was created. Sometimes it records structural information, sometimes not. My first run at it would be to use a PDF->HTML converter that would make column extraction easy. Failing that, I would look for or write some software that would guess at the columns based on where the bits of text are. --Sean 14:11, 16 February 2011 (UTC)[reply]

If the text is separated into columns by spaces, would the Text-to-Columns feature in Microsoft Excel work? Kingsfold (Quack quack!) 14:49, 16 February 2011 (UTC)[reply]

I suggest opening the PDF in Inkscape. You will likely have better access to getting the columns of text out of the text box itself than the document viewer. -- kainaw ™ 14:57, 16 February 2011 (UTC)[reply]

If it is not too many tables I usually copy-and-paste the text into Notepad. Then it is easy to see if there is really a tabular structure to the text. If there is, and you are not lucky and get tab characters between the columns, I usually remove any spaces within fields manually (for example, "United States"-->"UnitedStates". Then, I copy and paste the data into Excel, where the "import text" feature comes up automatically and I can choose space as a column separator. Not too elegant, but always fastest for small operations. It's hard to standardize this in any case as the structure of PDF documents can differ a lot. Jørgen (talk) 20:25, 16 February 2011 (UTC)[reply]

Thanks for all the help. I managed to find a PDF to Word converter and got it into a program-readable CSV thereafter. To Jørgen, no, the file was way too big to use the method you described. Sandman30s (talk) 10:27, 17 February 2011 (UTC)[reply]

VuDroid

The pdf pages overlap vertically. Can you help me? --83.103.117.254 (talk) 08:03, 16 February 2011 (UTC)[reply]

Probably the best thing to do is to file a bug with that project here. You should link to or attach the document in question. --Sean 13:58, 16 February 2011 (UTC)[reply]

GPS

I have planned to buy the GPS monitor shown here.I am not subscribed to any GPS service or satellite etc. Will the monitor still work for me ? ( I am in south of (India's) Punjab) Jon Ascton (talk)

You do not need to subscribe or pay for GPS service. The satellites are already in orbit, and they broadcast their signals free of charge. Some users, particularly the military, use different signals (or, the same signals with different decoding technology that isn't available for sale to the general public), to obtain better quality position information - see military GPS signals - but anyone can receive all of the signals. Nimur (talk) 17:46, 16 February 2011 (UTC)[reply]

I don't believe that the miltary get better positional information - this was the case with Selective availability but this is no longer used. --Phil Holmes (talk) 10:31, 17 February 2011 (UTC)[reply]

However, some GPS mapping providers charge for updates to maps when new roads are built, and for live traffic information, to help you avoid the jams. Others do the routing on a central computer, instead of on the device (Android Maps for one). For any of these services, you'll need to take out the subscription. CS Miller (talk) 19:30, 16 February 2011 (UTC)[reply]

How does IBM's Watson choose the categories and dollar amounts on Jeopardy?

I haven't been able to find any answer or reference for this question, so hopefully someone can provide the answer or direct me to the right resource. Watson's algorithms for answering the questions themselves have been nicely discussed on many sites, including IBM's own Watson site and the recent PBS NOVA special. However, I haven't heard any explanation of how Watson chooses which category to select, nor how Watson chooses the dollar amount to select within the category. Is Watson choosing by itself? If so, how? Or is a human "behind the scenes" making the selections for Watson? Similarly, how is Watson choosing the dollar amounts to bet in both Double Jeopardy and Final Jeopardy? The amounts that Watson bet on the show last night were very strange--almost random, and not something that a human would choose. Just curious if there was some sort of coded-in strategy for this aspect of the game. --Zerozal (talk) 17:43, 16 February 2011 (UTC)[reply]

All the public information about Watson is available from IBM at the IBM Watson website. I haven't watched all the videos explaining how he works, but I would posit that estimating confidence in an answer is easy, based on statistical results of earlier answers - so to pick a category, Watson can select the category he is most confident in. Or, Watson may use an elaborate game theory model to defer using "preferred" categories until a more optimal time. Nimur (talk) 17:49, 16 February 2011 (UTC)[reply]

I looks like they do some basic game-theoretical stuff. If my calculations based on the information at j-archive are correct, Jennings' total score could have maxed out at $41200, had he wagered everything (and gotten it right, which he did), and Watson's wager was such that, had it lost, he'd've had totaled $41201. Of course, the reason Watson had to wager a wacky number to make that come out right was because it had a wacky score from Double Jeopardies where it wagered wacky amounts. Probably that's because they've worked out some kind of function that takes as input the Watson's estimated likelihood of getting the answer right, and then they round it to the nearest dollar. Paul (Stansifer) 02:35, 17 February 2011 (UTC)[reply]

This post describes Watson's wagering strategies for both Daily Double and Final Jeopardy questions. --LarryMac | Talk 17:59, 16 February 2011 (UTC)[reply]

Thumbnail images in Windows Vista

My laptop runs Windows Vista, and whenever I want to view photos in Thumbnail mode, I am unable to see previews; I have to open each individual file to see my pictures. Do I need to change a setting to see the previews? Alternatively, is there a third-party application that I can install? Currently all I see is a generic view of an island. Hemoroid Agastordoff (talk) 17:55, 16 February 2011 (UTC)[reply]

In "Folder options" (the view tab), the option to "Always show icons, never thumbnails" needs to be unchecked. Showing thumbnails can slow down the browsing of folders, so this option is provided for slow computers. Dbfirs 09:45, 17 February 2011 (UTC)[reply]

Thanks, Dbfirs, you've made my day ! Hemoroid Agastordoff (talk) 15:31, 17 February 2011 (UTC)[reply]

Standby

Resolved

Is there a way to make a computer running Windows 7 go into standby or some other similar mode where the hard drive and processor etc power down, but keep the screen on and displaying something? 82.43.92.41 (talk) 23:00, 16 February 2011 (UTC)[reply]

No, the processor is needed to generate the image you see on your screen. Looie496 (talk) 23:12, 16 February 2011 (UTC)[reply]

(ec) No. Even with fancy ACPI power management technology, and even with smart graphics processors, the CPU is still required to put pixels to the screen (or to command the GPU to do it by proxy). There are no "personal computer"-style machines that can power down the CPU and still keep an image on the display screen. Some e-book readers may have a capability to do what you want. Nimur (talk) 23:13, 16 February 2011 (UTC)[reply]

Ok 82.43.92.41 (talk) 23:15, 16 February 2011 (UTC)[reply]

Well, technically, most new monitors display something when they are powered on, but do not receive a signal. For example, something like this: [12]. decltype (talk) 09:36, 18 February 2011 (UTC)[reply]

True; technically, most monitors contain a fully configurable and programmable computer inside them, too: a Video Display Controller resides on the monitor-side of the connection, and buffers, and then decodes, VGA or DVI or HDMI signals. Ironically, this means that in a modern PC, using a VGA connection to an LCD monitor, the signal is digitally generated by software on the CPU, copied to RAM, sent through a peripheral bus like PCIe, sent to a GPU bus controller, copied to video ram, converted to an analog signal by a RAMDAC, sent in analog format to a video controller, re-digitized/resampled, re-buffered, and finally displayed on the screen. And this doesn't even count video/GPU processing. Every single pixel of every frame is passed through this pipeline when the CPU is in control of the screen buffer. Most users, running most operating systems, on most hardware, are not able to micromanage the entire video-pipeline, but conceivably, a skilled programmer with the appropriate driver toolkits and reasonably configurable hardware, could subvert the "conventional flow" to perform a task similar to what the original questioner wanted. Frankly, such technology baffles me, and I wouldn't want to be the person who has design it. Nimur (talk) 22:02, 18 February 2011 (UTC)[reply]

