Wikipedia:Reference desk/Computing: Difference between revisions
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I want create a structure in MS Excel that allows me to select a value from a table by "addressing" it with the value from a specific cell, just like a lookup table or, in other words, if I was dealing with a database, the SQL query I'd use would be like "SELECT x FROM y WHERE k = m", where "m" would be the value of the mentioned cell that changes dinamically according to some variables, "x" would be the column of the table "y" containing the value I want and "k" would be the value I want to test. Is that possible? <span style="font-size: smaller;" class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/213.13.148.4|213.13.148.4]] ([[User talk:213.13.148.4|talk]]) 09:26, 18 March 2009 (UTC)</span><!-- Template:UnsignedIP --> <!--Autosigned by SineBot--> |
I want create a structure in MS Excel that allows me to select a value from a table by "addressing" it with the value from a specific cell, just like a lookup table or, in other words, if I was dealing with a database, the SQL query I'd use would be like "SELECT x FROM y WHERE k = m", where "m" would be the value of the mentioned cell that changes dinamically according to some variables, "x" would be the column of the table "y" containing the value I want and "k" would be the value I want to test. Is that possible? <span style="font-size: smaller;" class="autosigned">—Preceding [[Wikipedia:Signatures|unsigned]] comment added by [[Special:Contributions/213.13.148.4|213.13.148.4]] ([[User talk:213.13.148.4|talk]]) 09:26, 18 March 2009 (UTC)</span><!-- Template:UnsignedIP --> <!--Autosigned by SineBot--> |
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:Have you tried using the 'if' command? Googlepeek [http://www.google.co.uk/search?hl=en&q=excel+if+help&btnG=Google+Search&meta= here]. '''<font color="SteelBlue">[[User:Lanfear%27s_Bane|Lanfear's Bane]]</font> | <font color="DimGray">[[User_talk:Lanfear%27s_Bane|t]]</font>''' 09:35, 18 March 2009 (UTC) |
Revision as of 09:35, 18 March 2009
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March 11
Skype problems
Please help my microphone wont work with Skype on my laptop but it works with the Skype on my other computer. Skype used to work with my old microphone and I didn't change the settings so I assumed its broken so I got a new one and it won't work either! The test call doesn't say its muted or any other error message but I can't hear the message playback at all. My laptop is a Compaq, I'm running Windows XP, I have Skype version 3.8.0.188 and I have a Logitech headset. Can anyone help please? --124.254.77.148 (talk) 03:42, 11 March 2009 (UTC)
- This is from the "blindingly obvious" department, of course, but have you ensured that your microphone's volume setting on the computer isn't turned way, way down? It wouldn't show up as muted then, but if it's turned down low enough, it won't pick anything up, either. -- Captain Disdain (talk) 08:50, 11 March 2009 (UTC)
- This happens to me once in a while. Go to the Control Panel and open Sounds and Audio Devices. Click on the Audio tab and ensure that your microphone is enabled for the Sound recording. Mostly like it has been replaced by another device. Regards, Bendono (talk) 14:18, 13 March 2009 (UTC)
Gnome Sort
Hello. Can someone tell me how the Gnome sort can have a best case performance of O(n)? Also, how do you find the average case complexity of such an algorithm?--202.88.229.115 (talk) 04:34, 11 March 2009 (UTC)
- Best case scenario is when everything is already sorted. It will check n-1 items, which is O(n). -- kainaw™ 04:38, 11 March 2009 (UTC)
- okay,thanks. so the average case is also o(n*n)?--202.88.229.115 (talk) 04:53, 11 March 2009 (UTC)
- It is, in my opinion, just insertion sort. Instead of a nested loop, they mess around with the list pointer. The average case for insertion sort is O(n2). So, gnome sort would be the same. -- kainaw™ 06:06, 11 March 2009 (UTC)
- Even the ultra-crappy bubble sort is O(n) in the best case. Best-case isn't usually very interesting. We're mostly interested in worst case (if we know nothing about the data and are in need of finishing within some known amount of time) - or average case (especially if we know something about our data - and if we'll be doing a lot of sorting so that the average is likely to be statistically correct).SteveBaker (talk) 00:52, 12 March 2009 (UTC)
/stalk for pidgin
On Chatzilla, you could type /stalk some phrase and it would stalk that phrase or user. If that phrase was said, you would get the notification as if your name had been mentioned. Now that I've switched to Pidgin, it seems there is no such function. Is there any add-on, extension, etc. that will add this feature? flaminglawyer 06:32, 11 March 2009 (UTC)
- I think this function is often called "highlight" or "hilight".... (but I don't think Pidgin has it. It's far from a real chat client (but is awesome for IMs.)) --grawity 21:05, 13 March 2009 (UTC)
PNG in PHP problem
Recently, I've been trying to teach myself PHP. I have a free domain at X10hosting.com where I am trying to make a PHP-based website. According to X10hosting, GD is already installed, but when I try something like:
<html>
<body>
<?php
$img=ImageCreate(300,300);
//Do stuff to the image...
ImagePNG($img,"images/test.png");
ImageDestroy($img);
?>
<img src="images/test.png" border=0>
</body>
</html>
it doesn't display anything at all. And it isn't just this particular example, it seems to be more specifically the "ImagePNG" statement, I have tried it in various ways but it doesn't seem to work. Thanks in advance, Jkasd 07:50, 11 March 2009 (UTC)
- Have you tried checking the return from ImagePNG? I suspect your problem might lie in the image paths—the path used by executing code is *rarely* the same as the URL. But a better approach (assuming you don't need the images after the users' requests) would be to have a php script create the image and send it directly to the browser. You can accomplish that using the same ImagePNG command, just drop the filepath (see example at php.net). You could then just pass the URL of this image-processing php file as the src of the img tag. Not only will it be faster for single-use images, but it also conveniently avoids the problems of cross-session corruption and temporary file removal. – 74 08:40, 11 March 2009 (UTC)
- Ok, I've tried that (I think). I've put something like: in a different html file. But it will just display the browser icon for an unreadable image. The image.php file is more like:
<img src="image.php">
- Ok, I've tried that (I think). I've put something like:
<?php
$img=ImageCreate(300,300);
//Do stuff to the image...
ImagePNG($img);
?>
- this time. Is that how you mean, or am I still doing something wrong? Jkasd 02:27, 12 March 2009 (UTC)
- Take a look at the "unreadable image" — it might be an error message. --98.217.14.211 (talk) 03:56, 12 March 2009 (UTC)
- The correct image header needs to be attached to the image. Here is the php.net example code:
<?php
$im = imagecreatefrompng("test.png");
header('Content-type: image/png');
imagepng($im);
imagedestroy($im);
?>
- Note the header "Content-type"; that's what tells a browser how to handle the byte-stream that follows. Essentially, you should be able to point your browser at image.php and see the image. – 74 08:14, 12 March 2009 (UTC)
Java programming - how do I do this...
Hi,
I am currently writing some code which runs a loop, and in each run of the loop it creates an object (CD, say) - but I want it to create a differently named object each time, by incorporating the loop number into the name. How do I do this? Here's roughly what my code looks like:
for(int q = 0; q < database.size(); q++) // where database is an ArrayList { CD myCD* = new CD(); //where * is, insert the varible q }
I want this loop to produce varibles myCD0, myCD1, myCD2 etc.
Anyone know how to do this? Or point me in the right direction?
Any help is much appreciated.
Thanks! —Preceding unsigned comment added by 81.156.58.73 (talk) 10:29, 11 March 2009 (UTC)
- Let me point you in another direction. The name of the variable is internal to your application and in itself is fairly meaningless. Thus, if it your intention to store a number with each instance of a CD for whatever reason, then you need to store that within the CD object itself. For example, you could define CD as such...
class CD
{
public CD(int number)
{
this.number = number;
}
public int GetNumber()
{
return number;
}
private int number;
}
- In your initial code, please recognize that all of your CD objects will go out of scope (ie, become inaccessible) immediately after each iteration of the loop. Finally, you could use it like...
public static void Foo()
{
// Suggest parameterizing this with a type
ArrayList database = // ...
// Need a place to store CDs
List<CD> cds = new ArrayList<CD>();
for(int q = 0; q < database.size(); q++)
{
// Create CD instance; store loop number.
CD myCD = new CD( q );
// Add CD to list.
cds.add(myCD);
}
// Test: Output the stored numbers for each CD
for (CD cd : cds)
{
System.out.println( cd.GetNumber() );
}
}
- Hope this helps. Regards, Bendono (talk) 11:02, 11 March 2009 (UTC)
- Note that in Java, it is very uncommon for a program to have variable names like cd0, cd1, cd2, cd3... If that is desired, you should (at a minimum) use an array like:
CD[] myCD = new CD[database.size()];
for(int q = 0; q < database.size(); q++)
{
myCD[q] = new CD();
}
- It is nearly what you asked for - just the addition of a [ and ]. -- kainaw™ 12:57, 11 March 2009 (UTC)
- Certainly a typo, but if not obvious to others you will need to remove the type CD preceding myCD[q] in the for loop. Bendono (talk) 14:24, 13 March 2009 (UTC)
- Correct - changed code. Luckily, that's a typo the compiler would complain about. -- kainaw™ 17:05, 13 March 2009 (UTC)
digital pen/stylus
Would this work on my HP Compaq 4400? I want a cheaper alternative to this, which the tablet originally came with. ~EdGl (talk) 15:42, 11 March 2009 (UTC)
- Since my laptop screen isn't touch-sensitive, I guess I need to use the pen that comes with the laptop :\ I can't find any for less than $40 though, which sucks. Guess I'm outta luck, huh? ~EdGl (talk) 19:42, 11 March 2009 (UTC)
- I'm afraid so. If your tablet using magnetic tracking you absolutely need a stylus specifically designed to work to work with that tablet. APL (talk) 13:20, 12 March 2009 (UTC)
Incorrect behaivour or mailicious code?
Moved from misc desk
Hi,
I'm using Internet Explorer version 6.0.2009.2180.xpsp_sp2_qfe.080814-1242. When i search on Eliot Ness and press go. I get a file download. This does not happen with other search word as e.g. apple. And not in FireFox. I dont know what the file is I did scan it with symantec antivirus but that found nothing.
Just tought that I should inform you of this. —Preceding unsigned comment added by 213.31.11.24 (talk) 15:02, 11 March 2009 (UTC)
- The problem is almost certainly at your end. There is no known behaviour in the wiki software that would allow a file to pop up when you are just searching for an article. --Richardrj talk email 15:26, 11 March 2009 (UTC)
Sync Evolution and Collanos
How can I synchronize Evolution (software) with Collanos? Is there any way of exporting Collanos' data and importing them into Evolution? Is there a general format for task data? Mr.K. (talk) 17:23, 11 March 2009 (UTC)
Finding the same text in two different files
I have this Boston_Celtics_all-time_roster, and this Los_Angeles_Lakers_all-time_roster. Now, how can I find players that played in BOTH teams (if there's such a player)? I'd need something like diff or cmp but I'm not sure. Thanks! --Taraborn (talk) 17:56, 11 March 2009 (UTC)
- I'm not on a unix machine, so I can't test this, but here's what you do: say you have two text-files, "players1.txt" and "players2.txt", concatenate them, sort them, and then look for duplicate lines (using uniq). So something like this:
cat players1.txt players2.txt | sort | uniq -d
- But as I said, I can't test it right now, but that would be a way to do it. 195.58.125.47 (talk) 18:38, 11 March 2009 (UTC)
- Thank you! --Taraborn (talk) 20:03, 11 March 2009 (UTC)
- What you should use is
join
. Assuming that bothplayers1.txt
andplayers2.txt
are sorted,
join players1.txt players2.txt
- will give you what you want. --173.49.15.165 (talk) 02:29, 12 March 2009 (UTC)
- What you want is comm. The problem with comm is that it requires both files to be sorted. So, sort both files (sort will do that easily). Then, use
comm -1 -2 boston.sort lakers.sort
. The -1 suppresses entries only in the first file. The -2 suppresses entries only in the second file. What is left is entries in both files. -- kainaw™ 03:37, 12 March 2009 (UTC)
Google Currency Converter to Only Two Decimal Places?
Is there anyway to get Google currency converter to display the result to only two decimal places, unlike the current way it's shown?
--91.104.49.185 (talk) 19:02, 11 March 2009 (UTC)
- I think you can set that in your preferences (if you have a Google account). I'll check it out and get back to you. — Ched ~ (yes?) 19:49, 11 March 2009 (UTC)
- hmmmm ... couldn't find anything in either basic preferences or the calculator. Maybe one of the links it provides with result would give you more the output you're looking for. Sorry — Ched ~ (yes?) 19:49, 11 March 2009 (UTC)
- An easy solution would be to use a bookmarklet: just create a new bookmark on your browser's toolbar with the name as "Currency" and for the location paste this in:
javascript:(function() { for (var i = 0, h2s = document.getElementsByTagName('H2'); i < h2s.length; i++) { var h2 = h2s[i]; if (h2.className == 'r') { h2.innerHTML = h2.innerHTML.replace(/( = \d+[.,]\d\d)\d+/, '$1') } }; void(0); })()
- Now when you are looking at the ugly decimals, just click on "Currency", and they'll vanish. Greasemonkey basically does the same thing, but spares you having to click anything, at the cost of some complexity in setup. --Sean 21:12, 11 March 2009 (UTC)
Speex audio from Adobe Flex / Flash Player 10 .flv via Red5 to .wav PCM?
I am having trouble converting a .flv audio-only file uploaded from Adobe Flex / Flash Player 10 to a Red5 server using the Speex voice coder:
http://livedocs.adobe.com/flex/3/langref/flash/media/Microphone.html
http://jira.red5.org/confluence/display/codecs/Speex+Codec (which references an "official patch" to ffmpeg at the end)
Questions:
1. How do I extract the audio track out of such a .flv file?
2. How do I convert it from Speex to .wav PCM?
Thanks. 69.228.87.198 (talk) 21:54, 11 March 2009 (UTC)
- This is resolved; I needed the speex-1.2rc1 tarball instead of the debian/ubuntu libspeech-dev package, which is too old to link up with current versions of ffmpeg's --enable-libspeex.
cd ~/src/speex-1.2rc1/ ./configure --prefix=/usr make; make install cd ../ffmpeg ./configure --enable-libspeex make; make install ffmpeg -i SpeexQ6R16Efalse.flv foo.wav
- ...worked. 69.228.87.198 (talk) 06:59, 12 March 2009 (UTC)
Access 2007 and autogenerated form fields
Hi, apologies if this is covered in the archives. My basic problem is that I don't know enough Access jargon to Google the answer, and the same goes for searching on Wikipedia.
I'm looking for a way to make Access 2007 create blank copies of a group of fields within a record, as soon as data is entered into any field of the original group. The idea is to use a database to track each action taken on different parts of a work project, and when details of an action are entered, to have the database automatically create blank fields for the next action. Ideally using a form to enter the details, with the form's target fields being autoupdated at the same time. Can this be done while keeping all the data within one record - actually, can it be done at all?
Love the refdesks btw - so far you guys have answered every dumb question I posted here, both as an IP and when logged in :-) — FIRE!in a crowded theatre... 22:02, 11 March 2009 (UTC)
- I was under the impression that Access already behaved in this manner (though I may be confusing it with one of its SQL siblings). When you create a new record, all the fields in the record should be created as well. You can set these fields to a default value, but I think the default default value is blank. When updating a record, new fields should *not* be created (they should already exist). You might try using some sort of status indicator to determine which actions have and have not been completed. – 74 08:26, 12 March 2009 (UTC)
iPhone and Blackberry
This may be a dumb question... can you surf the internet like you would on a normal computer on an iPhone or Blackberry? Alientraveller (talk) 22:37, 11 March 2009 (UTC)
- (ec):Yep! The method is quite awkward, in my opinion at least, and some pages don't display properly, but it is possible. Note: You would want a data plan from your service provider, otherwise it could get quite expensive. Thanks, Genius101Guestbook 22:53, 11 March 2009 (UTC)
- The browser on the iPhone (I've never used a Blackberry, so I don't know about them) is extremely good and uses topical zooming to display large pages on the small screen. THis is different from other small-screen targeted browsers, which either just had a small pagesize (which breaks pages that assume a given screen size) or which tried to do clever things to pages (which inevitably breaks lots of them). It's let down by the network connection - even on 3G it's frustrating to use because of the network speed. So really "yes" in theory, but you probably wouldn't want to do (for long) in practice. 87.115.143.223 (talk) 23:20, 11 March 2009 (UTC)
- So, to summarize, yes, you can "surf the internet", but no, it's not "like you would on a normal computer". StuRat (talk) 01:22, 12 March 2009 (UTC)
- To add more detail, yes and no. Right now the iphone safari doesn't support flash, so those page elements will unviewable. But the iphone safari browser is a huge improvement over the old internet explorer mobile (have not used a recent version). Also, many pages, especially google pages, will default to a iphone specific version that may limit some features but fit better on the screen, and with the navigation elements. Sometimes you can override these page versions, but that depends on the site you're visiting. The iphone does not replace a computer-based browser, but it can certainly fill in a lot of holes. If you have some specific page you're concerned about, or concern you're getting at, you should ask about it. Shadowjams (talk) 05:55, 12 March 2009 (UTC)
When does a MAC Address Change?
