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August 13

Force http (unsecure) connection.

Firefox redirects me to https, (No, the site doesn't do it), and I'm a bit frustrated, with https I start to get all kind of errors, images load slower, content load slower, captchas don't work, or connection times out (Also, it's easier to debug problems), instead with http, it works just fine, google chrome doesn't force https, so the page I'm working works just fine, I don't mind at all if it's unencrypted, how I can stop this behavior? 190.158.212.204 (talk) 00:08, 13 August 2012 (UTC)

Firefox doesn't just decide to force you to use https when you and the site say otherwise. I'd guess you have a security-enhancing extension like HTTPS everywhere - these kind of things typically have exceptions that allow you to disable them for given websites. You can run Firefox in safe mode (with all extensions disabled) to confirm that the behaviour you don't like is the product of an extension. -- Finlay McWalterჷTalk 00:18, 13 August 2012 (UTC)

It worked..... That was fast, thank you. 190.158.212.204 (talk) 00:27, 13 August 2012 (UTC)

Ummm, I disabled all my extensions and quited safe mode, it started using https again, what can cause this? 190.158.212.204 (talk) 00:31, 13 August 2012 (UTC)

You may have to enable extensions and plugins one-at-a-time until you figure out which one it is that's "helping" like this. If you're like me you probably have a dozen or two to wade through ;( It's probably one of the security-type ones: perhaps the toolbar associated with an anti-virus product, for example. -- Finlay McWalterჷTalk 00:35, 13 August 2012 (UTC)

Note that if I understand the OP correctly, they disabled all their extensions and ran it without any extentions enabled (but not in safe mode) but it still uses HTTPS. This suggests an extension is not causing the problem but for some reason safemode fixes it, I suspect the bugzilla below describes the problem. If so the solutions seem to be either change browser, or delete all https variants of the site from the history. Nil Einne (talk) 20:19, 13 August 2012 (UTC)

What extensions do you have installed, and at which site(s) are you having these problems with images loading slowly, etc.? There are pretty good reasons to prefer https in general. -- BenRG (talk) 16:53, 13 August 2012 (UTC)

Actually, Firefox 14 introduced this "feature". Here's the bugzilla report. From what I can see, they don't seem in any hurry to change it back. Another possible reason for you being forced onto https would be if the site was SPDY enabled. To turn this off, go to about:config in the address bar, search for network.http.spdy.enabled and change it to false. In my test just now this worked in preventing Firefox from forcing a https connection 92.233.64.26 (talk) 17:13, 13 August 2012 (UTC)

Yes, it did the job. Apparently!! I had to force http using a proxy that only supports http. 190.158.212.204 (talk) 21:31, 13 August 2012 (UTC)

Demonoid

Whatever happened to http://www.demonoid.me/ ? 124.253.63.168 (talk) 06:37, 13 August 2012 (UTC)

They were raided and shut down; the Demonoid domains have been put up for sale. --Lexein (talk) 07:00, 13 August 2012 (UTC)

I ask myself why a government, in the case the Ukranian, needs to launch a DDoS. Wouldn't it be easier to send the police and close the server, even if you only have a ridiculous reason to that? Comploose (talk) 14:22, 13 August 2012 (UTC)

What? The link which isn't exactly friendly to the Ukranian government, doesn't even hint that perhaps they were involved in the DDoS or the hacking that allegedly followed. Nil Einne (talk) 20:24, 13 August 2012 (UTC)

What what? I didn't say the link say that. I know that the Ukranian government is being accused of the DDoS, probably to deplete Demonoid-backers from funds. Maybe I should have respected the presumption of innocence, and said "possible the Ukranian government." Comploose (talk) 21:12, 13 August 2012 (UTC)

But none of the links provided thus far make the accusation, if you're going to bring random claims in to the discussion which no one else has mentioned yet, it would be best if you bring sources to back it up, this is the RD. Or else make it clear it's your own random thought not something actually discussed in sources (i.e. offtopic) or at least if the thing really did appear in sourced but you can't be bothered linking to them say something to make this clear, particularly when sources have already been provided (sources which would seem conducive to such ideas) which do not discuss the random things you're now bringing in to the discussion. Nil Einne (talk) 19:29, 14 August 2012 (UTC)

Glade Interface Designer and Python with PyGTK~(or whatever)

Is this combination somehow strange for designing GUIs? All the tutorials that I find are kind of +5 years old, and I wonder if everyone is simply using another route to design platform independent GUIs for Python programs (which is my intention). Comploose (talk) 13:06, 13 August 2012 (UTC)

It's a perfectly sensible option to just construct the UI with code yourself. Most of the python-gtk utilities shipped with Debian/Ubuntu seem to work this way. -- Finlay McWalterჷTalk 13:34, 13 August 2012 (UTC)