February 17

Generic DVD/RW software for Win XP

I've just got myself an Acer Aspire netbook, and am trying to persusade it to recognise an ancient external Freecom classic series DVD/RW. I know I looked some time ago for software/drivers for this, but couldn't find any - eventually, I found a generic driver somewhere, but I haven't a clue where. Does anyone know where I can find one?,/s>

The netbook recognises the DVD writer as a CD drive only at the moment, but I've definitely had it working before - unfortunately, this was on my desktop PC, which seems to have given up the ghost, so I can't see what software I was using :( AndyTheGrump (talk) 01:51, 17 February 2011 (UTC) [reply]

Scratch that: It seems to recognise the DVD/RW now, or at least, it reads DVD's ok - I think I'll need to find DVD writing software, but that is less urgent. AndyTheGrump (talk) 02:45, 17 February 2011 (UTC)[reply]
~~One free option for the software is CDBurnerXP (if you're using pretty much any version of Windows) which burns onto CDs, DVDs, etc. ZX81 ^talk 12:15, 17 February 2011 (UTC)[reply]~~
~~Another alternative is Infrarecorder, which is free. -- Finlay McWalter ☻ Talk 15:20, 17 February 2011 (UTC)[reply]~~
~~Thanks, I'll take a look at both - Infracorder sounds familiar, that may have been what I'd been using previously. AndyTheGrump (talk) 20:54, 17 February 2011 (UTC)[reply]~~
~~There is also ImgBurn. Reviews are here: http://www.techsupportalert.com/best-free-cd-dvd-burning-software.htm 92.24.182.65 (talk) 21:45, 17 February 2011 (UTC)[reply]~~
~~How do I save an LUA file as an LUA file in Vista?~~
I want to edit a small lua file for an RTS mod that I play, but Vista brings up an error message something along the lines of "cannot specify path or make sure specific path is correct" every time I try to save the edited file. Even when the file is unedited it won't let me save. I just want to edit the lua file and save it, how can I do that? --Ye Olde Luke (talk) 04:47, 17 February 2011 (UTC)[reply]
Are you able to get to the Save As dialog where you can specify a save location? Does it allow you to save in the Documents folder or on the desktop? I know lua files often have to be saved in a sub-folder of the game's application folder (sorry, the technical term has deserted me!). Vista can be very protective of folders under Program Files, and I often had to save my addon files elsewhere, moving them to the correct folder as an admin user afterwards. --Kateshortforbob _talk 13:18, 17 February 2011 (UTC)[reply]
~~Drive size increases after copy then delete files~~
Okay. Just make it simple with a small example. This morning I move 25 GB of data from D: to E: before formatting D:, to get rid of some garbage files created by the Windows System Image that I cannot see (even if system hidden file are shown). After everything is done, I move those data back. Now the E: drive size increases by 47 MB. 47 MB is not too serious for me, but I really want to know where and why it is gone. Not only this morning, I have seen that phenomenon for several years w/o a reason. Only when I format the drive, the wasted space created by deleting files is restored. If I remember correctly, this does not happen on drive with FAT32 file system. My flash drive for example; its size always changed to 4096 bytes each time I deleted all data on it. -- Livy the pixie (talk) 08:12, 17 February 2011 (UTC)[reply]
If I were to hazard a guess I would say that the space was used up by Windows Advanced Indexing which didn't clean up the newly allocated space once the files were deleted again. You can turn indexing off if you really want, but I wouldn't recommend it as that feature is used to improve the speed and stability of your system. It's also possible your page file could have increased in size. Sandman30s (talk) 10:38, 17 February 2011 (UTC)[reply]
No, I use no page file at all. I would like to used raw RAM because I think it is faster, and my computer RAM is large enough to be used without page file. I have heard a thing or two 'bout the Indexing thing but maybe I need to study it further. Just googling around, but 'till haven't found the answer yet. Btw, anyone can try copy about 1 GB data or larger to a drive and then delete it to see the result. -- Livy the pixie (talk) 10:55, 17 February 2011 (UTC)[reply]
The Master File Table has a 1-kilobyte entry for each file on the disk. It's expanded as necessary and (I believe) never shrunk. If you moved 48,000 files or so, that could be the explanation. Later files created on the volume will reuse those MFT entries. -- BenRG (talk) 11:20, 17 February 2011 (UTC)[reply]
Personally I think you should not worry about any of this. In an era when 2TB drives cost US$80 or US$90, why get all OCD about the issue to the point where you are actually formatting drives to try to reclaim an amount of space that is tiny by today's standards? You should also use a page file, by the way; it shouldn't slow down your system in your case. Comet Tuttle (talk) 17:42, 17 February 2011 (UTC)[reply]
Windows XP had/has an annoying habit of discarding perfectly good pages when the system is idle even when there's no memory pressure. I often had the experience of leaving my computer to get a cup of coffee, returning, and having to wait several seconds while the stupid thing paged in the application I had just been using. I disabled the swap file and the problem went away, with no apparent downside. This might be fixed in Windows 7; I don't know because I've never attempted to use a swap file in Windows 7. RAM is cheap too... -- BenRG (talk) 21:12, 17 February 2011 (UTC)[reply]
This page at Coding Horror hosts part of a fierce debate on this issue. One somewhat obscuring fact is that Windows 7 is a very active disk cacher and whatever RAM you have that is unused will rapidly be used for disk cache, which may make measurements harder. Personally I would always choose to have a disk cache, even a 1 byte disk cache, if it were feasible, because I would prefer to never ever seen an "Out of Memory" error again in my whole life; having disk cache on simply prevents this. (Obviously by growing my 1 byte page file to whatever size was needed, when it was needed.) And if you've got so much RAM, your OS should never be hitting the page file anyway. If, as you say, the OS behaves itself well. Comet Tuttle (talk) 21:25, 17 February 2011 (UTC)[reply]
I disabled it because I hate the way Windows manage page file. If you had 2 GB RAM, it set the page file to 2 GB, and if you had 4, it set the page file to 4 (logically it must set the page file smaller because you have more RAM). I encounter no issue on my desktop with 4 GB RAM but my laptop with 2 GB RAM crashed when I opened 8 → 10 tabs on IE silmutaneously, so I was forced to set it to 1 GB. -- Livy the pixie (talk) 04:07, 18 February 2011 (UTC)[reply]