Would I be right in assuming that MAC Addresses only change if some hardware change (which hardware by the way?). Will my MAC Address be the same if I switch OS (XP -> Ubuntu)?
TIA. PrinzPH (talk) 22:51, 11 March 2009 (UTC)
- The MAC is generally encoded into the ethernet adapter. In times of yore it was fixed (either by pull-up resistors or jumpers) on the ethernet card. Now it's generally kept in non-volatile (flash memory, generally) storage alongside the ethernet firmware. That means that it won't change when you reboot your machine or boot to a different OS, even if you blank (or replace) the disk entirely. You can, however, change it yourself if you want (or need) to (although there's rarely much point) - on linux there's an option to do that in ifconfig (ifconfig eth0 hw ether ab:cd:ef:01:23); I don't know of a standard way to do the same in Windows. 87.115.143.223 (talk) 22:59, 11 March 2009 (UTC)
- Oh, I didn't answer the "which hardware" part of your question. On old machines there was a separate ethernet card (and you might still have a separate wireless ethernet card or USB adapter) - the MAC address belongs to that, so changing that would result in a new MAC. These days most machines have the ethernet adapter built into the motherboard, so you'd have to change motherboard to accidentally get a new MAC. 87.115.143.223 (talk) 23:10, 11 March 2009 (UTC)
Ahh thank you... I used to think that the MAC address somehow had something to do with being an identifier for your computer's current setup (what memory, hdd, etc)... Maybe I confused it with how windows recognizes your computer and if you change too many components it will refuse to boot (into windows)? PrinzPH (talk) 00:24, 12 March 2009 (UTC)
- Microsoft have, at least in the past, used the MAC as part of the algorithm to determine your Globally Unique Identifier; in addition Microsoft does use the MAC as part of the scheme for Windows Product Activation. So you're right. 87.115.143.223 (talk) 00:58, 12 March 2009 (UTC)
- We have instructions for changing your MAC address under different OSs in b:Changing Your MAC Address. If you have changed the MAC address in one OS but not the other, or changed them differently in different OSs, then your MAC address would indeed change when you switch operating systems. --76.167.241.45 (talk) 04:21, 12 March 2009 (UTC)
- What? How can a value that's stored in a chip on a card vary depending on what OS you've booted? 93.97.184.230 (talk) 09:15, 12 March 2009 (UTC)
- On startup, the ethernet card loads its default MAC from flash and stores this in RAM. It uses this value when generating ethernet frames. When it receives the "set your MAC" instruction (e.g. from ifconfig) it changes that RAM copy, but not the flash copy. So the change lasts only until the card is reset or powered off. For a change to be almost-permanent, in the way 76.167.241.45 suggests, you'd put that ifconfig line into the OS's startup scripts. That said, some cards do allow you to permanently change the MAC stored in the flash. Note that changing the MAC is not without risk; factory set MACs are guaranteed to be unique, but if you set your own you risk duplicating an existing MAC on your network (in practice that's almost impossible if you pick a truly random MAC, but quite likely if you idly decide just to change one digit). In that event your local switch with get utterly confused, and the resulting network anarchy will be extremely difficult to diagnose. 87.115.143.223 (talk) 12:52, 12 March 2009 (UTC)
March 12
Hibernation Mode
Is it bad for your PC to be always kept in hibernation mode, and never shut down ecxept only about once or twice in a month?? La Alquimista 06:36, 12 March 2009 (UTC)
- Bad as in likely to damage something? No. Bad as in potential instability and possible OS errors? Maybe. Basically, if you don't experience significant problems doing so then there's no real reason not to. – 74 08:17, 12 March 2009 (UTC)
- It will not harm anything directly by being in hibernation mode. But inevitable program errors can become increasingly problematic the longer a computer goes without restarting. These problems will be things like software/OS crashes, not physical computer damage. Also, in modern desktop OSes, programs that are assumed to be closed may continue to run or maintain pieces of themselves in RAM (memory, not to be confused with hard drive space), which may over time contribute to higher memory usage. You should also be aware that hibernation mode (opposed to "suspend" mode) writes data to your hard-drive, which means that anything you have open may be recorded on your hard-drive at one point or another.
- As a very general rule, perhaps you should consider fully shutting down your computer on a regular basis. Perhaps once a week (although you could go much longer or much shorter). Shadowjams (talk) 09:30, 12 March 2009 (UTC)
- Applications will not stay resident in memory unless they're supposed to stay resident in memory (ie., if I quit Firefox, it's gone), and even then there shouldn't be any higher memory usage over time unless it leaks memory or has some funky memory fragmentation issues. Something is wrong with your software if 'inevitable errors' pile up and cause issues over time, especially considering that you're essentially forced to reboot occasionally for updates regardless; if you're having issues like this, you should reevaluate what you've chosen to install. -- Consumed Crustacean (talk) 00:54, 13 March 2009 (UTC)
- You're absolutely right, programs shouldn't leave threads running, or leak memory, but this is a simple fact of life in any moderately complex OS. Particularly if this user's running a windows OS, these things happen. Even firefox will have issues from time-to-time. Telling a user to uninstall teh offending software is not a realistic option. Shadowjams (talk) 19:24, 13 March 2009 (UTC)
- No, it isn't a "simple fact of life in any moderately complex OS". Firefox will not even do that. At worst, Firefox suffers from memory fragmentation leading to a larger memory footprint than it ought to have. As soon as you close it, however, the OS frees all associated memory and the problem goes away. Uninstalling the offending software is absolutely the appropriate solution, unless it's a driver or something similar from their OEM. This isn't Windows 98, memory doesn't just disappear into the ether. -- Consumed Crustacean (talk) 03:03, 14 March 2009 (UTC)
- This is a silly digression, and I appreciate your restraint, but there have been historically, and perhaps still are, memory leaks in many well developed programs, even in firefox (which is generally very reliable). There is ample evidence here, here, for a past bug, here, for if the user's not actually closing firefox, and another past issue. Or, perhaps it's a browser plug-in. It's up to the user to decide whether or not an occasional reset is better than foregoing a useful program. Shadowjams (talk) 11:21, 15 March 2009 (UTC)
- I am well aware of issues with Firefox 2 (and 3 with crappy extensions). You must realize that a 'memory leak' does not mean the memory has vanished. It means that memory has been allocated for the program, the reference to that memory has been lost by the program (or at least no longer used), but the memory has not been deallocated. That deallocation is brought about by the OS when the process is terminated. Again, no need to reboot the system, only the application need be. The only time memory leaks are a system-wide issue is when something that isn't typically terminated, such as a system service, is leaking memory. And if that's happening, and it's not necessary for system operation (ie. something installed by the OEM), then it is appropriate it nix it. It's pretty rare these days, especially compared to performance and memory issues caused by malware. -- Consumed Crustacean (talk) 00:04, 18 March 2009 (UTC)
- Hibernation simply pages out everything and shuts down your computer. It's that simple. You can unplug your computer if you want, unlike with "sleep" which puts your computer in a low power state. The only problems that may occur are with programs that depend on time - timer programs? --wj32 t/c 10:01, 12 March 2009 (UTC)
- On my Dell M1330 laptop, with 2GB RAM, it takes longer both to go into and to restore from hibernation than it does to make a clean shutdown and restart. So I only hibernate if I have to power off the laptop while doing something I can't save. Your mileage may vary, but I imagine copying 2GB of data to and from the hard drive takes quite a while on any PC.
Also, hibernation can't keep a server session alive, so when you power on again you'll find yourself logged out of most websites you were using. Your data will be lost unless you copied it into a Notepad window before hibernating. — FIRE!in a crowded theatre... 18:42, 12 March 2009 (UTC)- Well no wonder my computer has been acting unusually slow lately. The only time I bother to turn off my computer is when it freezes and I have no choice but to restart it or if I click Turn Off Computer by accident. I'm glad I read this thread, because it's a question I've been pondering myself. --Whip it! Now whip it good! 21:19, 12 March 2009 (UTC)
- That should not be happening even on Windows unless you're using ME/9x. I never do a full shutdown or restart of my Windows box unless I've patched something and need to do so. No issues. You've probably got some crappy or malicious software installed. -- Consumed Crustacean (talk) 00:48, 13 March 2009 (UTC)
- Well no wonder my computer has been acting unusually slow lately. The only time I bother to turn off my computer is when it freezes and I have no choice but to restart it or if I click Turn Off Computer by accident. I'm glad I read this thread, because it's a question I've been pondering myself. --Whip it! Now whip it good! 21:19, 12 March 2009 (UTC)
- On my Dell M1330 laptop, with 2GB RAM, it takes longer both to go into and to restore from hibernation than it does to make a clean shutdown and restart. So I only hibernate if I have to power off the laptop while doing something I can't save. Your mileage may vary, but I imagine copying 2GB of data to and from the hard drive takes quite a while on any PC.
Extract the constant term from a polynomial, with Maple9
Hi, excuse this naive question. I'm doing a computation with Maple9. As a result I have a huge trigonometric polynomial, and I want to extract the constant term. As a mathematician, I would just integrate over [-pi, pi], but this can not be the right answer. How can I just make it find the constant term? Thanks --131.114.72.215 (talk) 14:15, 12 March 2009 (UTC)
- You might try asking at the math desk if you don't have any luck here. --Sean 17:59, 12 March 2009 (UTC)
Security Software
I just bought a new Dell Inspiron 1525 and it came with Trend Micro Internet Security and I have Windows Defender on it, too. Reason is that I have installed Stumble Upon and now I'm addicted. But I don't want to leave myself vulnerable. Is this enough security? I think I might be missing something. --Emyn ned (talk) 14:44, 12 March 2009 (UTC)
- Make sure that the internet gateway (DSL router, cable box, etc.) that you're using to access the internet (assuming you're doing so at home) has a firewall and that the firewall is enabled (with as few inbound ports open as possible; ideally none). If you're using a wireless connection to it, make sure the connection is secure (and uses WPA, not the earlier and much less secure kind). Have a spyware scanner (like Spybot Search and Destroy) and run it occasionally. Many people (myself included) will recommend that you use a browser other than Internet Explorer (such as firefox, safari, opera, or google chrome). If you do choose to run IE, adding the Yahoo! toolbar (which can catch some fishing and spyware sites) is a good idea. Always make sure your Windows Update is up to date, and that browser plugins (particularly Adobe Flash and Adobe Acrobat Reader) are up to date. 87.115.143.223 (talk) 15:42, 12 March 2009 (UTC)
yes, I use Firefox but I don't have any Spybot Search and Destroy. How do you know if I am using WPA? My landlord has the wireless connection set up and I am allowed to use it for free. --Emyn ned (talk) 15:48, 12 March 2009 (UTC)
- You can get SD&D via the Spybot - Search & Destroy article; it's very good (and free). If you double-click on the little icon that appears when you wirelessly connect, you should get a little box that gives some details of the wireless connection (I don't have a windows machine to hand right now to confirm). I think it says "secure connection" or "WPA secure connection" or something like that. If you didn't have to enter a security code the first time you connected to the wireless then the connection is "open", and thus unsecured. If that's the case you should talk to said landlord and suggest enabling WPA security - that way only people he approves can access his network (and not Joe Pederast across the street). 87.115.143.223 (talk) 15:55, 12 March 2009 (UTC)
finding pixel with RGB in visual basic or visual C++
is there some code in visual basic or in visual C++ with which i could find a pixel with a specific color values(red, green, blue) at a particular Y- coordinate or X- coordinate? please post that fully.--harish (talk) 15:42, 12 March 2009 (UTC)
- A pixel in what - in an image, on the screen, on a video? 87.115.143.223 (talk) 15:43, 12 March 2009 (UTC)
- In Java, the AWT Robot can do this, either by creating a BufferedImage of the screen (allowing you access to a "copy" of that screenshot), or by returning the current color of the pixel at the mouse-coordinate. The AWT Robot can get screen information from anywhere rendered by the operating system (not just in the Java application window(s)). There's probably an equivalent feature in .NET Framework or Visual C++. Nimur (talk) 17:01, 12 March 2009 (UTC)
- This article describes the WinAPI calls that capture the screen in VisualC++ (I guess they're also exposed to VB by the same names). 87.115.143.223 (talk) 17:22, 12 March 2009 (UTC)
- Sure, just use GetPixel and get a handle to the whole screen. (Replace with another HDC if you need something more specific.) Here is a quick sample:
#include <cstdlib>
#include <iostream>
#include <windows.h>
int main( int argc, char* argv[] )
{
if (argc != 3)
{
return EXIT_FAILURE;
}
int x = ::atoi( argv[0] );
int y = ::atoi( argv[1] );
HDC hdc = ::GetDC( 0 );
COLORREF color = ::GetPixel( hdc, x, y );
::ReleaseDC( 0, hdc );
BYTE red = GetRValue( color );
BYTE green = GetGValue( color );
BYTE blue = GetBValue( color );
std::cout << "Red: " << (unsigned int) red
<< ", Green: " << (unsigned int) green
<< ", Blue: " << (unsigned int) blue
<< std::endl;
return EXIT_SUCCESS;
}
- Regards, Bendono (talk) 18:01, 12 March 2009 (UTC)
Why does YouTube add black vertical black bars to my (windows movie maker) videos?
I create them is WMM and when their uploaded no less than two different types of bars. The one outer ones are YouTube and the inner ones are WMM... How can I avoid them both? --217.227.127.109 (talk) 19:02, 12 March 2009 (UTC)
- It sounds like you are not correctly setting the aspect ratio when you save the video. It also sounds like you are making this mistake twice, in both Windows Movie Maker and also during the upload step. What aspect ratio is the original video? Make sure you use that value all the way through the process. Nimur (talk) 19:08, 12 March 2009 (UTC)
it create them videos to convert to flash and that alters them s —Preceding unsigned comment added by 194.80.240.66 (talk) 13:07, 13 March 2009 (UTC)
Make sure you are either creating your videos with a 4:3 aspect ratio (most people make their videos with a resolution of 640x480 or 320x240, which is the size of old youtube videos), or a widescreen 1280x720 16:9 aspect ratio if you want to fill up the whole box. If you make a video in 4:3 you'll still get the black bars on the sides, but you shouldn't be getting two sets of black bars; that's because you didn't fill up the frame properly before you exported in movie maker. 210.254.117.186 (talk) 14:52, 15 March 2009 (UTC)
March 13
after burning a dvd-r
May the disc then be too hot for the drive to read? I think this is happening now...--Open24HrsMotorwayStop (talk) 00:05, 13 March 2009 (UTC)
- According to DVD recorder the write laser is no more powerful that 400 mW (some google searches I've done suggest that 200 to 250 mW is more normal). That's about 1/1000 th of the total power expenditure in your entire system. That seems much too low to raise the temperature to anything worth worrying about. 87.115.143.223 (talk) 00:27, 13 March 2009 (UTC)
- Ok thanks. I'll try it again.--Open24HrsMotorwayStop (talk) 00:45, 13 March 2009 (UTC)
- I do find that freshly burned dvd's are pretty warm. That's probably from the general amount of heat in the drive when it's burning, rather than directly from the laser. I haven't noticed unusual problems reading the discs immediately after burning. I do notice a significant rate of failed burns (whether caused by defective discs or what, I don't know) no matter what I do, both with cheap discs and expensive name-brand ones. 207.241.239.70 (talk) 00:57, 13 March 2009 (UTC)
What's really happening here?
My home computer system has a middle-aged Dell flatscreen monitor. Of late, it has been "color-shifting", for lack of a better or proper term; what I mean is the entire screen, not just areas or lines or pixels, shifts to a bluish tint, or pinkish, or something else. Usually this is sudden, not gradual; also, usually it is not permanent -- although it doesn't always revert to correct colors, sometimes it just changes tint. It is also not a flicker in the electrical sense.
Apart from telling me that my monitor has mere days (if not hours) to live, what's really happening here at the hardware level? Alternatively, since slapping the side of the computer case also causes this color shift (sometimes back to normal, sometimes not), perhaps the monitor is fine and it's a graphics card issue?