Windows has two sizes for files - the actual number of bytes in the file, and the space used on disk. Depending on file, sector and cluster sizes there can be quite a discrepancy. If a disk has 1024 byte clusters, then a 1025 byte file will consume 2K of disk space, even though Windows will still report that it is a 1025 byte file. If you delete that file, then the free space on the drive will be (previous free space + 2K). --LarryMac | Talk 20:22, 17 February 2011 (UTC)[reply]
That's true, but it can't explain the missing 47 MB. -- BenRG (talk) 21:12, 17 February 2011 (UTC)[reply]
There's a general trend in the design of computer systems to build things that have more and more nice properties (reliability, good performance in corner cases, etc.), at the expense of predictability. FAT32 is not a journaling file system, so it's simpler in behavior, but breaks more and worse. Paul (Stansifer) 20:53, 17 February 2011 (UTC)[reply]
Almost forgot. If you deleted a single 7.8 GB DVD9 ISO image, the drive size increased only by a few bytes. But if you deleted several thousands files with total size of 500 MB, the drive could waste up to 10 MB (Approximately. The point is that the more files are deleted, the more space is wasted. The wasted space does not depend on the file size, but on the number of files). Oviously 47 MB is too tiny by today standards, and I do not format the drive to recover it. Just because I want to know why it vaporizes into thin air. -- Livy the pixie (talk) 04:07, 18 February 2011 (UTC)[reply]
If it's ~1K per file, then it's probably the MFT (see above). -- BenRG (talk) 06:33, 18 February 2011 (UTC)[reply]
It sounds logical. But are you sure later files created on the volume will reuse those MFT entries? -- Livy the pixie (talk) 08:08, 18 February 2011 (UTC)[reply]
~~WYSIWYG Wiki Editor~~
~~Is there WYSIWYG Wiki Editor that can be used in a web browser to create/edit, even in offline and later submit to Wikipedia?~~
There was a big effort to do something like that in browser Javascript but I don't know its current status. I just write wikitext in emacs (i.e. so I see the markup, not wysiwyg) and it works fine. Wysiwyg is overrated unless you have no experience with wiki markup. 71.141.88.54 (talk) 11:41, 17 February 2011 (UTC)[reply]
Wikia.com uses a wysiwyg editor. I hate it. I refused to use wikia until they offered an option to turn off the wysiwyg editor, allowing users to use wiki markup. -- kainaw ™ 13:40, 17 February 2011 (UTC)[reply]
~~Kaspersky Internet Security fouling up my devices~~
I recently plugged my Archos 28 Internet Tablet into an XP computer running Kaspersky. Kaspersky decided to wipe all the data from the device because it was allegedly a virus. I got it all restored, but it started behaving rather oddly; the folders wouldn't display a "folder" icon but instead a 'unknown file type' one. They'd always open in a new window. Now it won't let me add or delete files on other systems because the disk is "write protected," and something similar's also happened with a SanDisk Cruzer Blade USB stick I've been using.
What can I do? 122.174.98.39 (talk) 11:57, 17 February 2011 (UTC)[reply]
Well, an obvious thing to try is to uninstall Kaspersky and install some different antivirus software, and see if that fixes your problem. List of antivirus software is a good starting place. Comet Tuttle (talk) 17:39, 17 February 2011 (UTC)[reply]
~~Graphics/visualization question: converting vector field samples into continuous streamlines~~
Say you have a 2-D vector field sampled regularly at grid points. How do you convert the samples into continuous streamlines(?) for visualization? Thanks in advance. --173.49.19.81 (talk) 12:57, 17 February 2011 (UTC)[reply]
Are you asking for a "general solution" or a specific software program that can do this? Here is software to draw arrows in FORTRAN90, in MATLAB using the quiver command; in the free software GNU Octave you can also use quiver. If you want streamlines you must numerically integrate the ordinary differential equation whose gradient is expressed by the vector-field; and iterate over initial-values for each streamline you want to solve. This is a bit tricky, because in pathological cases the solutions will be unstable (and streamlines will cross - which is an unphysical result). For this reason, you should not use a simple forward-difference integrator (like an euler method) - though you can try, and see if it works. In MATLAB, you can use ode23 or the other sophisticated higher-order Runge-Kutta methods to stably integrate most vector fields. In FORTRAN-90, you can use your favorite numerical solver code, such as this RK-45 solver from Iowa State University. To make matters more complicated, if (as you say) you have sampled the vector field (and cannot explicitly calculate it at every point) you must interpolate the values between sample-points so that an integrator can solve the streamline. The method you choose for interpolation can influence stability and convergence, not to mention physical interpretation of the streamline. If you are lucky enough to have MATLAB, you can use the Streamline program to perform all of these steps for you. I do not believe GNU Octave supports this command yet ((streamline) is reported "unimplemented" still). For obvious reasons of complexity, it is non-trivial to implement this in general. Nimur (talk) 20:47, 17 February 2011 (UTC)[reply]
~~Valve holder tax~~
In the Radio receiver design#FM vs. AM article there is mention of an "valve holder tax" that the UK goverment imposed. What were the reasons behind this tax?, and time period? I did some net searches, but no qualified answer were found. Electron9 (talk) 13:12, 17 February 2011 (UTC)[reply]
The reason behind this tax was simply to raise revenue. No different from the Hearth tax, and Window tax. People who choose to have more than fire place, or think they 'need' more than one window, or even have a radio with more than one thermionic valve socket, obviously have more money than sense! Therefore, their government obliges them to pay even more for the said items. With the money so collected, those who have the onerous duty to run the country, can then spend the money more wisely - on such things as foreign visits, commissioning statues of themselves and cultural enriching things that the tax payers themselves are not capable of appreciating. Germany imposed a similar tax.Vacuum_tube#Other_variations. Simple really.--Aspro (talk) 20:55, 17 February 2011 (UTC)[reply]
~~Which time period?, and how muchdid the goverment charge?, used other countries? Electron9 (talk) 10:17, 18 February 2011 (UTC)[reply]~~
Aspro: do you have any evidence that the UK valve holder tax was intended to raise revenue and not e.g. to fund radio services?

I can't find any evidence that there was a valve holder tax in the UK. Googling "valve holder tax" returns only pages that scraped that Wikipedia page. I found a discussion that explained that sales tax was payable on valves for home use in radios but not for commercial/industrial use in other products; this is consistent with having a tax on finished products but not on raw materials or components (the current UK value-added tax uses a different system to the same end.)[13] However, early 20th century taxation policy may not be well documented online, so it's possible the tax did exist for a while.

Regardless of the valve-holder tax, the UK had a radio tax in the mid 20th century (1922-71) which was used to fund the BBC: you had to buy a radio licence to own a radio in the UK. In the earlier years, a licence for a home-made radio was more than that for a pre-built radio bearing the BBC brand (again this may have been transformed into memories of a tax on valves). There was an additional tax payable on the licence from 1957 to 1964 which went to central government, but most of the time all the money went to the BBC. The licence is briefly mentioned in Television_licence#United_Kingdom but my main source is[14]. --Colapeninsula (talk) 10:38, 18 February 2011 (UTC)[reply]
Home brewed radios were certainly more expensive to build from purchased parts. One had to buy the components as if they were spares (and also pay purchase tax on the higher prices). Even from a wholesaler willing to give a discount off the list price, it would still cost a little bit more. Still, if one just bought the valves, most of the other bits could be scrounged or made in garden shed for naught. --Aspro (talk) 18:15, 18 February 2011 (UTC)[reply]
~~Crossword puzzle generators~~
Hi, I'm wondering about crossword generation software, preferably for Windows (but Linux is fine too, as long as it has a GUI) and definitely not online. I used to have a program on my old Mac OS 9 machine (archaic, I know), that did exactly this but I can't remember what it was called. It updated the puzzle as you were typing, so you could see the layout of the puzzle while you were making it. Thanks :) XRDoDRX (talk) 14:45, 17 February 2011 (UTC)[reply]
I use Crossword Compiler. I think it only has British English but I could be wrong and it might not matter that much depending how you want to use it. There are others available if you search the web.--Shantavira|^{feed me} 16:17, 17 February 2011 (UTC)[reply]
~~Keyboard/start-up problem~~
I have a Dell Latitude D620 laptop and run Windows XP that requires me to do a control-alt-delete after a start-up. The problem is that when I press the control-alt-delete buttons, nothing happens and I can't get use the laptop. Obviously, I'm on another computer now. Does this mean that I have a bad keyboard, or is there something else I can try? Thanks for any help. 71.125.146.152 (talk) 16:05, 17 February 2011 (UTC)[reply]
A few things to try
Do the other Ctrl-Alt-Del keys work? Either the left or right Ctrl and Alt keys, and either the Delete or NumPad Del keys will normally work.

Does an external USB keyboard work?

Do the NumLock/CapsLock keys work?

Try pressing F6 after the BIOS screen clears; you should drop into the Windows Boot Loader; does Ctrl-Alt-Del reboot the laptop here?

CS Miller (talk) 16:22, 17 February 2011 (UTC)[reply]
Thanks for the quick reply. I tried those options, and none worked. I was finally able to get through to my employer's IT people and was told the keyboard is not functioning because I can't even start up before Windows begins running. They're sending me another. Again, thanks for your help.71.125.146.152 (talk) 16:53, 17 February 2011 (UTC)[reply]

What you can try is to power off the PC. Take out the battery and the cord and hold the power button for a minute. That resetted the keyboard for me when it was not working. --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 21:14, 17 February 2011 (UTC)[reply]
This sounds like you've run into a rather common problem with the Dell D-series laptops...I did tech support for C-Series and D-series laptops for a couple of years, I've seen that issue countless times. The problem is that the keyboard connector on the motherboard is just badly engineered and the cable will occasionally come off. The easy fix is to remove the keyboard (there are a couple screws marked with "K" for keyboard on the back, just unscrew these and you can lift off the keyboard), then unplug and firmly reseat the keyboard cable. If you haven't sent it off to your support people yet, that's definitely something you should try. -- Ferkelparade π 09:18, 18 February 2011 (UTC)[reply]
~~IBM Watson~~
~~Is IBM Watson an OS or just a program running on an OS? --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 20:56, 17 February 2011 (UTC)[reply]~~
We have an article on Watson (artificial intelligence software), although it doesn't answer this question directly. Personally, I'd say that Watson is an application running on specially configured hardware, and most likely running a customized version of whichever OS IBM typically supplies with the Power7 hardware. --LarryMac | Talk 21:04, 17 February 2011 (UTC)[reply]
~~This type of diagram may be misleading you.~~
I thought WATSON was an OS since only an OS has direct access to all the hardware components --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 21:11, 17 February 2011 (UTC)[reply]
The article does answer this directly — Watson runs on the SUSE OS. It's an application. Why would you assume Watson needs "direct access" to any hardware component? Comet Tuttle (talk) 21:12, 17 February 2011 (UTC)[reply]
Damn, I read right past that at least four times. My bad. --LarryMac | Talk 00:01, 18 February 2011 (UTC)[reply]

Because than it can harness the raw power of the CPU and graphic chips (assume WATSON has one) --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 21:15, 17 February 2011 (UTC)[reply]
I think that diagrams like the one to the right (which I found in our operating system article) may be misleading you a bit. It's true that an OS is allowed to execute certain CPU instructions that an application is not allowed to execute, but the CPU still directly fetches each instruction in the Watson code and executes it directly, and stores the results directly into memory. Being an OS wouldn't speed up Watson any more. Comet Tuttle (talk) 21:34, 17 February 2011 (UTC)[reply]
If the machine has special hardware designed for your application (which Deep Blue certainly did, but I don't know about Watson), one does normally need kernel privileges to use it, but the usual practice is to write most of the software as a normal application, except for a small device driver that runs in the kernel and passes application data to the hardware and vice versa. -- BenRG (talk) 22:55, 17 February 2011 (UTC)[reply]
Operating systems don't possess any inherent power that applications don't have. They can deny powers to applications (if the user so desires); this is useful for security. But it's best to think of the operating system as an abstraction layer: it allows each program to run as though it were the only program running on the machine, and without having to know the details of the particular machine. Even though the Watson software was purpose-built for one machine and that machine had only one use, it turns out that writing software in this way is much easier than writing it without an operating system, because the imaginary simple machine that the OS presents to the applications is nicer than the real machine. Paul (Stansifer) 05:11, 18 February 2011 (UTC)[reply]
There's nothing magical about operating systems. They're just programs like applications are. The only technical difference is that they run directly on the hardware, but it's actually technically possible to run any program directly on the hardware. Today's computers are so complex that writing an application running directly on the hardware is quite difficult compared to writing one running on an operating system, but in the past, it was common to write custom programs that ran directly on the hardware. The answer to the original question is that WATSON is most probably an application running on an operating system. JIP | Talk 08:15, 18 February 2011 (UTC)[reply]
A technical whitepaper is available from IBM at http://ibm.com/watson - you may need to create a free IBM-login if you don't already have one. Watson is written in Java - so technically, IBM Java Runtime Environment is the "operating system," though the IBM JVM resides on top of IBM Linux on IBM Power7-750 systems, with a variety of other IBM and free/open-source software. For example, the Hadoop and Apache UIMA technologies make the system work as a whole. With clusters of computers, it's often difficult to describe "operating system" in terms that the average PC-user will quickly understand (because - it isn't exactly clear if the "computer" is distinct from the "ensemble of computing nodes" - especially if each node is a fully-capable computer on its own). If I were to describe the OS, I would say it is "Apache httpd, plus the IBM J2EE environment." I would not include Linux as a description of the operating system of Watson, because he could be trivially ported to any other computer platform that supports Apache and J2EE. In the case of the machine we saw on television, "Linux" is really just a very sophisticated device driver for a handful of CPUs and a little bit of RAM; the operating system is the Java environment that harnesses hundreds of Linux devices and assigns tasks to them. Nimur (talk) 16:53, 18 February 2011 (UTC)[reply]
~~WATSON interface~~
What does IBM WATSON GUI looks like? Also I read in the comment that WATSON crashed during the games. Is this true? --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 23:13, 17 February 2011 (UTC)[reply]
There may not be one. Watson's job is to consume a chunk of text and produce another chunk of text. Programmers are used to working with command line programs, and Watson's task fits that ideally. Of course, there's a great deal of complexity between input and output, and we can only speculate on all of the diagnostic and control tools that the engineers had access to. A software project like Watson probably has a single large piece of software and a cloud of (partially) independent tools. Each of these can be operated by a human, and probably some of them allow a person to drive the whole thing in a simple way (useful if some person comes visiting and wants to see a demo, instead of the charts and graphs and benchmarks that the engineers have been staring at for weeks as they struggle to improve the system).