Thanks in advance to hardware gurus, --DaHorsesMouth (talk) 01:36, 13 March 2009 (UTC)
- Have you jiggled the video cable? -- Consumed Crustacean (talk) 01:49, 13 March 2009 (UTC)
- Definitely sounds like a loose connection at one end of the cable or the other. The fact that it changes when you whack the computer case suggests it's at that end...but maybe not. If not - then try to borrow a video cable from someone and try swapping out the cable...if that fixes it then buy a new cable. If THAT doesn't fix it then I'd want to try the monitor on another computer - again, it helps if you either have another PC or a friend who doesn't mind you trying it. If you find the monitor works OK on another computer then it pretty much must be the graphics card...but this is not the usual symptoms bad graphics gives you. So first suspect the cable - that's by far the most likely thing. SteveBaker (talk) 02:49, 13 March 2009 (UTC)
- It isn't necessarily the cable itself, but just it's connection to the computer and/or monitor. Is it loose ? Does it have screws to tighten it down ? Are they tightened fully ? StuRat (talk) 04:55, 13 March 2009 (UTC)
- I'd give it 90% odds that it's a bad/loose VGA cable. I've had that pink-tint thing happen before and it's always that. What's likely happening is that the signal on a particular RGB channel (or whatever color scheme the output uses) is dying, while the rest come through, hence, the tint to the screen. Another option might be something faulty in the monitor, and that'd also seem more likely with a CRT monitor rather than an LCD. I'd seriously doubt it was a software issue or an issue with the video card internals. Shadowjams (talk) 19:34, 13 March 2009 (UTC)
Gmail offline
Hello Wikipedia,
I've just downloaded Gmail offline but it doesn't seem to be doing what i thought it could. Whilst its great for when i lose my internet connection mid-session, when I'm just no connected, it doesn't load up (so i can't read old emails for example). Have i mis-understood what Gmail offline is supposed to do or is there a bug in the system somewhere? Thanks, 81.140.37.58 (talk) 10:45, 13 March 2009 (UTC)
- I don't know about Gmail offline but as Gmail supports IMAP you can easily set up any IMAP client, e.g. Thunderbird so that you can read your mail while offline Nil Einne (talk) 11:47, 13 March 2009 (UTC)
- To expand on that answer a little: With 'normal' email (using the IMAP protocol, for example - as Nil Einne explains) you can choose whether you'd like your mail to be downloaded onto your own computer, stored there and deleted from the server - or to have it remain on the server. If you choose the latter (as you evidently have) then when you disconnect from the web, you obviously can't read your email anymore because it's not stored on your computer! The trouble with going the other route is twofold:
- If you have more than one computer - you can't read mail that you downloaded onto computer A while you're using computer B!
- If you get a lot of junk mail, it all has to be downloaded onto your computer before you have a chance to delete it. If you have a slow connection, that's a bad thing...but I suppose it might also expose you to more risk from malware...I use Linux, so that's not something I know much about!
- Anyway - if you are using a web-based email client, then you don't have a choice. Because the email software is running on the server and displaying your email as a web page - then obviously, your mail remains on the server. But if you use an email client such as Thunderbird - you can set it up either way.
- SteveBaker (talk) 12:16, 13 March 2009 (UTC)
- To expand on that answer a little: With 'normal' email (using the IMAP protocol, for example - as Nil Einne explains) you can choose whether you'd like your mail to be downloaded onto your own computer, stored there and deleted from the server - or to have it remain on the server. If you choose the latter (as you evidently have) then when you disconnect from the web, you obviously can't read your email anymore because it's not stored on your computer! The trouble with going the other route is twofold:
- No, you haven't misunderstood; you should be able to do what you describe. The last message in this thread may help. If not - what browser are you using? When you activated offline Gmail it will have asked you if you want to place a shortcut to it in the start menu or desktop - if they're there, do they work? — Matt Eason (Talk • Contribs) 13:35, 13 March 2009 (UTC)
question
if a softwares works is there any real reason to get newer version if you'res works ok? —Preceding unsigned comment added by 194.80.240.66 (talk) 13:24, 13 March 2009 (UTC)
- It's always wise to keep up to date with security patches and revisions. For a whole new version (costing more money) then you only need to update when the new version has features you want (that the old one doesn't). But software vendors want you to update, and by means of Planned obsolescence (e.g. no more support, no support for modern platforms) will try to persuade you to upgrade. 87.115.143.223 (talk) 13:48, 13 March 2009 (UTC)
- I go with the old standby: "if it ain't broke, don't fix it". Thus, I don't update working software unless absolutely necessary, as it's more likely to introduce new problems than help in any way. This is especially true of companies I just don't trust, like Microsoft. They are likely to sneak something in like a digital rights management system which makes it impossible to do what you could with the old version, or a bomb which disables the software if they think it isn't registered. Even if they don't do any of this, new software is often bloated with silly, useless features which makes it run slowly and lock up my computer. StuRat (talk) 15:22, 13 March 2009 (UTC)
- You should be very careful saying things like that. Sure, if you like your version of Minesweeper, sure, go with that, but if we're talking things like web-browsers, servers, operating systems, Acrobat Reader, security software or anything that connects to the internet, it is imperative that you at least get the security updates. I'd say this especially applies to Microsoft, you have to have Windows Update running, you're a fool if you don't. When in doubt, update. Belisarius (talk) 23:50, 13 March 2009 (UTC)
- I'd say my same logic would apply to those programs, as well. Sure, they may patch some security holes, but they probably create just as many with each new patch. Otherwise, Windows has had so many patches that it would be completely impenetrable by now, wouldn't it ? And is it ? Heck no. StuRat (talk) 06:44, 14 March 2009 (UTC)
- It will have security holes ofcourse, but they are ones yet to be discovered, while continuing to use, say unpatched browsers or an operating system online is probably asking for trouble. I also don't think security updates to software necessarily creates new holes the same time it patches others; if it's an entirely new version of the software that includes new features, that's very possible. 76.117.247.55 (talk) 00:30, 15 March 2009 (UTC)
- No piece of software ever be 100% secure - what developers do is try to stay far enough ahead of potential attackers that its not worth their effort to mount the attack. As new exploits and attack technologies are developed, so 'secure' software has to be moved forward to take account of them. Once an exploit or attack mode is identified that needs a patch, there is a short grace period during which the mechanism of that attack is kept relatively secret until countermeasures are put in place in all affected products. Once the fixes and patches are published, usually so are details of the exploit that they prevent. Therefore it is important to apply all published updates as soon as possible - once they're out there, so are details of what they fix, and an unpatched machine can be a 'sitting duck'. A lot of the risk is related to the phrase 'not worth their effort' above - it is potentially much more useful to attack the software you use for internet banking or for collecting your work emails, than what you use to play Minesweeper. If the software publisher takes the opportunity of security patching to add less-than-wanted features such as the DRM or licence-validity checking mentioned above, it might be time to move over to a different supplier, such as FLOSS software, for example. --Nigelj (talk) 14:34, 19 March 2009 (UTC)
I need a boot disk
Can anyone recommend a free downloadable boot disk that will allow me to restore the master boot record for Windows XP? My MBR is currently trying to load from a boot loader that no longer exists (I forgot it was still being used and deleted it...), I need to get it to load from the standard XP boot loader (which I'm 99% sure is still where it should be and in working order!). Thanks. --Tango (talk) 13:41, 13 March 2009 (UTC)
- If you won't have a Windows CD already (fixmbr in the recovery console), you can do it with this Ubuntu recipe. 87.115.143.223 (talk) 13:44, 13 March 2009 (UTC)
- Yeah, unfortunately I left my Windows CD at home (I'm at uni at the moment). I don't have access to a CD burner (the only one I have is on the computer that doesn't work!) so it needs to be a bootable floppy. I've found shareware boot disks online that would do it, but it seems to need to pay about $20 to unlock the part of the program that actually writes the new boot record to disk. I'm wondering if anyone knows of a free one. --Tango (talk) 13:53, 13 March 2009 (UTC)
- Is a Pendrive Linux an option for you? 87.115.143.223 (talk) 14:10, 13 March 2009 (UTC)
- Unfortunately not - my computer doesn't seem to have an option to boot from USB. --Tango (talk) 14:12, 13 March 2009 (UTC)
- Is a Pendrive Linux an option for you? 87.115.143.223 (talk) 14:10, 13 March 2009 (UTC)
- Then try FreeDOS: fdisk /mbr FreeDOS doesn't support NTFS volumes, but I guess its fdisk command is smart enough to recognise one and fix the mbr accordingly. But you're into data-loss territory if I'm wrong. 87.115.143.223 (talk) 14:22, 13 March 2009 (UTC)
- Or TomsRTBT (same caveats as freedos) 87.115.143.223 (talk) 14:48, 13 March 2009 (UTC)
UBCD 4 Windows ? — Ched ~ (yes?) 14:37, 13 March 2009 (UTC)
- Unfortunately, I don't have access to a working CD burner, so I need a floppy disk version. --129.234.4.76 (talk) 14:41, 13 March 2009 (UTC)
- Which UBCD doesn't seem to have - http://www.ubcd4win.com/faq.htm#floppy 87.115.143.223 (talk) 14:42, 13 March 2009 (UTC)
- Missed that part: bootdisk.com would probably be your best hope then — Ched ~ (yes?) 15:00, 13 March 2009 (UTC)
- Which UBCD doesn't seem to have - http://www.ubcd4win.com/faq.htm#floppy 87.115.143.223 (talk) 14:42, 13 March 2009 (UTC)
A FreeDOS boot disk fixed the MBR, so thanks all of you for you help! However, it turns out the XP install isn't in working order after all, so I guess I'm now on a quest to find someone with a repair CD... --Tango (talk) 15:56, 13 March 2009 (UTC)
Linux and Torvalds original source code
I've been using Linux exclusively as a desktop OS since November 08. I was just wondering, what, if any, code is still in the kernel from Linus Torvalds original version that he started spitting out on a keyboard attached to a 386 in a cold apartment in Helsinki back in 1991? Not really a useful question, but I'm curious. I think it'd be neat if there were still tiny bits of code from all those years ago still surging through my CPU right now...63.245.144.68 (talk) 15:28, 13 March 2009 (UTC)
- I'm sure many of the POSIX standard header files are the same, since they have usually no reason to change. --Sean 16:31, 13 March 2009 (UTC)
- The POSIX standard headers are part of glibc, not part of the linux kernel (and so were mostly authored by Roland McGrath, and none by Linus). The kernel does contain a very minimal version of some of the C standard library for use by kernel code only (which bears only a passing resemblance to POSIX). We have some pretty good evidence that even that has been overhauled - witness modern Linus slagging off 1991 Linus's coding of the (apparently simple) ctypes.h here. 87.115.143.223 (talk) 17:05, 13 March 2009 (UTC)
- I don't know how much survives from his university days (I do know that the very first version he posted has been lost in time, the earliest version of the code is 0.02 I believe), but our article on Linus states that about 2% of the code in the current kernel was written by the man himself. That's pretty staggering, considering that the entire kernel is a little over 10 million lines. That's 200,000 lines of code. Isn't that cool! Belisarius (talk) 23:43, 13 March 2009 (UTC)
- 200kloc isn't that much - I write about 100kloc/year. What's somewhat remarkable is that he reads and checks every line of code that everyone else writes too. Pretty much nothing gets into the kernel without Linus checking it out first. SteveBaker (talk) 01:54, 14 March 2009 (UTC)
Google toolbar and Firefox 3.0.7
Folks, this has been annoying me for days and I just cannot figure it out. I recently upgraded to Firefox 3.0.7 from version 2.something. In v2 the Google toolbar was below the Yahoo toolbar, but in v3 the positions are swapped and I have been completely unable to figure out how to put them where I want them, Google on the bottom. Anyone know the magic for this, or is it an issues with v3 itself? Thanks in advance. – ukexpat (talk) 16:07, 13 March 2009 (UTC)
- An issue with v3? Heresy! ;) Right click near the awesome bar (the address bar) and click "Customise". Then just drag and drop. - Jarry1250 (t, c) 17:27, 13 March 2009 (UTC)
- That doesn't work for me. I can move individual buttons but not the whole toolbar. Your suggestion works for IE but not for FF, at least for me. – ukexpat (talk) 18:20, 13 March 2009 (UTC)
- Thank you! That worked and all is good in my Firefox world! – ukexpat (talk) 19:24, 13 March 2009 (UTC)
Xlib fullscreen window sample
Can you give me a link to a minimal program that creates a fullscreen x window? Something along the lines found here but complete (the code there doesn't work for me or I miserably fail copy-paste). --194.197.235.29 (talk) 16:39, 13 March 2009 (UTC)
- I've fused a nice Xlib tutorial with the code you describe, making the following (which works on my Ubuntu machine):
// code a fusion of:
// http://fixunix.com/xwindows/91585-how-make-xlib-based-window-full-screen.html
// and Ch. Tronche (http://tronche.lri.fr:8000/)'s xlib tutorial
#include <X11/Xlib.h>
#include <assert.h>
#include <unistd.h>
#include <string.h>
#define NIL (0)
// compile with:
// gcc -o foo foo.c -lX11
int main (){
Display *dpy = XOpenDisplay(NIL);
assert(dpy);
XEvent xev;
Atom wm_state = XInternAtom(dpy, "_NET_WM_STATE", False);
Atom fullscreen = XInternAtom(dpy, "_NET_WM_STATE_FULLSCREEN", False);
int blackColor = BlackPixel(dpy, DefaultScreen(dpy));
int whiteColor = WhitePixel(dpy, DefaultScreen(dpy));
Window w = XCreateSimpleWindow(dpy, DefaultRootWindow(dpy), 0, 0,
200, 100, 0, blackColor, blackColor);
memset(&xev, 0, sizeof(xev));
xev.type = ClientMessage;
xev.xclient.window = w;
xev.xclient.message_type = wm_state;
xev.xclient.format = 32;
xev.xclient.data.l[0] = 1;
xev.xclient.data.l[1] = fullscreen;
xev.xclient.data.l[2] = 0;
XSendEvent(dpy, DefaultRootWindow(dpy), False,
SubstructureNotifyMask, &xev);
XSelectInput(dpy, w, StructureNotifyMask);
XMapWindow(dpy, w);
GC gc = XCreateGC(dpy, w, 0, NIL);
XSetForeground(dpy, gc, whiteColor);
for(;;) { // wait for MapNotify
XEvent e;
XNextEvent(dpy, &e);
if (e.type == MapNotify)
break;
}
XDrawLine(dpy, w, gc, 10, 60, 180, 20);
XFlush(dpy);
sleep(10);
return 0;
}
- Thank you, works very well on my ubuntu machine too. --194.197.235.29 (talk) 18:32, 13 March 2009 (UTC)
How backwards compatible is Windows 7?
What's the earliest software I can run on Windows 7? Can I run software originally written for Windows 95? 3.1? --70.167.58.6 (talk) 17:30, 13 March 2009 (UTC)
- I think that almost all applications that could run on Windows Vista will also work with Windows 7. Simple applications for Windows 95 did work on Vista. --Andreas Rejbrand (talk) 18:12, 13 March 2009 (UTC)
- If you're installing the 32 bit version, you can theoretically run anything back to DOS (Although you may want to use DOSbox or similar). If you're running the 64 bit version, nothing earlier than Windows 95: NTVDM was suppressed in the 64 bit versions of Windows. 76.117.247.55 (talk) 00:26, 15 March 2009 (UTC)
Are stored procedures considered part of the data layer or data access layer?