I hear the rumor that Watson kept on crashing during the game, also. It seems odd to me because IBM's researchers clearly know how to write software, and the problem probably lends itself to a (relatively) stateless (and perhaps even nicely modular) design, which would make it easy to write reliable code. But I don't know anything about the problems they faced. Paul (Stansifer) 05:39, 18 February 2011 (UTC)[reply]
Where does that rumor come from? IT seems like no one outside of IBM would actually know that. APL (talk) 06:13, 18 February 2011 (UTC)[reply]
It might be a throwback to the Kasparov match. One of the criticisms of Deep Blue was that the programmers manually altered the system between matches to incorporate fixes to defects discovered during play. The fact that the rumor takes off could be feeding off of that, with the thought that "well, the computer didn't really do it on its own, it needs constant attention of people to work". Sort of a pro-human/"humans *aren't* obsolete" ego boost. Pretty much the same reasoning behind the criticisms that the match wasn't fair because Watson got the clues in the form of a text message instead of having to do audio processing/OCR of the monitors. -- 174.21.250.120 (talk) 18:04, 18 February 2011 (UTC)[reply]
I don't think it's a rumor. My understanding is that the PBS people filming the game encountered frequent delays because of problem with a computer. They incorrectly assumed that it was the IBM machines running Watson that was at fault, but later clarified that it was actually the computer that passes the questions to Watson. Predictably, the press ran the story without doing any research into whether it was true or not. On a side note, the cluster running Watson is built from Power 750s. If they are like earlier models, restarting them after a crash is not a trivial matter as it is with PCs, its an approx. 30-minute affair due to diagnostic checks. Rilak (talk) 07:27, 18 February 2011 (UTC)[reply]
It's also worth noting that IBM software is, unlike many commercial "consumer" tools, usually subject to extremely high uptime requirements. Now, Watson was a research project, but he was still designed in the same environment. During my (brief) time at IBM, I recall the motto, "high performance, high uptime, high availability," in reference to our computers and our engineers. You can read about High Availability Services at IBM's website. Mean time between failure is often quoted in years or even decades. (Again, let me re-emphasize - this is not your average Windows PC). It sounds very dubious that the software, hardware, or anything else, would crash during the game show. What I might believe is that "performance degradation" occurred as a result of software or hardware error, but IBM Tivoli restarted the derelict server software. (Another thing I learned from IBM is that there's no such thing as a "crash" or a "failure"...) Nimur (talk) 16:35, 18 February 2011 (UTC)[reply]
Regarding the GUI, it is probable that Watson uses the IBM variant of the Eclipse platform. IBM uses Eclipse to develop and to deploy almost all of its software. It is very likely that an Eclipse plugin communicates to a set of IBM server-utilities to monitor status. Nimur (talk) 16:39, 18 February 2011 (UTC)[reply]
~~February 18~~
~~Good Alternatives to file and folder shortcuts on a USB flash drive?~~
When trying to keep track of hundreds of files on a USB flash drive, I usually organize the files into a tree structure with folders named after topic or theme. I use quite a lot of folder and file shortcuts back and forth between the various folders.
It works fine until I plug my portable USB drive into another computer where it suddenly no longer is called "E:\", but instead "G:\" or "I:\" or whatever. This renders all my file shortcuts useless. ;-(
Of course, the same thing also happens when I copy a directory tree to another disk.
(I currently use WindowsXP but I would like the solution to be platform independent).

Could you please give me some advice or ideas to how I might solve or avoid this problem?
--Seren-dipper (talk) 13:42, 18 February 2011 (UTC)[reply]
The easiest thing to do might just be to a pick a drive letter that's not in use on the computers you usually use and then change the USB drive to that letter (Control Panel -> Administrative Tools -> Computer Management -> Disk Management or just Start->Run->diskmgmt.msc). Of course that won't work if you go to a computer that has the drive in use, but if you use the same computers regularly this could be the easiest solution. ZX81 ^talk 14:41, 18 February 2011 (UTC)[reply]
Or you could use subst to create a substitute drive letter of your choice on the computer which maps to the usb drive letter. There's a nice gui version here which is portable too so you could keep it on your usb drive ready to use on any computer. Both methods probably require admin privileges on the computer you use them on, so might not work on public or restricted computers. 82.43.92.41 (talk) 14:48, 18 February 2011 (UTC)[reply]
Great answers! Thank you!
--Seren-dipper (talk) 19:46, 18 February 2011 (UTC)[reply]
~~How may I "update" file shortcuts?~~
Now, do you have any suggestions for how I may "update" drive letter and/or path for all file and folder shortcuts when (or after) moving a directory (including all subdirectories) into a new drive and/or into another location within the directory tree structure?
--Seren-dipper (talk) 19:46, 18 February 2011 (UTC)[reply]
~~Identifying disks on Linux, similar question to the above~~
The question above about USB drives on Windows made me think that the same kind of thing would happen on Linux. Linux identifies drives in the order it finds them, assigning them labels such as /dev/sda, /dev/sdb and so on. My current computer has two internal hard drives, so a USB drive would be /dev/sdc. But suppose I added a third internal hard drive - this would cause USB drives to become /dev/sdd instead, causing the ready-made mountings in /etc/fstab to become useless for this purpose. Is there some way in Linux to mount filesystems by the actual disks they're on, not by the device Linux happens to assign them? JIP | Talk 14:32, 18 February 2011 (UTC)[reply]
On my (Ubuntu) system, there are automatically constructed symlinks in /dev/disk/by-label/, so that you can talk about your partitions by what they're labeled, rather calling them /dev/sd?. Ubuntu also automatically handles mounting (also using labels) in some magical fashion I don't understand, so I've never had to touch my /etc/fstab. Paul (Stansifer) 15:13, 18 February 2011 (UTC)[reply]
In Fedora and Redhat, I have /dev/disk/by-id, by-label, by-path, and by-uuid. So, there are many options for identifying a disk other than using the sdx option. However, as Paul stated, Linux auto-mounts removable media by itself, so there is no need to add USB drives to fstab. -- kainaw ™ 16:15, 18 February 2011 (UTC)[reply]
Minor quibble: I don't believe "Linux" (the kernel) performs any auto-mounting. gnome-volume-manager, which is running by default in Ubuntu and many other Linux distributions, auto-mounts disks. If you use Kubuntu, a different mount service manager may be running; and if you use a different version of Linux, you might not have any auto-mounting functionality at all. Nimur (talk) 16:43, 18 February 2011 (UTC)[reply]
As Kainaw notes, partitions can be mounted by UUID. They appear in /dev/disk/by-uuid, and you can (I guess, I've never used that method) specify that explicitly in fstab. An alternative is to use the UUID= syntax in fstab, which does the same thing. So my own fstab looks like this:
# boot partition UUID=40cdfe04-298a-4ac6-919c-11c88e451a06 / ext3 relatime,errors=remount-ro 0 1 # swap UUID=8c3f96ba-e5f6-4a52-9162-fe33a7d077b2 none swap sw 0 0
This survives all kinds of disk rearrangements. Because the UUID corresponds with the partition (not the physical disk) one can dd a drive's contents to a bigger drive, unplug the old, and the system boots as before, with no change to fstab. -- Finlay McWalter ☻ Talk 17:05, 18 February 2011 (UTC)[reply]
~~The manual page for mount(8) recommends the UUID= method over the /dev/disk/by-xxx method. -- Finlay McWalter ☻ Talk 17:13, 18 February 2011 (UTC)[reply]~~
~~Installing Fedora 14 with every single package?~~
Suppose I were to install Fedora 14 64-bit version with every single package that comes on the install DVD. Roughly how much space would that take on the install partition? JIP | Talk 17:14, 18 February 2011 (UTC)[reply]
My vague guess/memory is in the 6-8 gb range. The dvd is something like 3.3gb but a lot of the content is compressed. You'll want to install more stuff beyond the dvd, though, and have some space left for swap and user files. 71.141.88.54 (talk) 11:25, 19 February 2011 (UTC)[reply]
~~Best choice of writeable DVD disc types~~
I'm in the process of moving a writeable DVD drive from another old computer to the old computer I use. It will be able to write DVD+RW, DVD-RW, and DVD-RAM. Which of these discs would be the best choice to buy and use please? I am going to verify what is written to disc, and it would help if any faults could be corrected. Thanks 92.28.240.53 (talk) 17:15, 18 February 2011 (UTC)[reply]
Our article DVD+R lists a few ways that DVD+R is allegedly superior to DVD-R, at a cost of being able to store slightly less data. Comet Tuttle (talk) 17:53, 18 February 2011 (UTC)[reply]
I agree with above statement. If in dault, read the specification. Of course don't forget the "made in China" warning label :-) Electron9 (talk) 18:17, 18 February 2011 (UTC)[reply]
Electron9's being amusing, but he's correct that there's cheap media and more-expensive media, and I've seen a lot of people online blame cheap media for discs going bad within a short time. Note that our various articles about DVD recordable formats say DVD-Rs and DVD+Rs may have a lifespan as short as a couple of years. I also note that our DVD-RAM article has claims of superior reliability and length of data storage compared to DVD-R and DVD+R, but I have no experience with DVD-RAM, and that article does need some more citations. Comet Tuttle (talk) 18:44, 18 February 2011 (UTC)[reply]
~~I didn't ask about DVD-R or DVD+R, but DVD+RW and DVD-RW and DVD-RAM. 92.29.119.194 (talk) 23:45, 18 February 2011 (UTC)[reply]~~
It is claimed that DVD+RW has better error-tolerance during the read and write process; for example, see this review from Tom's Hardware. In practice, the distinction is moot. Use caution with DVD-RAM, because while many DVD drives can read the entire set of DVD-R, DVD+R, DVD-RW, and DVD+RW, fewer drives can read DVD-RAM. Nimur (talk) 00:04, 19 February 2011 (UTC)[reply]
(ec) Pressed DVDs and DVD±R[W] all use the same on-disc format for the recorded data. DVD–RAM is completely different. You can't make DVD-Video discs using DVD–RAM. I think that it's far superior as a sector-addressable optical disc format, but the discs are more expensive (you do get more for the price) and most DVD drives can't read them.
I think it's true that DVD+R[W] has a more robust method of storing information in the pregroove than DVD–R[W]. But that information is only used when burning the disc. It has no effect on the readability of a 10-year-old disc, but it might have an effect on its rewritability, I suppose. The user data is encoded in precisely the same way on pressed DVDs and DVD±R[W]. DVD+R[W] does not have better error correction for your data, just for the pregroove information.
When using rewritable DVDs as sector-based media with a filesystem like UDF, I think DVD+R has advantages over DVD–R because it's erasable in smaller blocks (?). If you're writing and erasing whole discs at once, there's no advantage.
The Wikipedia article is obviously a mess. I'm pretty sure that DVD+R doesn't have a smaller capacity than DVD–R by design. Capacity varies slightly between manufacturers, and some random person stuck a couple of random blank discs in their drive and put the reported capacities in the article. -- BenRG (talk) 00:13, 19 February 2011 (UTC)[reply]
To give more context, I'm only interested in data disks, for archiving. So I want something that will still have the data after ten or twenty years in a drawer, and which will be readable when put in most computer DVD drives. What is best for that? Thanks 92.29.119.194 (talk) 00:41, 19 February 2011 (UTC)[reply]