In reference to business applications where you have data, data access, business and UI layers, are stored procedures considered part of the data layer or the data access layer? I used to think the data layer, but now that I think about it, stored procedures do access data. OTOH, stored procedures are physically located on the database server whereas a data acess layer can (and often is) located on separate machine. A Quest For Knowledge (talk) 17:44, 13 March 2009 (UTC)
How games use CPU cycles
In a typical video game, assuming the computer or console has video acceleration with a separate GPU, how do the CPU cycles break down between graphics, sound, AI and mechanics? NeonMerlin 20:07, 13 March 2009 (UTC)
- That is impossible to answer because you aren't providing any reasonable construct of a "typical game" by saying "typical". Do you mean a typical shooter? Do you mean a typical real-time wargame? Do you mean a typical platformer? Do you mean a typical puzzle game? Do you mean a typical computer chess game? There are far too many choices of "typical" to begin to narrow down an answer. -- kainaw™ 20:38, 13 March 2009 (UTC)
- Yeah. A game like Half Life 2 will spend relatively little effort on AI, because it only has to move a few actors over a pre-computed graph toward a single target. For something like Starcraft 2 they have to move hundreds of actors against a range of targets, and they have to rely more on dynamic pathing because all those actors get in one another's way and (ideally) are supposed to behave in concert and move in formation. 87.115.143.223 (talk) 21:14, 13 March 2009 (UTC)
- Everything really varies intensely, ESPECIALLY over genres. shooters and sports games are much more likely to have large complex physics engines, whereas RPGs (a la Final Fantasy, that is, not MMOs) will have a limited physics at best. An RPG like FF would probably use most of it's CPU cycles for graphics, mostly because i can't imagine it really uses many CPU cycles at all. Evan ¤ Seeds 21:22, 13 March 2009 (UTC)
- Yeah. A game like Half Life 2 will spend relatively little effort on AI, because it only has to move a few actors over a pre-computed graph toward a single target. For something like Starcraft 2 they have to move hundreds of actors against a range of targets, and they have to rely more on dynamic pathing because all those actors get in one another's way and (ideally) are supposed to behave in concert and move in formation. 87.115.143.223 (talk) 21:14, 13 March 2009 (UTC)
- Well, it is pretty widely variable - and what with multiple cores - sharing RAM bandwidth, GPU's doing things other than graphics using CUDA...it's difficult to ask what it even MEANS to express these things as percentages. On the whole, we try to push the graphics off onto a separate thread - and hope that on a modern PC, it'll get its' own CPU Core. (The project I'm working on right now will do exactly that - and coincidentally, separating the graphics thread from the rest is my job for the next week or two!) On Xbox360 and Playstation-3, the graphics will almost certainly be off on its own processor. So in a sense, graphics takes 100% of one CPU core. For the rest - it's much more variable from game to game. On the last game I worked on at Midway (which was essentially a 3rd person shooter), we were aiming for a 30Hz update rate - and seeing perhaps 30% of our 33 msec going on collision detection and physics, 20% on AI...then lots of teeny tiny hard-to-catagorize things taking up the rest. There is a big overhead when you split things up into separate threads where the separate processes have to interlock their access to various resources - and that can easily blow 20% of your time if you aren't super-careful. The time consumed by actual "Game mechanics" is usually completely negligable - and I guess audio might eat a few percent. If we can push physics and audio off onto their own threads - sharing another CPU, then we will. On Playstation-3, it's a lot more complicated because they have the "SPU" processors that are somewhere between the CPU and GPU of a 'classic' computer. Generally, they are such a pain in the ass to deal with (because they aren't like PC's and XBoxes and Wii's and anything else) that we'd use them for audio mixing and to offload graphics processing from the GPU - which is comparatively wimpy compared to the Xbox360 and modern PC's). I haven't worked on Wii. SteveBaker (talk) 00:37, 14 March 2009 (UTC)
- Tim Sweeney wrote an article about programming languages that has a breakdown of cpu usage in Gears of War.[1] (see slide 17). It is interesting. 75.62.6.87 (talk) 09:40, 16 March 2009 (UTC)
Partition problems lead to extremely slow computer
Ok, follow on from my question above: With your help, I got the MBR sorted out. I initially thought that something was wrong with the Windows XP installation and it wasn't loading, it turns out it was actually loading almost imperceptibly slowly, and continues to run at that speed once it has loaded. It takes 5 to 10 minutes from clicking on an icon to it becoming selected - that slowly! I am currently using it in Safe Mode (with networking), and it is running reasonably well. For some reason unknown to me, my C: drive reports a gigabyte extra free space is Safe Mode than in normal mode (That is, it reports 1GB rather than 10MB).
In case it helps, allow me to explain how I broke it in the first place: Some time ago I tried to set it up to dual boot with Linux, this failed due to hardware incompatibilities and I gave up on it. A partition for Linux was then left dormant on my hard drive (well, several actually). Recently my main Windows partition has been filling up and it got to the point where there was less than 10meg free and nothing more I could delete or move to a different drive/partition. I realised there was still this Linux partition there so tried to use Partition Magic to delete it and redistribute the free space between the other. It got half way through moving one of the other windows partitions up the drive when it failed due to an apparent bad sector and said no change had been made. This wasn't actually the case, it had already deleted the Linux partition(s). It was only when I rebooted that I realised the MBR was set to use GRUB on the Linux partition, which was now gone, but with your help I fixed that problem. I am now left with a slower computer than I have ever encountered and have no idea why. It may be to do with the drastic lack of hard drive space, but it got down to 500k just before I decided to try rearranging the partitions (I got it up to about 10meg first, but then ran out things to delete - most of the space it taken up by Windows itself). I could try and free up some more space while in Safe Mode, but it won't be easy... Is there a way to move programs from one drive to another without breaking everything (other than uninstalling and reinstalling - I don't have most of the install media with me)?
Any ideas what is wrong with my computer? Is it just the free space issue, or is there something else? Please help!!
--Tango (talk) 21:23, 13 March 2009 (UTC)
- Perhaps your swap file got damaged in all that process (it should just tell you and/or fix it itself)? 87.115.143.223 (talk) 21:38, 13 March 2009 (UTC)
- It hasn't told me any such thing. It can't have been doing much swapping before hand, anyway - I've had a gig of RAM and a few hundred meg of hard drive space for a while now (unless the swap file is somehow on a different partition than the one windows is on - is that possible? How would I find out?). --Tango (talk) 21:42, 13 March 2009 (UTC)
- The swap file is controlled in the system control panel plugin (I think there might be a "performance" or similar tab to go through). The control panel (or is it the administrative tools thing? I'm afraid I don't have windows to hand...) also has the system even log, which might have a slew of errors in it (from when things were running slow). 87.115.143.223 (talk) 21:52, 13 March 2009 (UTC)
- I couldn't find anything useful about swapping, but I found a system log that is full of errors about bad blocks - I will run scandisk (or whatever it is called in XP) and see if that helps. Thanks! --Tango (talk) 22:00, 13 March 2009 (UTC)
- God, Windows is annoying! It said it was "unable to complete the scan" but didn't think I might want to know what had gone wrong... So I've downloaded "Ariolic Disk Scanner" (it appeared about 6 times on the first page of a google search for "Windows XP disk scanner", so I thought it must be good!) and am running that now. No errors so far... --Tango (talk) 23:14, 13 March 2009 (UTC)
- I couldn't find anything useful about swapping, but I found a system log that is full of errors about bad blocks - I will run scandisk (or whatever it is called in XP) and see if that helps. Thanks! --Tango (talk) 22:00, 13 March 2009 (UTC)
- You said most of the remaining space is taken up by Windows. Since Windows has many optional components, you may want to delete some of the fluff until this problem is resolved. If you still have the install disks, it should be easy to add those Windows components back in later. Once you get some free space, try a defrag, as fragmentation is a problem when disk space is low. If you have a way to run Windows directly off a boot disk, that will allow you to do all these things at a reasonable speed, since you won't rely on Windows on the incredibly slow hard disk. StuRat (talk) 23:04, 13 March 2009 (UTC)
- That's not a bad idea. I'm currently typing this in Safe Mode, which is running at a decent speed, so I should be able to uninstall some windows components that I don't use from here. --Tango (talk) 23:14, 13 March 2009 (UTC)
- So much for that plan - the total size of all the optional components I have installed is 56MB, and only 20MB of that looked like something I could remove, and it wasn't entirely clear what was included with that component so I decided it wasn't worth removing it. I'm still baffled by why I seem to have a gigabyte extra free space in Safe Mode than normally... any ideas? --Tango (talk) 23:46, 13 March 2009 (UTC)
- The extra gigabyte could be swap space perhaps? Anyway, two ideas (if I recall correctly from above you say your disk now has some unpartitioned space): 1) If Partition Manager works in safe mode, run Partition Manager and increase the size of the partition. 2) If your CD burning software works in safe mode, download GParted, boot from CD and repartition from there. If this doesn't work and you still want to free up disk space, you can remove any free software you have installed, such as Firefox (if you use that) - you can just re-download these things after everything is fixed. Jørgen (talk) 02:39, 14 March 2009 (UTC)
- It was trying to do just that with the partitions that caused this mess in the first place! Unfortunately the partition with windows on it is at the beginning of the drive and the now unallocated space is at the end, which means I can't get more space in the main partition without moving the other partitions and that was what failed - apparently due to a bad sector in the unallocated space. I've managed to free up about 200meg (which has been enough for the last few weeks - I've been gradually deleting/moving more and more things as it fills up trying to keep it above 200meg, which is the point where Windows starts complaining), but it doesn't seem to have helped. If the extra gig is swap space then a) why doesn't Safe Mode need a swap file? and b) is there any way to tell it to use less swap space? I think the answer to my space problems is to buy a new hard drive, but I'm not convinced it is lack of space causing the problems (not directly, anyway). Thanks for your idea, though - any more? --Tango (talk) 13:50, 14 March 2009 (UTC)
- The extra gigabyte could be swap space perhaps? Anyway, two ideas (if I recall correctly from above you say your disk now has some unpartitioned space): 1) If Partition Manager works in safe mode, run Partition Manager and increase the size of the partition. 2) If your CD burning software works in safe mode, download GParted, boot from CD and repartition from there. If this doesn't work and you still want to free up disk space, you can remove any free software you have installed, such as Firefox (if you use that) - you can just re-download these things after everything is fixed. Jørgen (talk) 02:39, 14 March 2009 (UTC)
- So much for that plan - the total size of all the optional components I have installed is 56MB, and only 20MB of that looked like something I could remove, and it wasn't entirely clear what was included with that component so I decided it wasn't worth removing it. I'm still baffled by why I seem to have a gigabyte extra free space in Safe Mode than normally... any ideas? --Tango (talk) 23:46, 13 March 2009 (UTC)
- That's not a bad idea. I'm currently typing this in Safe Mode, which is running at a decent speed, so I should be able to uninstall some windows components that I don't use from here. --Tango (talk) 23:14, 13 March 2009 (UTC)
- Though I've never used XPLite, I suspect that it would be useful for junk removal. -- Hoary (talk) 05:35, 14 March 2009 (UTC)
- Your windows swapfile is called pagefile.sys, and is a hidden file in the root directory of your main drive. Instructions to delete it are here. In my experience bad things happen when you mix linux and windows partition managers. The fact that your computer's speed is ok in safe mode, makes me suspect that there may be a second problem, but I'd try to solve the disk problem first. Here's what I would do: (1) download and install the seagate disk wizard, (2) check that it runs properly in safe mode (it may give an error message if your current disk is not a seagate disk), (3) buy a Seagate disk, and boot the PC in safe mode with both disks connected. I'm not affiliated with Seagate in any way, but cloning disks with their program is really easy, I've used it a lot. (4) Clone your current windows partition and MBR to the new disk (letting it use all available space), and finally (5) remove the old disk and boot with the new one. If your current disk is not a Seagate disk, I'm not sure that this will work (I haven't tried), but I think the requirement for it to work is that you've got one Seagate disk connected. If, for some reason, this approach fails, I would use partimage (you'll need to download and burn a boot disk), make an image of the current windows partition on a usb disk, insert the new disk and restore the disk image to the new disk, making use of the entire disk. You will probably have to restore the MBR, but you know how to do that.
- If your computer still is slow when you've moved to a new disk, the reason has to be that one of the programs or drivers that are loaded in normal mode and not in safe mode, is causing the slowdown. --NorwegianBlue talk 15:15, 14 March 2009 (UTC)
Ok, I've freed up a couple of gig on C: by compressing old files (which I've always been reluctant to do since it feels rather like buying things on a credit card with no way of paying it off, but I saw little choice). I've also followed the instructions linked to above to move the pagefile from C: onto a completely different drive which has plenty of space. None of this seems to have solved the problem. If it helps, the computer only slows down after I try and log on - the welcome screen loads fine and it accepts my password fine, but then I get the "loading your personal settings" message which stays there for ages and then the desktop starts to load a bit at a time over the course of about 15-30 minutes, and then does virtually nothing - if I double-click and then wait another 30 minutes it might just about load My Computer. Any ideas? --Tango (talk) 16:48, 14 March 2009 (UTC)
Well, I seem to have things working now. I went through msconfig's selective startup options and gradually narrowed done which services were causing a problem. This took longer than expected because it seems there are two services independently causing everything to run really slow - KService (something to do with BBC iPlayer, I think) and MySQL. I can't work out why either of those would suddenly break just as I'm fiddling around with partitions, but I can do with them. Thanks everyone for your help! --Tango (talk) 21:20, 14 March 2009 (UTC)
Program
I couldn't think of a better title for this question: what I want is something where I would type in several words, for example, Fred, Cooper, and Smith, and it would spit out something like: FredCooperSmith, FredSmith, CooperSmith, FSmith, FCSmith, FCS, and so on. I was recently regestering some .tk websites, and was thinking that this would make things a lot easier. Thanks, Genius101Guestbook 21:54, 13 March 2009 (UTC)
- I just made you an application for this purpose: try FSCCalc.exe --Andreas Rejbrand (talk) 22:46, 13 March 2009 (UTC)
- Thank you very much! Genius101Guestbook 13:29, 14 March 2009 (UTC)
VNC client
Hi
Can someone suggest a good vnc client for windows, specifically one the may have a LAN browser, and tabs like Vinagre in ubuntu?
TIA PrinzPH (talk) 22:48, 13 March 2009 (UTC)
- Check out TightVNC and RealVNC. They are two of the more common varieties. Shadowjams (talk) 00:55, 14 March 2009 (UTC)
March 14
what is the best free antivirus program?
Are there any ones which are on all the time? So when I download a file it automatically scans it immediately?--75.187.113.105 (talk) 00:43, 14 March 2009 (UTC)
- There are three major free anti-viruses. They are:
- avast! Home Edition
- Avira AntiVir Free
- AVG Anti-Virus Free Edition
All three have resident/real-time protection against threats (That is, files are scanned upon opening and such). As for your second question, avast! has a Web Shield module which will scan almost everything (Certain content such as music files are excluded by default from Web Shield scanning to prevent slowdowns of your browsing speed) as they stream to your computer (Website content; avast! picks up a lot of malicious JavaScript) or as files download. (It creates a transparent proxy and redirects all web traffic through it to scan it for threats)
In personal tests that I conducted within a sandbox it successfully detected rogues (Fake software that bring along a lot of malware and that try to scan you out of your money) mid-download. With other threats it often detected them before I even got a download prompt! (Temporary files are scanned automatically and the threat(s) was/were detected)
avast! Home Edition (The free version) however lacks PUSH updates (Initiated by the avast! servers rather than by the user), a script scanner (Scans scripts executed on the local computer; more importantly though it scans websites in web browsers for malicious content), command-line scanner (used by those who prefer the efficiency of the command-line and those that wish to execute batch commands), automatic actions to be taken when a threat is detected (In the free version a popup appears with cool [But loud] siren sound effects showing the threat detected and giving the options available. In the Professional version; an action can be set to be taken automatically when a threat is detected), and finally the Enhanced-User Interface. (There are many complaints about the avast! Simple User Interface [I have no problems with it and love it for its simplicity] for looking too much like a media player etc)
However, avast! is the most fully-featured of the free anti-viruses with features such as the Boot-Time Scan (Scans your computer before Windows boots up to kill off threats before they can defend themselves against removal), the Virus Recovery Database (Stores copies of critical system files to allow easy repairs if they get infected), and the Virus Chest. (Same as the "Quarantine" area of most other anti-viruses but avast! allows you to scan files in it [As many times as you want] to check for false positives. In addition, you can add your own files to the chest. -- I recommend avast! but note that it lacks heuristics (Behavior analysis, this is regarded by some as just advertising though that creates too many false positives, making it difficult for the user to determine what is a threat and what isn't)
Avira AntiVir Free is also highly popular like avast! (Which has 75 million registered users+). In tests by independent companies such as AV Comparatives; it had the highest detection rates (But not for rootkits as discovered by other testers) beating out even GDATA which uses the BitDefender and avast! scanning engines for very high detection rates. Avira AntiVir Free though lacks anti-spyware and anti-adware; a major weakness. Like avast! it also prompts you for every threat detected (Can be annoying if you want to clean up a heavily infected machine). It has heuristics. -- I recommend it but be sure to use a good anti-spyware application alongside it and a good HIPS application as well.
Lastly, AVG Anti-Virus Free Edition 8.5. It is probably the most popular of the three.
I know this will cause controversy but I do not recommend it. The 7.5 version of AVG Free was excellent but the 8.x series lost too many features. No anti-rootkit is very bad as rootkits are becoming more common and ever more dangerous and difficult to remove. The reduced priority updates are also bad as AVG has usually had pretty bad detection rates for threats with old signatures. (Other anti-viruses can do rather well with out-of-date signatures but always keep them up-to-date. Even so, a recent study by Panda Labs shows that 35% of infected computers HAD an updated anti-virus. Having an anti-virus alone is not enough.) Its detection rate is describable as decent. If you want an AVG product, get the paid version not the free one.
If you are willing to spend a few bucks: (I suspect not as you asked for recommendations for free anti-viruses)
I most highly recommend the Kaspersky 2009 and Norton 2009 versions. (Yes, I know, "Norton sucks!"; yeah, well, not the 2009 versions, they are light and have demonstrated excellent anti-malware capabilities. However the following is true: "McAfee sucks!" :P)
Hope this helps. :) --Xp54321 (Hello! • Contribs) 02:54, 14 March 2009 (UTC)
Thank you very much. I installed avast and it works great. --75.187.113.105 (talk) 16:25, 15 March 2009 (UTC)
Firefox URL window doesn't work
And can Canon [?!] be to blame?