I recall DVD-RAM being better than DVD+RW but it's also way more expensive last time i checked. Read technology specifications to know for real. Anyway DVD+R is still better than DVD+RW due chemical stability. As for physical discs, Verbatim is likey the most reliable. And extremely vary of rip-offs etc.. very common these days! with products that have the logotype and look of the original but lack any quality. Infact make a software setup so that you can use the writer feature that measure the resulting margin which ends up on the discs. To improve storage you should eliminate the oxygen, humidity and heat. Nitrogen and humidity absorbing materials can be helpfull in this aspect. Electron9 (talk) 04:18, 19 February 2011 (UTC)[reply]
~~Is DVD-RAM readable by most computer DVD drives? Thanks 92.15.16.146 (talk) 11:07, 19 February 2011 (UTC)[reply]~~
~~Strange connectivity issue~~
When I use my router's ability to change its MAC address ('MAC address clone'), I lose my connection to the internet until I set it back to the old default address. However if I connect through a different router or even directly through my computer (all of which have different MACs), there doesn't seem to be a problem. WHy is this? 72.128.95.0 (talk) 20:15, 18 February 2011 (UTC)[reply]
I'm assuming you're using a cable internet provider? My guess is that the MAC address of your alternative router and your PC are also logged by your provider as legitimate addresses, but that the new address you change you router to isn't.--Phil Holmes (talk) 10:50, 19 February 2011 (UTC)[reply]
~~Long term data storage~~
Some what to do with the DVD question previously, If i took various kinds of data storage (CD's,DVD's, floppys, USB drive etc and any others ppl think off) put them in a box and left them at say standard room conditions. (So there not in perfect isolation but then there not being kicked around and left in the sun). Which would "hold on to" its contents for longer? ie if i came back in 10 years time and assuming i had kept the various drives/drivers etc, would any of them be expected to of had some of the data "disappear"?--86.145.90.102 (talk) 23:17, 18 February 2011 (UTC)[reply]
I beieve that if stored in room temperature in sealed cases I think the will work perfectly after ten years. Even more if you put it in a vacuum I would think. General Rommel (talk) 23:27, 18 February 2011 (UTC)[reply]
Have a look at the Library of Congress CD-R and DVD-R/RW longevity project, part of the Digital Media Preservation project. Disc coatings can peel and crack. In this thorough report, Longevity of CD Media - Research at the Library of Congress, quantitative failure rates are published. Nimur (talk) 23:34, 18 February 2011 (UTC)[reply]
Here's a similar question from the archives which has some interesting information 82.43.92.41 (talk) 00:01, 19 February 2011 (UTC)[reply]
For data that are actually high-value, you need not only media to store them on, but procedures for verifying them, copying them to new media, switching from older media to new ones (e.g. to maintain compatibility with new machines), and so on. Maintaining a long-term data archive will end up being not so much like keeping a bunch of books in a vault, but rather like running a scriptorium. --FOo (talk) 07:01, 19 February 2011 (UTC)[reply]
~~February 19~~
~~What do you do?~~
OK, computer experts. I am looking at my Windows 7 box right now as it displays a dialog box telling me my computer is low on memory and I should "Close programs to prevent information loss". The mouse cursor has disappeared, the keyboard does nothing, ctrl-alt-del doesn't display the Task Manager, and the computer appears unresponsive and inert ... except that the hard disk light on the tower flashes several times per second. The light is off, I'd estimate, 90% of the time in any given second, and the other 10% of a representative second, it's on (distributed throughout that second in a number of flashes, if I'm making sense.)
I've seen this phenomenon many times before on XP boxes, a few times on Vista boxes, and this is the first time on a Windows 7 box.
The question I put to you all is: What do you do when your machine locks up except that the hard disk light keeps flashing? Do you express faith in protected memory and the OS by waiting for an hour? Two hours? Begging for your mouse cursor to return? After all, maybe it's hitting the page file a lot and it's all fragmented, or something, and the computer will come to its senses any second now. Or do you swear explosively after sixty seconds of inactivity and cold boot the machine? Comet Tuttle (talk) 00:20, 19 February 2011 (UTC)[reply]
When I have a computer that misbehaves in any way, I usually format its boot partition and re-install a fresh copy of an operating system I trust on it. (This can include Windows XP, for some computers). Installing Windows XP usually takes around 15 minutes - faster than diagnosing and debugging any type of system corruption. (Customization and program-installation can take longer, but not "much"). For this strategy to be effective, you need to design your computing infrastructure such that catastrophic-loss-of-operating-system has minimal or zero impact on the integrity of your important data. You can accomplish this by robustly backing up important data, and/or placing data on separate disk partitions and separate physical media. Also note that this doesn't fix "broken" (or obsolete) hardware. Nimur (talk) 00:28, 19 February 2011 (UTC)[reply]
To answer the question directly, I cold-boot the machine, and then I contemplate the fact that I have been asking the machine to do more than it is capable of (because of its limited memory), and I think about whether it would be better to (a) reduce my demands, possibly by removing cruft that is running in the background (b) add more memory, or(c)get a new computer. Looie496 (talk) 06:17, 19 February 2011 (UTC)[reply]
~~How can my organization's editor, or I, do minor updates and corrections on your posted biography of me (Amory B. Lovins)?~~
Last year I tried to enter some necessary corrections, but didn't realize that any entries not frequently saved would be lost. so several hours' work were for naught, and nobody could help. Now the professional editor of my nonprofit employer, Rocky Mountain Institute, is trying it again, but his edits keep being promptly reverted, apparently by one Arthur Rubin, for unknown reasons. Cam just found in the edit history a cryptic message from "Johnfos" (http://en.wikipedia.org/wiki/User:Johnfos) saying "rv, none of that was very helpful," but we don't know what/who "rv" is, nor how to reach Arthur Rubin or Johnfos to ask their help and solicit their cooperation. We are trying hard to follow your standards and to make the bio more accurate and up-to-date, but we are finding this difficult and frustrating, doubtless due to our being newbies. Please email us what to do, since we are having trouble figuring out how to use your doubtless excellent, but for us complex and cryptic, system. If you'd rather we submit edits somehow to someone else to consider and (we hope) enter, just tell us how. Thank you very much. -- Amory B. Lovins (amory@rmi.org), editor Cameron Burns (cburns@rmi.org).208.45.129.136 (talk) 05:27, 19 February 2011 (UTC)[reply]
The material that camburns is adding is not encyclopedic, it is pure PR-speak. Wikipedia articles about a person are intended to be the same sort of articles that would appear in Encyclopedia Britannica, not the sort of thing that a personal agent would write. There are many ways to open a discussion. Each editor has a "talk" page -- for example Arthur Rubin has Talk:Arthur Rubin. But more appropriately, each article has a talk page too -- in this case Talk:Amory Lovins. I have no doubt that a message posted there will lead to a reasonable discussion -- although if the aim is to get the maximum amount of praise into the article (and that's what camburn's posts look like they are aiming at), the results might not end up being what you want. Regards, Looie496 (talk) 05:47, 19 February 2011 (UTC)[reply]
I think Looie496 meant to say "Each editor has a 'talk' page -- for example Arthur Rubin has User_talk:Arthur Rubin". The link provided was to the talk page of an article about a person called Arthur Rubin, and not to the talk page of the Wikipedia user Arthur Rubin. --NorwegianBlue^talk 09:55, 19 February 2011 (UTC)[reply]