Here's an odd one. Yesterday, a Mac (Intel, 10.5.4) here had no printer attached but -- irrelevantly, I'd have thought -- Firefox, Safari and Opera all worked as expected. This morning, I plugged in a Canon laser printer and installed the necessary ("CAPT") software for this but haven't made any other change to the system that I can think of (and I've thought hard). Safari and Opera work just as they did yesterday. (And the printer works fine.) Firefox, however, now ignores anything I type in the little window at the top for the URL (or in the smaller Google window to its right). No error message, nothing: it's as if I hadn't made the final hit on the Enter key. However, if, still in Mozilla, I click anything within the "history", I can see it and go wherever I want from it by clicking links within it.
I upgraded Firefox from 3.0.6 to 3.0.7. No error message during (or after) installation, no difference after installation: I can go where I've been, and surf therefrom, but I can't specify a new URL or do a Google search.
The obvious solution is to ignore Firefox and use Safari and/or Opera, particularly as they are excellent and already installed. But as long as I don't know WtF's going on with Firefox, I worry that some other function of some other program will mysteriously crap out on me. Ideas? -- Hoary (talk) 04:35, 14 March 2009 (UTC)
PS I suppose that the scientific method (?) demands that I should experimentally uninstall the printer. But before taking that extreme (not!) measure, I thought I'd ask here. -- Hoary (talk) 05:30, 14 March 2009 (UTC)
- Hmm, that's very strange. There are a list of things to try with Firefox first, most of which are not so difficult. --98.217.14.211 (talk) 18:19, 14 March 2009 (UTC)
- Have you tried restarting the computer and reinstalling Firefox? Mac Davis (talk) 20:26, 14 March 2009 (UTC)
- Have you tried running Firefox in safe mode to check if an extension may be causing the problem, from Terminal run "/Applications/Firefox.app/Contents/MacOS/firefox -safe-mode". I believe old versions of the Delicious Bookmarks addon are known to cause a similar problems, so if you have that upgrade it or uninstall. JSK715 20:27, 14 March 2009 (UTC)
Best way to upgrade a Windows Millenium computer
This was my main computer but now sits on a shelf unused ;( as I had to get an ancient second-hand XP computer so that I could get broadband. It is an "etower 566cd" and has a 566mhz Intel Celeron Processor and I have installed 512MB of memory (the maximum possible) and a CDRW. It does not have an ethernet card though. It is a better machine that my ancient XP computer which has a pentium III and currently only 126MB of memory, although it does have an ethernet card. The ancient XP computer was upgraded from a lower Windows operating system before I got it, and the motherboard no longer seems supported, and the video card is probably defective too.
The two choices see to be a) Linux or b) upgrading to XP. I hestitate with Linux as my broadband provider does not support it, and I expect there is still far less freeware and other software for it. How much would an XP upgrade cost please? 89.241.151.22 (talk) 10:49, 14 March 2009 (UTC)
- I think it would cost more than Linux would; clearly, just how much you'd pay would depend on the nation in which you bought it, etc etc. My own broadband provider doesn't mention Linux either; but for all that company cares I could be using Plan 9. You'll find plenty of freeware for Linux, and all in all enough software to keep you busier with the machine than you are now with it. Hoary (talk) 11:29, 14 March 2009 (UTC)
- You don't mention how you plan to use the computer, but it sounds like you don't have specific, high-end (Windows-specific) applications in mind. For internet browser use, email, word processing, etc, you may find that machine will serve you best running Linux. I'm primarily an XP user, but I use Linux on a couple of older machines because it's so much less resource-intensive and there are excellent free distributions (e.g. Ubuntu ). In the past I did not recommend Linux to any but very sophisticated users, but it's gotten much easier to install and support. Also, Microsoft will end "mainstream" XP support this summer - another reason to consider Linux. --Scray (talk) 15:32, 14 March 2009 (UTC)
- One additional point: you can try Linux for free, and if you don't like it, switch to XP. You'll want to do a clean install anyway - leave no traces of Millenium! ;-) --Scray (talk) 15:33, 14 March 2009 (UTC)
Remote saving of pages
I'm looking for a way to remotely save a specified web page, such as a thread on a message board, updating it every 5 mins to ensure all new content is saved and stopping when the html source of the page has the following "<h2>404 - Not Found</h2>" (otherwise it will continue to save the page once the thread has died and the content has gone, saving only the error message). What would be the best way to accomplish this? The system would also need an interface where multiple people via the internet could specify the urls to be saved. —Preceding unsigned comment added by Cally012 (talk • contribs) 12:45, 14 March 2009 (UTC)
- Well, on a Linux or MacOSX box - you could write a shell script to run 'wget' in a loop with a suitable 'sleep' to delay saving. 'wget' grabs a page via HTTP and saves it. Under Windows - I don't know any simple way. You could install the 'Cygwin' suite - which includes the 'bash' shell and the 'wget' program. Stopping when you get a '404' requires a loop and a test of the exit status of wget...so, depending on what in detail you want to do...
- while ( wget http://sjbaker.org/wibble.html ) ; do mv wibble.html safe.html ; sleep 300 ; done
- This will take a snapshot of that page every 300 seconds - saving the latest version in 'safe.html' and exit automatically when there is an error (such as if page is 'not found'...ie a 404 error).
- But Cygwin is probably not the only way to do this - if you are familiar with Windows' god-awful native scripting system and can find a program like 'wget' that grabs pages off the Internet. SteveBaker (talk) 01:44, 15 March 2009 (UTC)
- Is there no online service that does this? —Preceding unsigned comment added by Cally012 (talk • contribs) 16:24, 15 March 2009 (UTC)
- You are asking for something really rather specialised - it's not something a whole lot of people need (or it would already exist in your browser or something) - so I'd be quite surprised it there was any off-the-shelf way to do this. SteveBaker (talk) 02:54, 18 March 2009 (UTC)
- Is there no online service that does this? —Preceding unsigned comment added by Cally012 (talk • contribs) 16:24, 15 March 2009 (UTC)
Xubuntu Loading Problems...
Hi,
I have a very slow laptop (256 Mb RAM, 1.5 GHz Celeron M Processor). I heard about this lightweight operating system, Xubuntu. So, I downloaded it from the official site, wrote the image on a CD. When I tried to install Xubuntu by booting from the CD, I went through a couple of menu and then some Desktop Environment came up and it promply hung there. It didnt even take me through all the process of allocationg space in a partition and everything. I even tried to Install it as an Application from Windows, the installation went well. But, when I tried to get in Xubuntu from the boot menu, it hung up at the desktop sceen. And in the desktop theres an bar of discoloration or a multi-colored bar just aboce the main taskbar on the bottom. Can someone please tell me what went wrong?
Thanks! Jayant,20 Years, India • contribs 14:09, 14 March 2009 (UTC)
- Are there options for "minimal" or similar at boot time? When I was installing a copy of Linux onto a laptop, I HAD to specify that or it would just die. 76.117.247.55 (talk) 00:22, 15 March 2009 (UTC) PS. Anyone know how to view a bootlog on that flavor?
- Nope, there weren't any options at all. I even "checked the CD for defects". But it didnt find any. During installation at boot time, it didnt ask me for any options regarding setting and all, it directly went to the desktop where it subsequently hung without showing me any options. Even when I select to work on a Demo of Xubuntu (Live CD) and install from there, the same thing happens (desktop hangs up). I have installed Linux before but never encountered any problems. This is very irritating as I really need to work on an unix environment for college practicals. Jayant,20 Years, India • contribs 09:41, 15 March 2009 (UTC)
- If you are having trouble using the regular Ubuntu installation CDs (this includes the variants such as Kubuntu, Xubuntu and so on), you can always try using the "alternate" installation CD for the same variant. It isn't quite as easy to install but it will install (and be usable) on a wider range of hardware. Other than that, you may want to try asking on the Ubuntu forums at ubuntuforums.org. Generally speaking, multicolored bars or blocks and other graphics anomalies are usually indicative of an issue with either the graphics card or (normally on really old systems) unsupported resolutions, and since I assume you have no such problems in Windows, my first guess would be that Ubuntu is trying to run at a resolution that your system cannot handle. If that is the problem, the alternate installation CD will help you get around it since it prompts you for the desired screen resolution during installation, and does so in text mode, which any PC supports. Have the laptop's manual available and just tell it to use whatever the screen's designed resolution is, and it should work. --Mkjo (talk) 13:58, 15 March 2009 (UTC)
- I installed it using the alternate CD.. It went off without a glitch. But Xubuntu is really really slow. Opening windowns and installing packages is taking a very long time. Firefox takes 2 minutes to open! Anyways, Thanks a lot for your replies. Cheers! Jayant,20 Years, India • contribs 20:40, 17 March 2009 (UTC)
Windows XP question
- Would someone here explain to me please how I can set up my PC to ALWAYS open new windows in a maximised state? For some inexplicable reason every window I open does so in a minimised state and I can't figure out how to reverse that. Thanks 92.20.139.55 (talk) 15:19, 14 March 2009 (UTC)
I'm not on one of my XP computers at the moment, but I think it's in your Folder options, on the advanced tab. — Ched ~ (yes?) 18:03, 14 March 2009 (UTC)
- Resize the folder the way you want it, then go Tools -> Folder Options, go to the View tab and click "Apply to All Folders" JSK715 20:02, 14 March 2009 (UTC)
printer beeping
A few months ago I hooked up an old laser printer to a new computer and although it worked fine for a while it kept making a very loud beep. After a few weeks it started overprinting within a small area of the page, so I threw it out and bought a brand new printer (Samsung ML 2850D). This prints just fine, but it keeps making the same loud beep when it is switched on and then every minute or so. The only way to stop it is to turn it off. I have been able to find nothing about this problem in the manual or the on-line forums. Any ideas?--Shantavira|feed me 17:00, 14 March 2009 (UTC)
- Does the beep come from the printer itself, or the computer's speakers? Thanks, Genius101Guestbook 19:07, 14 March 2009 (UTC)
- Hmm, even though the PC is on one side of my desk and the printer on the other, it's surprisingly difficult to tell exactly where the beep comes from. Although the speakers are turned off, I believe the PC has some sort of internal beeper? Anyway I turned the printer on and off a few times trying to get it to beep and it no longer seems to be doing it, despite having been doing it for some weeks......--Shantavira|feed me 19:48, 14 March 2009 (UTC)
- Yes, most computers can make some annoying beeps internally, and high frequency sounds are notoriously difficult to locate (key finders have this problem). If you have an extra child handy, you might ask them, as they have better high frequency hearing. StuRat (talk) 03:53, 15 March 2009 (UTC)
Memory upgrade for a Dell
I'm used to working on a Mac and have, on occasion, pulled the back off and stuck my head inside to replace RAM or a hard drive. But the 'family computer' in the kitchen is a PC. A Dell Dimension 1100, and I've never really poked around with that at all. I'm wanting to fit more RAM in it as it's only got 512mb and was wondering if it's as simple a job as it sounds. Do I just get some thing like this and unscrew the back, pull out the old RAM and slot the new one in? —Preceding unsigned comment added by 91.111.85.208 (talk) 19:00, 14 March 2009 (UTC)
- Generally, it easy to upgrade the RAM on a PC. First, however, you must make sure that you buy the right RAM module for your motherboard. After that you only need to push the new modules into their slots on the motherboard. Some cheap no-name computers look very messy inside, with a lot of wiring and small margins, but my experience is that Dell PC's are very easy to work with. Simply push the new module(s) into its/their slot(s). --Andreas Rejbrand (talk) 19:42, 14 March 2009 (UTC)
- When you bring in new RAM, make sure it is of equal or greater clock speed than your slots allow, and make sure it is the right kind of RAM. For example, if your previous RAM was 266 MHz DDR, make sure your new RAM is DDR and of equal or greater speed. If the RAM is of greater speed but your motherboard can't use it, then it will be downclocked and the RAM will be 266 MHz. Dells are very easy on the inside. Mac Davis (talk) 20:24, 14 March 2009 (UTC)
OK thanks. When I get in there, should it be written on the RAM what speed it is and if it's DDR?91.111.85.208 (talk) 23:28, 14 March 2009 (UTC)
- It might be easier for you to Google the motherboard to get its specs; the RAM itself will definitely tell you its capacity and whether it is DDR/DDR2/DDR3, but I doubt it would list the clockspeed. Useight (talk) 00:37, 15 March 2009 (UTC)
Burning dvd's &cd's
I am somewhat alittle computer illiterate,and thats why I have someone else building me a computer . I rec.'d an E-mail from this person last night , stating that I would'nt be able to burn a dvd nor a cd without first installing a graphics card ...((I havent made my mind up as to how much I want to spend on a graphics card yet)) I was under the impression that a graphics card ONLY has to do with replaying the graphics , by which , the onboard graphics of replay could be handled by the mother boards graphics for that.. Is he right in telling me I need to FIRST , install a graphics card to be able to burn DVD's or CD's? Like I said befor, I thought it was the software , not the graphics card, that you use to burn with.. It has a new DVD/CD burner in it(just installed)..Thanks ahead of time for your help, it is all deeply appreciated.. —Preceding unsigned comment added by 98.28.42.61 (talk) 19:01, 14 March 2009 (UTC)
- You do not need any particular graphics card in order to burn a optical disc (CD, DVD, Blue-ray disc etc.). (Of course you need some (very simple, perhaps on-board) graphics processing just to start Windows, but that's obvious.) However, if you for instance want to edit the movie clips on a DVD or Blue-ray, then, depending on your software, a good graphics card might be valuable. --Andreas Rejbrand (talk) 19:34, 14 March 2009 (UTC)
- I presume you're using the on-board graphics processor on the mother-board? If so - then this guy is telling you lies...probably in an effort to get you to buy a graphics card from him rather than going elsewhere. If you LITERALLY have no graphics output - then Windows won't boot and you'll have a hard time doing anything! However, even with no graphics of any description - you could still boot Linux - log into the machine remotely via the network (assuming it's set up to allow that) and burn CD's and DVD's without problems. SteveBaker (talk) 01:09, 15 March 2009 (UTC)
March 15
Cocoa Finder in 10.6
The page on 10.6 makes a note that the Finder for this version will be done in "Cocoa" instead of "Carbon", but the pages on Cocoa and Carbon don't seem to really explain why would be done or what good it would do. Is there any reason someone familiar with the APIs could explain? Thanx, 76.117.247.55 (talk) 00:18, 15 March 2009 (UTC)
- My best guess answer: 64-bit compatibility (as one of many other contributing factors). Carbon is not fully compatible with 64-bit programs under Mac OS 10.5. See also Google: cocoa vs carbon. LobStoR (talk) 05:02, 15 March 2009 (UTC)
- Lacking a single "right" answer (Which I suspect this question doesn't have), that's perfect. Thanx, 76.117.247.55 (talk) 03:09, 16 March 2009 (UTC)
Graphics cards
Question: Are 2x GeForce GTX 260's in 2-way SLI faster than 3x GeForce 9800 GTX+ in 3-way SLI?
(assuming the games support SLI)
Thanks for your time! ZX81 talk 01:21, 15 March 2009 (UTC)
- That's a lot of text... You may want to begin or end with your question, to make it easier to find (rather than bury it in the middle). That being said, I assume your question is: "Are 2x GTX 260's faster than 3x 9800GTX+?"
- Here's an article at Tom's Hardware comparing 3x GTX260s and 2x GTX280s. The answer to your question depends on whether or not the programs you plan to use will benefit from that type of SLI setup... If you are using this setup to play games, note that not all games will receive a benefit that scales linearly to the number of graphics cards you have.
- Another note... setups with NVIDIA SLI and multiple monitors may be more complicated than you think... you might not be able to simply plug in any monitor to any video card while SLI is enabled... check out this Google search for more information.
- LobStoR (talk) 04:45, 15 March 2009 (UTC)
- Yes that was the question. Too often we see questions on the reference desks not giving enough information and more questions needed answering first so I wanted to try and give as much as possible, but I went a bit overboard - Sorry! I've drastically shortened it now.
- Thank you for the links, especially the SLI and multiple monitors which took me to NVIDIA's SLI Multi-Monitor Support page which shows what I'm trying to do with the 3 monitors isn't even possible whilst it's in SLI mode. The question about the graphics cards is still valid though as the newer drivers now support 2 monitors so I may just have to use that instead of 3. Thanks! ZX81 talk 13:16, 15 March 2009 (UTC)
- This kind of question is VERY tough to answer - it's so dependant on the nature of the game and where it's bottlenecks are. SLI improves pixel throughput - but it makes geometry performance worse - so adding a third card (if that's even possible) will improve pixel rates - but not geometry. If you use your three screens to get the same field-of-view and just push up the resolution - you get a different answer than if you widen your field of view and keep the same resolution. It's really not the kind of thing where a definitive answer is possible. I'd stick with two cards - simply because that's what most game-writers develop with - and the most that routine play-testing happens with. Hence you're less likely to run into odd bugs due to inadequate testing of games and drivers in three-way mode.