"rv" means revert, it is one of the standard abbrevations in the edit summary. I've advised another user on editing their own article before, in this page. Terms like "…among the world’s leading innovators…" are peacock terms, unless you can provide a third-party reference that does describe you as such. You should provide references for all statements you make. However, even if these were provided, as Looie said, it does sound like standard-PR over-gushing, and is likely to be toned down by other users. CS Miller (talk) 06:08, 19 February 2011 (UTC)[reply]

There is a guideline against writing your autobiography on Wikipedia. The reasons are explained in Wikipedia:Autobiography. --NorwegianBlue^talk 10:12, 19 February 2011 (UTC)[reply]
Mr. Lovins, the best way to deal with this is to post to Talk:Amory Lovins saying that you are the subject of the article and saying what you think should be changed. It's usually not a problem to make simple error fixes (dates etc.) directly yourself, but directly making more substantial autobiographical changes are frowned upon for conflict-of-interest reasons. Please try to write any suggestions in a neutral tone that doesn't come across as self-promotion, as they will likely be better-received if you do that. Note: Arthur Rubin is a notable mathematician who is also a Wikipedia editor, so there are separate pages connected with him. Talk:Arthur Rubin is for development of the Wikipedia biography about him, while User talk:Arthur Rubin is the page you would use for contacting him about his Wikipedia activity. You might want to enroll an account yourself, so people will know who they are talking to. Regards, 71.141.88.54 (talk) 10:35, 19 February 2011 (UTC)[reply]
~~Glasses less 34~~
~~How does glasses less 3d works? I can't find an article. --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 08:01, 19 February 2011 (UTC)[reply]~~
~~There's autostereoscopy. 88.112.59.31 (talk) 08:26, 19 February 2011 (UTC)[reply]~~
~~The history of branch prediction~~
Wikipedia's article on branch predictors says that the IBM 7030 (of late 1950s vintage) did static prediction. I did some research, searching the web, books, and papers for any computer predating the 7030 that did any form of branch prediction. I could not find any. So my questions are: Was the 7030 the first computer to predict the outcome of branches? If the 7030 was the first computer to predict branches, then did the idea of predicting branches predate the 7030? Thanks in advance. Rilak (talk) 08:15, 19 February 2011 (UTC)[reply]
STRETCH was a stupendously aggressive design with many "firsts", not all of which worked. If you look at the references to the 7030 article, in particular the online book "Planning a Computer System - Project Stretch", you might be able to find more info about the branch predictor. 71.141.88.54 (talk) 10:50, 19 February 2011 (UTC)[reply]
~~where to find someone who is interested in making something new easily~~
I'm not an active programmer, but I know how a common protocol works, and by inserting two lines into the protocol, you could get a different, really interesting protocol. I'd like someone to do this for me, they can publish the results too, under their name. (They can keep maintaining the project, too, if they want,, which would add to their portfolio and might help them get jobs, etc). I just want use of the resulting protocol. (I've already checked with others, and my changes do work). How would I go about finding such a person? Anyone who knows C++ and can recompile an existing project with a few lines of changes in a few minutes, could do this whole thing in 20 minutes, and it's interesting and cool. Thanks. 109.128.192.218 (talk) 10:24, 19 February 2011 (UTC)[reply]
If it's that simple, why not describe it here. 71.141.88.54 (talk) 10:39, 19 February 2011 (UTC)[reply]
Because that won't get anyone to make it? You'll just say the same thing others said: "yeah, that would work and it's pretty cool." Maybe I should make a programming contest, where everyone has 20 minutes to do it, and whoever's I judge best gets a prize of $50 and the right to say they won the contest. Ironically, the same people who in this way would end up working for free (i.e. all but the winner), probbaly wouldn't do it for $50 outright - especially the most talented one, the one who wins. So, I can't use $50 to get a copy of my working protocol outright, but I can use it to get a BUNCH of different solutions, all working, and all but one of them made for me for free... Boggles the mind. 109.128.192.218 (talk) 10:51, 19 February 2011 (UTC)[reply]
$50 for 20 minutes is probably pretty attractive to student programmers or the like. You could post an ad on craigslist, or to some programming forum as you suggest. But, I agree that most programmers with any experience wouldn't participate in such a contest for an uncertain shot at the prize money. They'd only do it if they were guaranteed payment on completion of the task. The reason I suggested posting the idea here is so that programmers here could then tell whether the idea made sense. It's often easy to overestimate the usefulness or underestimate the difficulty of some programming idea, especially for a non-programmer. 71.141.88.54 (talk) 11:11, 19 February 2011 (UTC)[reply]
There's no question if it works. Why don't you email me at M8R-0489c01@mailinator.com (made just now for just this purpose, don't worry about spam) and I'll respond with 2 lines, then you can come here and post that you agree it works. I've had enough confirmation that it works, now I'd just like to have it done. 20 minutes. for anyone who can recompile an existing project with a few lines of changes in a few minutes. That's not me. 109.128.192.218 (talk) 11:17, 19 February 2011 (UTC)[reply]

Why are you being so secretive? Just post it here. Or anyway, say what protocol or project it is. 71.141.88.54 (talk) 11:19, 19 February 2011 (UTC)[reply]
~~The use of Eq in Haskell~~
What is the purpose/function of Eq in Haskell (i.e. what restrictions does it place)? For example, what arguments could be passed to a function of type f :: [a] -> a but not to a function of type f :: Eq a => [a] -> a ? Widener (talk) 10:32, 19 February 2011 (UTC)[reply]
The restriction goes in the other direction: Eq is a type class, which means it's a subset of the class of all available types. If you're familiar with Java, Haskell type classes are like Java interfaces. Types that belong to the Eq type class support an equality comparison operation. There is a good Wikibook about Haskell (b:Haskell) that explains all this. 71.141.88.54 (talk) 10:39, 19 February 2011 (UTC)[reply]
~~Restrict access to one port~~
Hello,
I have an area of my site which I only want to be accessed via a certain port that is rotated every week, for additional security. Is there any way that I can do this using a file on my server, say htaccess or something of that sort?--213.168.117.109 (talk) 11:25, 19 February 2011 (UTC)[reply]

@@ Line 808: / Line 808: @@
 What is the purpose/function of Eq in [[Haskell]] (i.e. what restrictions does it place)? For example, what arguments could be passed to a function of type f :: [a] -> a but not to a function of type f :: Eq a => [a] -> a ? [[User:Widener|Widener]] ([[User talk:Widener|talk]]) 10:32, 19 February 2011 (UTC)
 :The restriction goes in the other direction: Eq is a [[type class]], which means it's a subset of the class of all available types.  If you're familiar with Java, Haskell type classes are like Java interfaces.  Types that belong to the Eq type class support an equality comparison operation.  There is a good Wikibook about Haskell ([[b:Haskell]]) that explains all this.  [[Special:Contributions/71.141.88.54|71.141.88.54]] ([[User talk:71.141.88.54|talk]]) 10:39, 19 February 2011 (UTC)
+== Restrict access to one port ==
+Hello,
+I have an area of my site which I only want to be accessed via a certain port that is rotated every week, for additional security. Is there any way that I can do this using a file on my server, say htaccess or something of that sort?--[[Special:Contributions/213.168.117.109|213.168.117.109]] ([[User talk:213.168.117.109|talk]]) 11:25, 19 February 2011 (UTC)

Revision as of 11:25, 19 February 2011

February 10

djvu viewer

how to use ir sensors...

Similar question to my previous one - Adding Firefox add-ons by script (Linux)

Livescribe Pulse Smartpen

Huggle with Wine

Need a piece of software to help with statistical research on speedy deletions

Qualcomm BREW

MAC address

February 11

Apache Tomcat counters

Why do Alarm Clocks sometimes not ring?

nokia 1280 ringtone

sql in c

A heuristic autoplaying bot that can defeat Lone Wolf on Halo: Reach - Exists?

Changing a wiki logo

ReferencePreservingDataContract in WCF calls

Connecting keyboard + monitor to a smartphone

February 12

Change language of OpenProj?

AES-256 Encryption Parallellism

Objective C Pointers

What flavor for Puppy Linux?

3d or 3d?

Sporadic wireless connectivity

Multi-threaded Data Compression

Search engine that ignores robots.txt

February 13

QVOD player

Avoiding the double-plug cables with USB bus powered devices.

rsync question

Apple Mac

[JavaScript] Not a number

Vista - 'Read Only'

Severe Bluescreen problem - I may have to format and reload Windows 7

Svg vs GIF

Laptop

Google Maps

Forms on MS Word

Editing a .docx (MS Word) document that has fields

February 14

Two questions:

windows

Clear Screen C++

rm -rf / on Linux

Even the task manager wouldn't come up on Firefox

GPL and other Open Source licenses

iNAC managed access blocking of prison phone calls - how does it work, and is it the same as the suppression of cell phones at political protests?

iPhone 3GS with an old bootrom

The Art of computer programming

voice

February 15

Maximum Length of Petaflop-Year Crackable AES-128 Password

Replacing a processor

Vector in C++ and maths

Slow ADO Query over Access with VB6 over a LAN

sound from heal

NEW MOTHERBOARD

Get silverlight

When pdf files fail

February 16

Did IBM Watson take the lead tonight on Jeopardy! ?

Error while calculating Windows Experience Index in Windows 7

extract text from PDF

VuDroid

GPS

How does IBM's Watson choose the categories and dollar amounts on Jeopardy?

Thumbnail images in Windows Vista

Standby

February 17

Generic DVD/RW software for Win XP

How do I save an LUA file as an LUA file in Vista?

Drive size increases after copy then delete files

WYSIWYG Wiki Editor

Kaspersky Internet Security fouling up my devices

Graphics/visualization question: converting vector field samples into continuous streamlines

Valve holder tax

Crossword puzzle generators

Keyboard/start-up problem