Thanks for the responses and because it turned out I can't run 3 monitors on an SLI config I've decided to stretch my budget a little further to buy a single GTX 295 to drive the main 24" monitor and an additional GTS 260 for the 2x 19" ones. Thanks again! ZX81 talk 16:33, 15 March 2009 (UTC)
DVD video creation
I'm looking to burn a movie to a DVD so it can be playable in a standard DVD player. However, I don't know what the steps are to do this. Is there any instructions for software that can do this on Mac? --12.146.80.2 (talk) 01:30, 15 March 2009 (UTC)
- Oh, sorry for not having iDVD installed!--12.146.80.2 (talk) 13:52, 15 March 2009 (UTC)
- The easiest way (in the sense that most Macs have the program, not that the program is easy to use) is to use iDVD. Googling "burn DVD without iDVD" turned up this option that seemed like it might work as well for your purposes. --98.217.14.211 (talk) 15:18, 15 March 2009 (UTC)
You might like to look at Toast. They also sell one called Popcorn which is cheaper. Often when you buy a burner they come with DVD burning software, like these. I'm assuming that if you haven't got iDVD then maybe your Mac is a bit old and hasn't got a built in burner?91.111.85.208 (talk) 20:00, 15 March 2009 (UTC)
I'm spacing out on this Q...
I've noticed that the total size of the files on a standard commercial DVD isn't any less if the DVD contains a black and white movie (gray-scale, technically), than a color movie of the same length. Why is this, do they include more detail to take up the space which would otherwise be occupied by color info ? StuRat (talk) 03:43, 15 March 2009 (UTC)
- My guess is that the recording speed (and reading) of a DVD is constant in time. This is just a guess - will be interested in answers from those "in the know". --Scray (talk) 04:24, 15 March 2009 (UTC)
- Short answer: DVDs are always encoded with color. For more information, I would recommend that you read about the MPEG-2 codec - which is used on DVDs. Also, I recommend using a more useful section title than "I'm spacing out on this Q..." LobStoR (talk) 04:51, 15 March 2009 (UTC)
- So, to help visualize this, it's like they have RGB codes for every pixel, even when the 3 values are identical in every case ? You'd think someone would have fixed this by having an instruction in the header that means "this is a gray-scale file, so only one value is given for each pixel, which represents the Red, Green, and Blue values for that pixel". It seems like such a simple thing, and would allows 3 times as many black and white episodes to fit on a single DVD. StuRat (talk) 05:21, 15 March 2009 (UTC)
- It is possible to reduce certain video formats to grayscale and thus save a lot of space, but I think that Scray may be partly right in that this is a spin issue. A DVD player might not be as effective at buffering a disk with data compressed three times more than usual, or it might just be a precaution, or even just a marketing decision. Perhaps the King of DVD is under the impression that episodes of the Brady Bunch would produce more revenue if sold in sets of five instead of thirty. 210.254.117.186 (talk) 14:38, 15 March 2009 (UTC)
- (ec) Actually - it would make very little difference. Firstly, color information is stored at much lower resolution than intensity (they don't use RGB exactly) so color takes up maybe a quarter the space of the intensity data. Secondly, the compression routines are optimized to preserve intensity information at the price of color - so the savings would be MUCH less than 3:1...maybe 10% at most. But, you might argue, even 10% is worth having. But that's not all there is to it. The people who set these standards have to consider keeping software and hardware complexity to a minimum - over the course of the lifespan of the DVD standard, decoders for the format have to be implemented by many companies over many platforms and adding complexity where the benefit is small is a really bad idea. SteveBaker (talk) 14:39, 15 March 2009 (UTC)
32-bit memory limits and GPUs
I know that a 32-bit computer can only use 3.3-ish GB RAM, but does the same limit apply to graphics memory as well? 144.138.21.184 (talk) 05:16, 15 March 2009 (UTC)Will
- The absolute limit to the address space for a 32 bit computer is 4Gb (thats 2^32). Into that 4Gb of space the systems memory manager must map various things - most obviously is your RAM chips, but there's also the PCI address space and various other bits of hardware. That's where the roughly 3.3 Gb limit comes from (although that can, to an extent, be dodged with Physical Address Extension). Now when you say "graphics memory" we need to discuss what that really is. First let's assume you have a nice video card like an Nvidia (not a cheap solution like onboard intel, or a unified memory architecture like an Xbox). That card has its own RAM chips, which are visible to its own CPU (a video card really is a powerful independent computer, not a mere dumb peripheral). PCI devices can choose to reserve a chunk of the host system's address space for themselves - so if the host accesses that chunk of memory then the memory controller issues a memory-read or memory-write over the PCI bus (rather than over the DRAM bus) and that operation is serviced by the PCI peripheral that has claimed that chunk. PCI devices can choose to map all of their memory in this way (so it's just a 1:1 mapping) or they can choose to map only part of it. If the choose to map all of it, that all takes away from the 4Gb available for other things. Mapping all the memory makes life easy (mostly) for the author of the device driver, as he can just manipulate the inside of the card's memory as if it was (slow) local DRAM. But graphics cards are advanced devices with minds of their own (which means they're doing things all the time), so manipulating their memory means you have to handle concurrency and synchronisation between the main CPU and the card's own. So often cards don't expose all their memory, just a chunk they want to use to communicate back and forward with the system CPU. Right now cheap consumer cards seem to have around 64Mb of onboard RAM, so they probably map most or all of that into the CPU space. But high-end cards are getting on for 1Gb, and if they map all of that then they're consuming a big chunk of host address space (space you can't use to access local DRAM). One option is simply to go to 64bit, where the address space is vast and there's acres of breathing room for everything to be mapped into. Alternatively the card can choose to map only a portion of its memory into host space, and have some registers that allow the host to change that mapping (which is called a "window") on request. Accessing memory through a window is a pain for the device driver programmer, as he has to organise his operations accordingly (old graphics driver authors are used to this, as the same thing used to be necessary with older graphics interface standards). So the short answer is "4Gb is the limit, including all mapped graphics memory, but different graphics cards map their graphics memory into that 4Gb into different ways". 87.115.143.223 (talk) 11:42, 15 March 2009 (UTC)
- Out of interest I checked the memory map on my x86 linux machine (but much the same happens on Windows and OS-X) - it has a 128M nVidia GeForce memory card. Here's what
lspci -v
shows for it:
- Out of interest I checked the memory map on my x86 linux machine (but much the same happens on Windows and OS-X) - it has a 128M nVidia GeForce memory card. Here's what
02:00.0 VGA compatible controller: nVidia Corporation NV44A [GeForce 6200] (rev a1) Flags: bus master, 66MHz, medium devsel, latency 248, IRQ 19 Memory at e4000000 (32-bit, non-prefetchable) [size=16M] Memory at d0000000 (32-bit, prefetchable) [size=256M] Memory at e5000000 (32-bit, non-prefetchable) [size=16M] [virtual] Expansion ROM at e6000000 [disabled] [size=128K]
- Which means it's taking four distinct chunks of the CPU's memory map. I'd guess the two 16M ones are for command queues and control registers, and that big 256M one is for bulk data. Notice that the 256M is actually double the size of the card's 128M of memory: a common trick hardware designers do is to duplicate a block of memory, one with pages marked as cacheable and one with pages marked as non-cacheable, so software can use either mode as appropriate. I'm sorry if this seems like a diversion, but my point is to show that there frequently isn't that 1:1 mapping of device<-->system memory. 87.115.143.223 (talk) 14:09, 15 March 2009 (UTC)
Alan turing
Who is alan turing —Preceding unsigned comment added by Shushank22 (talk • contribs) 06:38, 15 March 2009 (UTC)
- Perhaps our article Alan Turing will answer your question. – 74 06:51, 15 March 2009 (UTC)
Ubuntu vs. Xubuntu
I have heard that Xubuntu is an extremely lightweight operating system, so when I get a new notebook, I was planning to install it. However, I just found a model that comes with Ubuntu. The notebook is very limited: 512MB RAM, and 4 GB hard drive space. Is Ubuntu also lightweight enough to work on that notebook? (I know that Windows or Ubuntu will work, but just taking up a lot of space). Thanks, Genius101Guestbook 13:55, 15 March 2009 (UTC)
- Ubuntu 6.10 ('edgy') requires a minimum of 400Mbytes of disk space - and a 'standard' installation needs 2Gbytes. I don't know about the latest version - but I doubt it's doubled in size - so it'll fit. The question is: How much space do you need for your stuff? A 4Gbyte drive is pretty pathetic by modern standards. However, (presuming you have a USB port) you can easily get the space back by buying a cheap 'thumb-drive'. If you Google "cheap thumb drive" - you'll see that they are currently selling for around $2 per gigabyte! So IMHO, go ahead and install Ubuntu in all of it's glory - and splurge $9 to get one of these 4Gbyte thumb drives to keep your 'user files' on...heck, go nuts, spend $20 and get an 8Gb drive - a big chunk of the cost is postage, so you might want to check out a nearby brick-and-mortar store instead. SteveBaker (talk) 14:16, 15 March 2009 (UTC)
- ...Or just spend $50 or so and upgrade the laptop harddrive to something more reasonable. I think I got a 300GB laptop drive for about $80 not long ago. Usually these sorts of things are best bought separately from the laptop itself (ditto RAM) as you can find them quite cheap elsewhere on the 'net (e.g. newegg.com), though you have to do the labor yourself... --98.217.14.211 (talk) 15:33, 15 March 2009 (UTC)
- I hadn't thought of the thumb drive, but that sounds like a good idea. Thanks! Genius101Guestbook 16:15, 15 March 2009 (UTC)
- Sounds like the OP is buying something like an EEE PC which has a 4gb internal solid state disk and no place to put a hard drive. Rather than a thumb drive sticking out the side you could consider an SDHC card. There are also replacement mini-pci ssd's available up to 64gb or 128gb for most of those netbook models now. Not all of them--some (including the EEE 701) have ssd's soldered onto the board. As for ubuntu, yeah, the base install fits on a cd-rom, but it is missing a lot of stuff (they fill most of the install iso with Office-like bloatware) and you will be in apt-get download hell for months after your initial installation. I'd expect xubuntu to be even worse. 75.62.6.87 (talk) 09:18, 16 March 2009 (UTC)
Mobile photo sharing
Hi, I'm looking for a photo sharing service accessible from a mobile (i.e. has mml) that has some sort of a private share method in which the viewer doesn't have to be a member, for example they just have to input a predefined password (that I have taught them) to see the images. Is there anything like that? All the ones I've found only have private sharing between members... I think. They can be pretty vague on how it works sometimes. Thanks! 210.254.117.186 (talk) 14:28, 15 March 2009 (UTC)
- And to clarify, apparently programs like coppermine do this for incoming links to private albums, but I don't have any server space so I'm looking for an online simple gallery-type service. 210.254.117.186 (talk) 15:00, 15 March 2009 (UTC)
- In general, I don't think you will find one unless it is provided by your cell phone manufacturer. I would try Facebook or Myspace, which might be built into your cell. Of course, there are all the photo sharing sites (e.g., Photobucket) which also require a username. Magog the Ogre (talk) 02:27, 16 March 2009 (UTC)
- Photobucket has the function to password protect albums like I need (I checked it yesterday), but it's mobile support is lacking, and you're limited to tiny thumbnails and a really ugly interface. I'm pretty sure it's pretty common, the only problem is that I have to register and try out each to find out what it's like, which isn't really cool. 210.254.117.186 (talk) 02:43, 16 March 2009 (UTC)
- In general, I don't think you will find one unless it is provided by your cell phone manufacturer. I would try Facebook or Myspace, which might be built into your cell. Of course, there are all the photo sharing sites (e.g., Photobucket) which also require a username. Magog the Ogre (talk) 02:27, 16 March 2009 (UTC)
Using Opteron 2000 series in a 4 socket motherboard
I bought a TYAN S4985 Quad Socket motherboard recently in order to build a 'god' gaming box.
In order not to rob a bank I am trying to figure out if it's possible to run two 2200 or 2300 series Opterons in two sockets, leaving 2 sockets empty, until the prices on the 8 way capable Opterons drop to a level I will pay. Currently the board is just sitting there while I look to ebay for a good Opteron deal.
There's not much information to be found regarding this issue around the web.
Also is it possible to use three 8 way opterons and IBM’s CPU Pass Thru card on a motherboard like mine and then reap the benefits?
85.81.121.107 (talk) 16:44, 15 March 2009 (UTC) Mopteron
Me again :-)
I found this website for a company called ISI, selling this
http://www.isipkg.com/cost_reduction_modules.php
Wondering if this is what IBM is calling a cpu pass thru card? 85.81.121.107 (talk) 19:42, 15 March 2009 (UTC)
Me again....I found this link, indicating that the 2000 series do indeed work, sweeeeet. Especially now the 2376 is so damn cheap...
http://www.spec.org/cpu2006/results/res2007q1/cpu2006-20061224-00182.html
This just makes me think why AMD does not advertise that you can go from one 2000 series to two before you have to switch to a 8000 series for 4 way fun. Anyway I'll buy the 2376s new and a single 2200 for bios upgrading if my S4985 needs a bios update to recognize the Shanghai's
If anyone can confirm that the 2300/2200 does work in a quad socket board please come forth. I also checked up on the cpu pass thru card, it apparently is a special cpu 'daughter' card for a specific IBM motherboard. It looks veryn much like the ones that were shown in the istanbul youtube videos'
Would be sexy though to have a drop in pass trhu socket 'enhancer' for three way play.
85.81.121.107 (talk) 02:55, 17 March 2009 (UTC) Mopteronto
annotating pdf files
Is there any free program out there that I can download that would let me annotate a pdf file? I mean this as in the ability to highlight certain areas, write things in the sidebars or on white space between lines, or even draw lines or circles around things, and then save it for reference later or print it. —Preceding unsigned comment added by Yakeyglee (talk • contribs) 16:44, 15 March 2009 (UTC)
- If you only care about a single page, Inkscape can open almost all PDFs and then you can draw text and graphics on it to your heart's content (and then save back as PDF). Unfortunately Inkscape will only open a single given page of a PDF, so (while it is possible to chop and reassemble PDFs using free tools) I guess you might find this tiresome. 87.115.143.223 (talk) 17:01, 15 March 2009 (UTC)
- Foxit Reader will allow you to do this. The free version will mark the PDF with an evaluation stamp in the top-right of every page, which may or may not matter to you. — Matt Eason (Talk • Contribs) 17:58, 15 March 2009 (UTC)
Am I allowed to be using a pirated version of windows?
I have a dell computer and when I bought it, it came with a cd but I lost it. Am I allowed to use a fake cd from my friend? I even have a sticker on the side of my computer that says certificate of autheticity.--75.187.113.105 (talk) 20:41, 15 March 2009 (UTC)
- Windows licensing is very complex, and we're not allowed to give legal advice. Dell will, however, sell you a recovery CD at a pretty low price (something like $10). 87.115.143.223 (talk) 21:00, 15 March 2009 (UTC)
- If you have an authentic Windows serial number then I doubt anyone cares -- it's not really the disk you're buying, but the license to the software. The sticker on the side doesn't mean anything in this case. --98.217.14.211 (talk) 22:51, 15 March 2009 (UTC)
- The sticker on the side will be an OEM licence. For that licence to work with the disk it has to be an OEM disk (and most likely the same class of OEM, and for the largest manufacturers the same OEM). Windows licences, even for products that are (to the end user) the same, are varied and mutually incompatible. It might work, but for a Dell I doubt it. 87.115.143.223 (talk) 23:46, 15 March 2009 (UTC)
Yes you are, as long as it is the exact same version of Windows. I even had a friend who got a computer with the sticker at an auction: he called in to Microsoft who promptly sent him a Windows CD in the mail. Just make sure you use the same registration number as the sticker on the side of your computer. Magog the Ogre (talk) 02:23, 16 March 2009 (UTC)
- Getting a replacement CD is not the same as using a pirated CD. Taemyr (talk) 03:36, 16 March 2009 (UTC)
- Unless I am sorely mistaken, each Microsoft replacement CD has its own license. One may use an old CD for his/her system if s/he owns the license. Magog the Ogre (talk) 03:39, 16 March 2009 (UTC)
Can this fax?
When I bought my current system, I was still on dial-up, and the modem card also came with some faxing software, which I used only occasionally. Today I'm on DSL with a home network: Computer connected to the router, router connected to the DSL modem, DSL modem connected to the phone line -- but I am faxless. From the point of view of the telephone wire, it goes wall -> DSL modem -> phone, and not through the computer case.
- Option A is: buy a phone line splitter, and run a short wire from the splitter to each modem. This would allow the fax modem to "see" a phone line and use it when needed. Or would it?
- Option B might be: run the phone line from the wall, to the fax modem, to the DSL modem -- daisy chain them both onto the same run.
- Q1: Which of those is better, or worse, than the other? (Is one of them a spectacularly bad configuration?)
- Q2: In the first option, I could probably plug the phone into either modem, yes? But perhaps connecting the phone to the fax modem is a bad idea, as it might require one of those line filters that I have to have on every other phone in the house. Or do I have to have that upstream of the fax modem anyway, even without a phone on it?
Thanks in advance! --DaHorsesMouth (talk) 23:04, 15 March 2009 (UTC)
- So, to clarify, it seems you don't have a DSL filter (or, then, that the DSL filter is inside your DSL modem's casing)? If that's the case, are you confident that the phone connection is really an analog phone (and not a digital phone connection supplied by the internet company and carried over the DSL)? 87.115.143.223 (talk) 00:10, 16 March 2009 (UTC)
- Yes to both. There is no DSL filter required on the wire that goes to the DSL modem itself, just on every other phone jack in the house; this according to Qwest. Am I confident in the phone? Yeah, I've been using it as a telephone for a couple of decades, and it worked fine as a phone and a fax when the wire went to the back of the computer case (same computer) and thence to the phone on the desk. Same phone, same wire, same wall jack. --DaHorsesMouth (talk) 01:58, 16 March 2009 (UTC)
- Your best bet is probably to split the "phone" output from the DSL modem into both your phone and fax-modem. There's no guarantee this will work if, for instance, you have digital phone service, but I don't think it would cause any line problems either. As an alternative, you might want to consider using an internet fax service to send and receive faxes instead. – 74 00:57, 16 March 2009 (UTC)
- Split it "downstream" from the DSL modem? Hadn't thought of that option. Will try that after I buy my splitter... Thanks! --DaHorsesMouth (talk) 01:58, 16 March 2009 (UTC)
Comparing variables in C++
I am writing up a program in C++ and at one point I need to check if ten variables (call them t1,t2,...,t10 and they are all floats) are equal or not. If they are all equal, then I need to execute some commands otherwise the program keeps going. My questions is that is it better to do
if (t1==t2) && (t2==t3) && ... && (t8==t9) && (t9==t10)
compared with
if (t1==t2) { if(t2==t3) { if(t3==t4) ... } }
as nested if statements? In the second case, I know that not all ten conditions will be checked unless all ten have the same value. Does that also happen in the first case? Will all ten conditions always be checked in the first case or will the checking stop as soon as first false is found? The reason I ask is because this is all inside a loop which will be executed about times so usually, the difference in overhead will not make a difference but in my case, if there is a difference, the difference will be huge in execution time. So obviously I want the faster one. I know that if statements can be costly but which one is less costly?
I am calculating a value recursively and I want the loop to stop if the value doesn't change for ten consecutive iterations. If anybody have any better suggestions (smarter/faster) on how to test ten variables for equality with each other or how to make the loop stop, let me know. BTW, I am only an intermediate C++ user and I am doing this for a math project. I am using a do while loop working on a dual processor Linux machine using the built in g++ compiler. Thanks!-Looking for Wisdom and Insight! (talk) 23:25, 15 March 2009 (UTC)
- Evaluation of && and || is left->right lazy, so f&&a where f==0 will never evaluate a, and t||b where t==1 will never evaluate b. There isn't an obvious speedup, and the two approaches you describe will probably be equivalent (as will "clever" stuff like using arithmetic in place of some booleans, or using ?:) - compilers are good enough now that cleverness just fools them into producing worse code. There might be a slight speedup with your first method, if the compiler has an optimisation targetted at such a (fairly common) case. The only speedup I can suggest is to consider the relative probabilities of each comparison being false; if they're all the same, just do them as you've done in logical order. But if some comparisions are more likely to be false than others then do those before the rest - that way you'll reject the failing cases sooner (on average). 87.115.143.223 (talk) 00:05, 16 March 2009 (UTC)
- Why exactly do you have ten variables to be tested in a loop? If this is simply your test for "ten consecutive non-changes" consider rewriting it to keep a count of non-changes instead. That is, you calculate value x, then calculate value x+1 and compare them. If equal, increment non-change-count, else set non-change-count to 0; then loop. Exit the loop when non-change-count reaches 9. That loop structure uses a total of 2 comparisons per iteration instead of 10. – 74 00:50, 16 March 2009 (UTC)
- I think you have one other "interesting" problem to solve using your primary algorithm, that being, "On any given iteration through the loop, how do you know which t to set?"
- Further, suppose you've found three in a row that match, so that t1, t2 and t3 are equal, but the next time through something jiggles and it doesn't match. Which t will you set -- 4 or start over at 1? That's a bookkeeping problem in its own right.
- --DaHorsesMouth (talk) 02:11, 16 March 2009 (UTC)
Ignore all of the above: your answer lies in the fact your first statement is done via short-circuit evaluation (if you wanted to turn off short-circuit evaluation, you would use only one and(&) or or(|) symbol). The first statement in assembly language is identical to the second in assembly language. Magog the Ogre (talk) 02:19, 16 March 2009 (UTC)
- Also note that you shouldn't use == with float (or double) values. Once you get some imprecision going, you can set a=1.0 and b=1.0 and then find that a==b returns false. -- kainaw™ 02:49, 16 March 2009 (UTC)
So I am short circuiting, right? Because I am using the double ampersand sign &&. So this means that the expressions are evaluated in order and soon as one is found false, the entire expression is false and the rest are not evaluated, right?-Looking for Wisdom and Insight! (talk) 05:09, 16 March 2009 (UTC)
- Yes, && short circuits. But doing that comparison with ten variables is a horrendous code smell. Use an array, or a linked list wound through the call stack (shallow binding) or anything sane, just not ten variables. 75.62.6.87 (talk) 09:21, 16 March 2009 (UTC)
- As stated above, a loop with 10 exit-condition comparisons is generally bad practice regardless of whether the values are stored in variables, arrays, or some other data structure. You should try to keep your loop as simple as possible, but no simpler. – 74 16:49, 16 March 2009 (UTC)
- Woahhhh! Wooooaaaah!!!!. You said "The reason I ask is because this is all inside a loop which will be executed about times so usually". Um...oops! Let's back up a bit here. Are you saying your loop runs 10200 times?!?! Let's suppose you have a state-of-the-art 4GHz CPU - that's 4x109 clocks per second. If you entire loop could execute in one clock tick (certainly it can't) then it's going to take 10199 seconds to finish...there are about 3x107 seconds in a year - so even with the most optimized possible program on the fastest CPU available - it's going to take 10192 years...that's a LOT longer than the life of the universe so far - certainly, the Sun will burn out and the earth will be a crispy cinder before your program is even a millionth of a millionth of one percent of the way to completion! This is not a matter of optimization. This is a matter of a total rethink of the entire possibility of doing the calculation! SteveBaker (talk) 04:50, 17 March 2009 (UTC)
March 16
Saving output in a text file
I have another question. I am a very novice user on Linux. How can I get my program (after I compile it) to run in the background so that I will have the shell available to me and I can log out of the computer and then check back the next day? What exactly is the command? In addition, I am using cout in my code for output which shows up in my shell. How can I get that display to be saved in a log file or something? I know I can always code it to write to a file but besides that what is the command to make it save the output in a text file?
Right now, I am using
g++ program.cpp
./a.out
Thanks!-Looking for Wisdom and Insight! (talk) 01:05, 16 March 2009 (UTC)
- You might find Redirection (Unix) and Job control (Unix) helpful. – 74 01:15, 16 March 2009 (UTC)
Dude, that was awesome. That is exactly what I was looking for. Thanks a lot man!-Looking for Wisdom and Insight! (talk) 01:35, 16 March 2009 (UTC)
i was wondering this my self the other day....
this is the best explanation that i found: http://www.tuxfiles.org/linuxhelp/iodirection.html
Basicly use a close bracket and then filename after the command that you are running —Preceding unsigned comment added by 86.149.254.51 (talk) 03:09, 16 March 2009 (UTC)
Preventing PLESK from disclosing my email address
I have a PLESK VPS hosting account running on Apache/2.0.55 (Ubuntu)
Due to my set up, i occasionally get an error message that is showing on my site:
Object not found!
The requested URL was not found on this server. If you entered the URL manually please check your spelling and try again.
If you think this is a server error, please contact the webmaster. Error 404 www.example.com Mon Mar 16 00:05:43 2009
On the 3rd line of text the word "webmaster" is converted to an A tag with href pointing to my my emailaddress
I UNDERSTAND what and why a 4040 error might occur
BUT i don't understand how to turn it off.
Or more exactly - how to prevent the darn server from displaying my email address to all and sundry.
I really think its a silly idea to give away the main admins email address because its a bit like saying "if you want to hack this server - here's the weakest link"
Perhaps somwone could suggest a grep search thatr works ...i tired:
grep "If you think this is a server error, please contact"
But that that did not seem to dig up anything on the box
I have looked into the error_docs folder on a couple of my vhosts directories ...but no error docs look like this message.
It seems to be an apache error notice
Anyway - thanks in advance for any help and tips.
generally - I'd really love to know how to lock down a PLESK server to prevent it from revealing my personal details. —Preceding unsigned comment added by 86.149.254.51 (talk) 03:01, 16 March 2009 (UTC)
- Do you actually have to login with your email address, because if not I'd question if it really does weaken your server security, but you are right and it is indeed an Apache "error". Normally you would change ServerAdmin in the vhosts or better yet add an ErrorDocument line to point it to a file, but I'm assuming you don't have access to the Apache config files (you said it's a hosted account so I seriously doubt you do).
- In the root of your website you could try creating a single file called .htaccess (with the . as the first character) with the contents of:
- ErrorDocument 404 /404.html
- And then any files not found would display http://www.yoursite.com/404.html instead. Please note this is completely reliant on your host allowing .htaccess overrides and if it doesn't work then I'm afraid there isn't much you can do except contact them and ask for them to setup a custom 404 error page like the others. Hope this helps! ZX81 talk 09:59, 16 March 2009 (UTC)
RAID with different sizes of disks
What implementations of RAID 1, 5 and 6 can be used with disks of unequal capacity? NeonMerlin 04:45, 16 March 2009 (UTC)
- See JBOD. I think it is not logical with any of the raid modes you mention. 75.62.6.87 (talk) 09:35, 16 March 2009 (UTC)
- It depends how fussy your RAID controller is, but yes, you can use disks of different capacities with RAID 1, 5 and 6, but the RAID array on each disk will only be as large as the smallest disk (and the remaining space on each disk will be unused/wasted). ZX81 talk 10:03, 16 March 2009 (UTC)
Allowing blocked users to edit cetain pages
The reference desk seems to be an inappropriate place to ask this question, but developers at mediawiki.org reply to questions posted at mw:Project:Support desk rather slowly...
Anyway, here is my question: when $wgBlockAllowsUTEdit is set to true, blocked users will be able to edit their own talk pages. However, is it possible to allow blocked users to edit certain pages(something like Wikipedia:Appealing)? Regards.—Bencmq (talk) 05:42, 16 March 2009 (UTC)
- Try WP:HD —Preceding unsigned comment added by 194.80.240.66 (talk) 08:17, 16 March 2009 (UTC)
- No, this question is not about Wikipedia. It's about MediaWiki. --wj32 t/c 18:08, 16 March 2009 (UTC)
- If memory serves there is a feature that allows you to limit given users to certain namespaces. The intention for this was that the arbcom would be able to interdict individuals, and they'd be able to edit the arbitration namespace, but not the article space. This is an alternative mechanism to blocking, I think. 87.113.41.20 (talk) 21:38, 16 March 2009 (UTC)
- Using that method will require you to put the "special" pages in a special namespace. If you haven't created special namespaces yet, look into it on mediawiki.com - it isn't too difficult. Just remember that you need to declare both the namespace and the talkspace for the namespace. I messed that up the first time and when you clicked "discussion" in one namespace, it jumped to another namespace. -- kainaw™ 22:25, 16 March 2009 (UTC)
- Actually there is a discussion going on at zhwp regarding the appealing procedure after blocking. Anyway, they shall ask bugzilla. Thank you for all your help. --Bencmq (talk) 02:50, 17 March 2009 (UTC)
- Using that method will require you to put the "special" pages in a special namespace. If you haven't created special namespaces yet, look into it on mediawiki.com - it isn't too difficult. Just remember that you need to declare both the namespace and the talkspace for the namespace. I messed that up the first time and when you clicked "discussion" in one namespace, it jumped to another namespace. -- kainaw™ 22:25, 16 March 2009 (UTC)
Thunderbird reply quote header
Currently when I reply to a mail, Mozilla Thunderbird just puts "So-and-so said:" before the quoted text of the original email, which is not very descriptive. I know that some other people's email clients include stuff like the date and subject, like this:
-----Original Message----- From: So-and-so Sent: Thursday, January 1, 2009 12:00 AM To: Me Subject: foobar
How do I customize my Thunderbird reply quote header to be more like that? --76.167.241.45 (talk) 09:24, 16 March 2009 (UTC)
- I'm not sure how to make Thunderbird display full headers for quotes, but it's always there. Gmail, for example, shows nice quotes and hides the full headers. You can still view them by using "Show original message". --wj32 t/c 18:15, 16 March 2009 (UTC)
- You don't get it. It's not "there" if the email client that made the reply doesn't put it there. That's the problem. You can't tell me that it's there when it is not. Gmail hides quotes and you can show them, but of course it can only show what is there. So it only shows what my email client puts there, which is just "So-and-so said:". Why don't you try this yourself? --76.167.241.45 (talk) 05:05, 17 March 2009 (UTC)
- Sorry. Perhaps this can help you: [2]. --wj32 t/c 05:36, 17 March 2009 (UTC)
want to remove U3 from my pen drive
I bought a Sandisk pen drive (Cruzer titanium) which worked ok under Fedora Core 3 (i.e. I didn't notice at the time that the drive has U3, since it didn't show up). Now under Fedora 10 the U3 partition appears as a CD drive and offers to (hah!) autorun the windows exe's in the U3 partition. I don't run Windows and want to get rid of the U3 crap completely. Any idea how to do that (without running windows code, of course)? The U3 article seems to have been the locus of some, er, partisan editing and looking through the rev history there were once some mentions of useful info existing somewhere, but not enough to make it easy to locate any. Thanks 75.62.6.87 (talk) 09:26, 16 March 2009 (UTC)
- I'm afraid you'll need access to a Windows machine to remove it, but you simply need to download the executable from the U3 website and just run it whilst on a Windows PC with the U3 flash drive connected. The process only takes a few minutes, but as you probably guessed it will wipe the flashdisk in the process. ZX81 talk 10:07, 16 March 2009 (UTC)
- Wouldn't blasting and restoring the partition off the drive (with, for example, gparted) achieve the same result, without resorting to booting to windows and running yet more mystery software? Dog Day Today (talk) 12:30, 16 March 2009 (UTC)
- Unfortunately, no. It appears that the U3 flash drive has firmware on it that presents the extra volume, and no amount of fdisk, parted, or even dd would make it go away. -- JSBillings 13:09, 16 March 2009 (UTC)
- You can use the partition manager in Windows (I used XP) to eliminate the factory set partitions. --Ephilei (talk) 18:58, 16 March 2009 (UTC)
Vista and Outlook
I am trying to copy my past e-mails onto a new vista machine. What sub-folder should I copy the pst files into? Kittybrewster ☎ 12:57, 16 March 2009 (UTC)
- On my Vista machine, the default path to "Outlook.pst" is
- C:\Users\<User Name>\AppData\Local\Microsoft\Outlook\
- --Andreas Rejbrand (talk) 14:08, 16 March 2009 (UTC)
- How do I get to see that place in windows explorer? I can't get into AppData though it tells me it already exists when I try to create it. Kittybrewster ☎ 14:45, 16 March 2009 (UTC)
- (Oops; these instructions are for Windows XP, and Microsoft hid the option elsewhere in Vista. Sorry for the confusion; please follow Wj32's directions below instead.) Windows is "protecting" you. To disable this "feature" in Explorer, go to "Tools → Folder Options… → View" and select "Show hidden files and folders" then click "OK". – 74 16:41, 16 March 2009 (UTC) (edited – 74 20:22, 16 March 2009 (UTC))
- Using firefox but tried in IE. Tools .... options ... then I can't find "View". Kittybrewster ☎ 17:27, 16 March 2009 (UTC)
- (Oops; these instructions are for Windows XP, and Microsoft hid the option elsewhere in Vista. Sorry for the confusion; please follow Wj32's directions below instead.) Windows is "protecting" you. To disable this "feature" in Explorer, go to "Tools → Folder Options… → View" and select "Show hidden files and folders" then click "OK". – 74 16:41, 16 March 2009 (UTC) (edited – 74 20:22, 16 March 2009 (UTC))
- How do I get to see that place in windows explorer? I can't get into AppData though it tells me it already exists when I try to create it. Kittybrewster ☎ 14:45, 16 March 2009 (UTC)
- Not Internet Explorer. Windows Explorer. Open up Documents. Press Alt and the menu bar will appear. Go to Options → Folder Options → View. Alternatively you could just type in
C:\Users\<user name>\AppData\Local\Microsoft\Outlook\
into the address bar. --wj32 t/c 18:12, 16 March 2009 (UTC)
- Not Internet Explorer. Windows Explorer. Open up Documents. Press Alt and the menu bar will appear. Go to Options → Folder Options → View. Alternatively you could just type in
- The simplest way to open a particular folder in Windows, hidden or not, it to use the "Run" command. Simply press Win+R, type the path (e.g. C:\Users\<User Name>\AppData\Local\Microsoft\Outlook\) and press Enter. --Andreas Rejbrand (talk) 20:21, 16 March 2009 (UTC)
- I'm sorry if I'm wrong because I'm not a Vista user, but 2k and XP have a folder option shortcut in Control Panel. Try to see Control Panel. Oda Mari (talk) 16:03, 17 March 2009 (UTC)
Multiple live video on a single screen
Hello! We're conducting an event, and we have several live videos being shot from various angles. Is there a way to get all these videos onto a single display that can be projected onto a screen? Do I need any special hardware for this? And what software do I use? I'd really appreciate a solution that would not involve buying new hardware.--Seraphiel (talk) 15:50, 16 March 2009 (UTC)
- What you appear to be asking for is a video splitter. I know it sounds backwards. It sounds like you are taking a single video and splitting it up. What it actually does is take multiple video inputs and splits the screen into sections such that each video may be shown on the screen at the same time. I am sure there are programs that can do this, but you'll have to figure out how to get multiple video inputs into the computer. All those video cards will likely be more expensive than a video splitter - especially just leasing one from a local dealer. -- kainaw™ 22:22, 16 March 2009 (UTC)
March 17
Creating a strong password, valid characters?
I want to create a password that will be difficult to guess or crack. I would also like to include non-standard characters that aren't alphanumeric, so those that include !,@,#,$,%,^,&,*, etc... However, sometimes I will encounter a website that does not allow the use some of those characters. Some may consider '#', '@', or '%' invalid, but allow '&' or '~' at other times. So my question is, what is the minimum set of characters (beyond alphanumeric) that most websites employ? Thanks. —Preceding unsigned comment added by 141.153.215.194 (talk) 04:19, 17 March 2009 (UTC)
- That's tough to say when asking what "Most" sites employ, but in my years of experiences it seems that "8" is a common minimum for password strength. (goes back to the bit/byte thing = 64). — Ched ~ (yes?)/© 06:53, 17 March 2009 (UTC)
- Number of characters isn't the question. My guess about character set is that the simple ASCII will always be game. You use the typical 26 characters x 2 for case sensitive, plus 10 for numerals, and you're pretty good. With 8 characters you're doing alright with 218,340,105,584,896 combinations. You'll realize that upping the char-set is often more useful than upping the characters. Just make sure you have a random generator that will permit those characters. If you can't do that, then use something that gives you the full character set, then just remove the ones it won't take by yourself. Try a command like openssl rand -base64 128 or dd if=/dev/urandom bs=16 count=1|xxd. Shadowjams (talk) 07:03, 17 March 2009 (UTC)
- Instead of a password you could also create a pass-sentence. It can have 40-50 characters, be easily memorized and extreme secure.--Mr.K. (talk) 12:01, 17 March 2009 (UTC)
- What special characters are allowed depends on the programmer and system. For example, I work in two universities and I move a lot of files back and forth between the two. So, I wanted to use the same passwords on each. One requires 8 characters with at least one number, one letter, and one "special character" limited to something in the set "._+-!$%&" (a very small subset of ASCII). The other required nine characters, at least one capital letter, one lower case letter, and two characters in the set "!@#$%^&*()_+-=,." (still a subset of ASCII). Knowing the programmers on both sides, I asked about the weird restrictions on the special characters. They said it had to do with limitations on internal programs such as Oracle pitching a fit if you used a @ in your password or some Windows file share crapping out if you used a \. Therefore, it is not possible to have a single set of password restrictions that EVERYONE will use - and you don't want it anyway...
- Assume you come up with the biggest badass uncrackable password ever. You use it on EVERY site you access. Well, the admins at those sites will know your password. They don't need to crack it. You've just trashed your security. What you need is a unique password for each site - something that a keyring makes easy to do. There are even keyrings that have password makers so you can have high-security and unique passwords for each site. -- kainaw™ 13:25, 17 March 2009 (UTC)
- As another example, Wikipedia is extremely lax when it comes to passwords. They can be thousands of characters long (I forget the limit, but it's something ridiculous) and contain all kinds of crazy characters (I just changed my alternate account's password to 'ῸὸὈὀὉὁὌὄὊ', for example). However, this doesn't add any extra security, since the password is stored as a 128-bit MD5 hash anyway. Algebraist 14:13, 17 March 2009 (UTC)
- When exactly is 128-bit MD5 storage (for typically plaintext transmission!) "extremely lax" security? -- Fullstop (talk) 15:32, 17 March 2009 (UTC)
- Sorry, I was unclear. I meant Wikipedia is not at all strict when it comes to what characters you're allowed. None of the restrictions mentioned above apply here. Algebraist 15:34, 17 March 2009 (UTC)
- When exactly is 128-bit MD5 storage (for typically plaintext transmission!) "extremely lax" security? -- Fullstop (talk) 15:32, 17 March 2009 (UTC)
- The rules of thumb for "a password that will be difficult to guess or crack" are: a) not a dictionary word; b) not easily guessable (not the name of a relative, pet, phone number, SSN, name of your personal obsession or other personal numbers/names); c) has characters that come from all sections of the character set (numerals, upper case letters, lower case letters, punctuation, etc); d) The adage "longer is better" is often still true.
- The crux is always the ability to remember the phrase you used, but you can usually fulfill all the "hard to guess" requirements by interpolating substitution values into an easily-remembered passphrase. E.g. use a couple of l337-speak vowels, or IPA symbols, or even just (from using adjacent keys on your keyboard) replace "q" etc with "12" or "!@" etc. You get the idea. -- Fullstop (talk) 15:32, 17 March 2009 (UTC)
- Best approach is to pick two or three words from a dictionary completely at random (i.e. by rolling dice, flipping coins, etc) rather than trying to think up a password, rely on weird characters, etc. You can separate them with hyphens, like "widget-giraffe" or whatever. See www.diceware.com or diceware for an approach to this. It explains how to quantify how random a password is, using the Shannon entropy. The entropy measure you actually want is the min-entropy, but in this specific situation it will be very close to the Shannon entropy, so the Shannon entropy approach will be plenty good enough. —Preceding unsigned comment added by 75.62.6.87 (talk) 22:08, 17 March 2009 (UTC)
- Wouldn't that be susceptible to an advanced dictionary based attack? - Jarry1250 (t, c) 22:12, 17 March 2009 (UTC)
- It could be vulnerable to an offline dictionary attack, if the attacker had (say) a hash of the passphrase. The same would be true of a single word with non-alphabetic symbols. Two or three words should be enough to stop an online attack (one where the attacker has to submit one guess after another to the server) since it would take millions of tries and the server should lock the attacker out long before that. With five or six words, there should be enough entropy to stop all but very large scale offline attacks. This is all explained (including the math) at the diceware site. 75.62.6.87 (talk) 22:20, 17 March 2009 (UTC)
- Even "very large" offline attacks would be pretty computationally difficult. I don't remember the limit but at some point you get beyond the ability to computer it in a reasonable (e.g. your lifetime) amount of time—each word you add exponentially increases the number of possibilities. You can think of the random dictionary words bit as using a four letter word, but with an alphabet that contains around 500,000 letters. I would expect that is a lot better than the sorts of "add an extra, non-alphanumeric" character sort of thing where you're just increasing the letters by one each time. --98.217.14.211 (talk) 23:43, 17 March 2009 (UTC)
Google print size
I must have hit some combination of keys because when I search from the toolbar, I get bigger letters than normal. How do I reset it? I'm using Firefox 3.0.7. Clarityfiend (talk) 06:55, 17 March 2009 (UTC)
- Try Cntrl+-
- Ctrl+0 (that's a zero). --wj32 t/c 07:34, 17 March 2009 (UTC)
- Or View + Text Size + Normal. StuRat (talk) 14:44, 17 March 2009 (UTC)
- Or use your mouse's scroll wheel while holding down the Ctrl key. --Andreas Rejbrand (talk) 15:17, 17 March 2009 (UTC)
- Thanks. Clarityfiend (talk) 19:39, 17 March 2009 (UTC)
Getting the commit charge limit
I'm trying to get the Commit Charge Limit as displayed by Process Explorer. Both GetProcessMemoryInfo (from psapi.dll) and NtQuerySystemInformation (with SystemPerformanceInformation) work fine on XP. But on Vista, both report the peak and limit to be 16EB! Process Explorer still reports the correct value. Any ideas? Thanks in advance. --wj32 t/c 08:51, 17 March 2009 (UTC)
- I'm such an idiot. The old integer overflow problem. --wj32 t/c 09:06, 17 March 2009 (UTC)
Adding five more users to an existing 25 user Novell netware 4.2 version
Novell netware is now not available. I have a 25 user Novell netware 4.2 version running successfully for the last 25 years. Now I am in need of adding five more users to that. But the software for adding additional five users is not available from Novell. Is there any other method or shortcut to add five more users without disturbing the existing network. or If a 5 user adding software available with anyone please help me. —Preceding unsigned comment added by 61.17.229.4 (talk) 09:15, 17 March 2009 (UTC)
Screen quality
Which mobile phone has the best screen in terms of quality? Is it the iPhone? —Preceding unsigned comment added by 116.71.46.119 (talk) 17:24, 17 March 2009 (UTC)
- I think you'll have to clarify what you mean by "quality" as that'll change from person to person. Personally I find the higher the resolution of the screen then the better the "quality" because it's sharper and easier to read. The iPhones resolution is 480x320 and there are phones with much higher resolutions that that (for example the very old HTC Universal or the much newer HTC Touch Pro and there are many others). Sorry if that's not a lot of help. ZX81 talk 22:31, 17 March 2009 (UTC)
irc help
i made an irc channel on freenode or whatever how do i make mself and friends operators on it? cant figure out how--Raisens2 (talk) 20:40, 17 March 2009 (UTC)
- Assuming the channel isn't already registered, the first person to create it should get operator status and from there you can then /msg chanserv help for more information about registering the channel (if you haven't already registered a nickname you'll need to do that with nickserv first). If it's already registered then there isn't really much you can do I'm afraid except pick a new name or ask the channel founder (if known). ZX81 talk 22:37, 17 March 2009 (UTC)
Windows Family Censorship - or whatever it's called
I made the mistake of downloading the MS Office add-on called 'Workspaces', only to find that not only did the 'button' in Office only remain for an hour or so, I had also had the misfortune to be stuck with a Family Control Filter which I didn't ask for nor want. Now the damn thing asks me to log-in and approve practically every website I visit, including Wikipedia and even the BBC News, saying that it's blocked. This is not a virus or anything I downloaded from the wrong site, as all my other PCs can use it. I am having this problem only on the one PC I use the most, and it is extremely annoying, true to Microsoft fashion. Can anyone give me any idea how to get rid of the thing? Plus, as an extra, why would a family control filter come with an office workspace? Why would I let kids play around with my office computer? No need to answer that. We all know MS's marketing 'skills'.--KageTora (talk) 23:01, 17 March 2009 (UTC)
- OK, I did it. For information purposes, I will tell you that it appears as Microsoft Family Safety Filter as well as Windows Family Safety Filter, apparently to make it difficult to find (as well as the fact that it is in some folder that doesn't appear on the uninstall list). The way to get rid of this is to wait until a website is blocked and click on 'Go to Website', then you get yet another pop-up with a button asking if you want to turn it on or off. Turning it 'off' is the right option. Then go 'Start Up programs' and remove it from the list. You can disable it from their without going to the website, but I made the mistake of removing it first, which meant I had to search around for it again. Bloody labyrinth of crap, MS. Bring me back my Mac!--KageTora (talk) 23:28, 17 March 2009 (UTC)
March 18
C#.. how to show a tooltip anywhere on my screen?
I'm developing a C# application, and i need to show a tooltip to the user at the cursor's position. wherever the cursor is, even outside the form of my application. PS:I pay alot of attetion to the performance. any idea? Thanks in advance Supersonic8 (talk) 00:21, 18 March 2009 (UTC)
- Put a ToolTip control on your form/whatever control you want. When you call
ToolTip.Show
(or whatever it's called) it shows the tooltip relative to the control's location. Take a look at thePointToClient
function on every control. What you want to do is to convert a screen point into a point relative to the control's location. --wj32 t/c 07:44, 18 March 2009 (UTC)
Effect on humans
What is the effect on humans when they work continiously with out a break on a computer for 180days? —Preceding unsigned comment added by 220.227.88.91 (talk) 01:52, 18 March 2009 (UTC)
- Well the worst effect will be sleep deprivation, if you really mean "without a break". (Assuming, of course, they are allowed to eat and drink fluids.) --98.217.14.211 (talk) 02:45, 18 March 2009 (UTC)
- Lee Seung Seop. - Akamad (talk) 02:46, 18 March 2009 (UTC)
Problem with software requiring Adobe Reader
I am working with a PC running Windows XP. It is my family's computer. They aren't so good with computers and as I am home for a few days, I am douing some general software maintenance for them. I do certain things out of principle (mostly) such as using Firefox instead of IE and using Foxit Reader instead of Adobe Reader for pdf files. My brother received some proprietary software from his school on CD which I installed for him. This software is reference software. It seems to simply organize a bunch of pdf files. When it is run it calls on Adobe Reader to view these files. So, now that I have uninstalled Adobe, my brother's software does not function (at all). The desktop shortcut it installed calls an ini file. I am pasting the ini file contents below just in case they may be useful (If you are sure it isn't helpful and is just wasting space, feel free to remove it and this reference to it). Is there a way to make this software use Foxit instead?
- [General]
- Encrypted=1
- Title=Airworthiness Directive CD
- ShowTitle=0
- ADs=1
- BadPrint=0
- Debug=0
- HelpFile=avant.hlp
- SortOrder=0
- DisplayWeight=0
- Fuzzy=0
- ClosePrompt=1
- SkipSummary=0
- PFAAvoid=1
- [DB]
- DB0=Airworthiness Directives,\ADs,ADs
- DB1=Federal Aviation Regs.,\FARs,FARs
- DB2=Advisory Circulars,\ACs,ACs
- DB3=Service Bulletins,\SBs,SBs
- DB4=TCDs,\TCDs,TCDs
- DB5=NPRMs,\NPRMS,NPRMs
- DB6=STCs,\STCs,STCs
- DB7=CARs,\CARs,CARs
- DB8=CAMs,\CAMs,CAMs
- DB9=MMELs,\MMELs,MMELs
- [Path]
- DataPath=E
- Home=E
- \title.pdf
- QueryPath=E
- Version=E
- Save=C
- \Avantext\Reports
- IndexPath=E
- \DB
- AVDPath=E
- \DB
- [Settings]
- [Search]
- Fuzzy=False
- SortOpt=False
- DisplayWeight=False
- Duplicates=True
- MaxHits=2000
- LineItemHits=1
- ShowSupers=1
- [Client Info]
- Name=
- Addr1=
- Addr2=
- Addr3=
- Phone=
- EMail=
- [FormEdit]
- SavePath=C
- \Avantext\Forms
- [Volume]
- Disk1=E
- Disk2=C
- \Avantext\Disk2
- [Addon]
Chrissekely (talk) 04:32, 18 March 2009 (UTC)Chris
wii mod chip
is a wii mod chip required to play downloaded games on the wii system —Preceding unsigned comment added by 97.116.45.221 (talk) 04:18, 18 March 2009 (UTC)
Lahey compiler (FORTRAN programming)
i am using Lahey 95 compiler,i have run some programmes with this, my one programme is not running. after compiling it tells some warnings but zero errors ( it was running some programmes with warnings earlier) and it is nor creating .exe file, is it creating it somewhere else, can anyone suggest what should i do? —Preceding unsigned comment added by 203.199.205.25 (talk) 05:45, 18 March 2009 (UTC)
Databases
How can I test the efficiency of databases in Microsoft Access and the effectiveness of the database and database reports? --124.254.77.148 (talk) 05:51, 18 March 2009 (UTC)
Lookup table Excel
I want create a structure in MS Excel that allows me to select a value from a table by "addressing" it with the value from a specific cell, just like a lookup table or, in other words, if I was dealing with a database, the SQL query I'd use would be like "SELECT x FROM y WHERE k = m", where "m" would be the value of the mentioned cell that changes dinamically according to some variables, "x" would be the column of the table "y" containing the value I want and "k" would be the value I want to test. Is that possible? —Preceding unsigned comment added by 213.13.148.4 (talk) 09:26, 18 March 2009 (UTC)
- Have you tried using the 'if' command? Googlepeek here. Lanfear's Bane | t 09:35, 18 March 2009 (UTC)