For general platform independence, you may consider not using a client gui toolkit, but building the app on a lightweight web framework like web.py running a local web server, and doing the GUI in HTML, CSS, and JavaScript. It's about the same degree of work as doing it in GTK or QT, and you can build a pretty rich UI with a toolkit like Dojo or jQuery. One advantage is that, if you later decide you want it to be network accessible (e.g. remote control from a cellphone) then the GUI is ready for that. -- Finlay McWalterჷTalk 13:59, 13 August 2012 (UTC)

Sound like a good idea. I'll take a look at Dojo and JQuery. Comploose (talk) 14:17, 13 August 2012 (UTC)

Best way of passing text/html to JavaScript from php

What could be the best way to store text, or to give text/html to javascript, Should I put them in css hidden <textarea> tags?? or encoding everything?, Thanks 190.60.93.218 (talk) 13:23, 13 August 2012 (UTC)

I'd have a separate resource (still generated by php) and have the javascript pull that with a XMLHttpRequest. Personally I'd encode it in JSON rather than XML and use the ready-made stuff in frameworks like jquery to decode that JSON. The great advantage of this is that you can have the javascript periodically refresh just the data (and then make changes to the page accordingly) without having to re-pull the page, and crucially without refreshing the page. -- Finlay McWalterჷTalk 13:27, 13 August 2012 (UTC)

I'm not sure there is one "best way" — it really depends on what you're trying to do here. Finlay's suggestion is a good one but requires you to re-write your Javascript and perhaps your PHP to make use of this option. Hidden TEXTAREAs are probably the worst way, though — you're relying on CSS compliance not to have your page fall apart from a semantic point of view, which is not a good way to do things (there are lots of good reasons that a user may be overriding your stylesheet settings). If you need hidden storage space, use INPUT TYPE=HIDDEN or just big Javascript string variables. --Mr.98 (talk) 13:33, 13 August 2012 (UTC)

How can I back up my mp3 collection to an external harddrive?

I have a Western Digital hard disk that I'd like to put my mp3s onto. I have been doing this manually so far but I'd just like a peice of software that searches for new folders I've added or changes to existing files without having to back up all the files from scratch each time. Preferably free software. Any pointers? — Preceding unsigned comment added by 77.100.75.68 (talk) 20:50, 13 August 2012 (UTC)

List of backup software ¦ Reisio (talk) 21:09, 13 August 2012 (UTC)

Robocopy Mitch Ames (talk) 11:29, 14 August 2012 (UTC)

Problem with serialising time stamps to XML in C#

I ran into a pretty difficult problem at work. We are developing a .NET application in C#, which sends SOAP messages to our customer's web service (which is beyond our control). Part of the SOAP message includes time stamps serialised in the ISO 8601 format, in the form "YYYY-MM-DDTHH:MI+NN", for example "2012-08-13T23:44+03". This serialisation is specified with an <xsd:element> node in the web service's WSDL description, with a type designator of "xs:dateTime".

The problem is this: When a transition from Daylight Saving Time to normal time occurs, our system provides the following kind of time stamps:

2012-10-28T03:00+03
2012-10-28T04:00+02
2012-10-28T05:00+02
2012-10-28T06:00+02

Our customer wants the change in the UTC shift to occur one hour later, such as:

2012-10-28T03:00+03
2012-10-28T04:00+03
2012-10-28T05:00+02
2012-10-28T06:00+02

I can't figure out how to do this. The serialisation to XML in the SOAP message occurs in the .NET internal libraries, I only get to feed a System.DateTime object into a pre-generated proxy class, and then the whole serialisation and SOAP message sending happens via a single method call to the .NET internal libraries. I have tried to approach the problem by creating a custom TimeZoneInfo object, which is set to 3 hours ahead of UTC with no DST change rules, and supplying the "2012-10-28T04:00+02" time stamp converted to this time zone instead. This resulted in the following:

2012-10-28T05:00

That it's one hour too late isn't the problem, I can fix that with a single method call. The problem is that it doesn't have any "+NN" information after it. Is there some way to force this to be appended, when I only have control over the DateTime object and not the serialisation code? I do have access to the source code of the pre-generated proxy class and the WSDL description on our end if that helps. JIP | Talk 20:52, 13 August 2012 (UTC)

Can't you just add in a kludge where you check for any timestamps in the one hour range you are looking for, and change them by an hour ? While you're at it, your program can add in the +NN info, too. I'd normally say it's a bad idea to fake the time like this, but, it seems, you've already decided to do that by changing the time for an hour. But, whatever kludge you put into effect should either be removed after the time change, or should be made to work for all future time changes, too.

However, this entire requests seems rather questionable to me. If you have the authority to refuse, you should. This seems to risk major problems for very little benefit. If forced to do it, be sure you can document that management forced you, in case there's a problem.StuRat (talk) 21:16, 13 August 2012 (UTC)

I'm confused. Your first list jumps directly from 03:00+03 to 04:00+02, which is a difference of two hours. The second list skips a different hour. Are you deliberately skipping one hour, and the customer is asking you to skip a different hour? Also, the DST-to-normal transition usually goes from 2:59 to 2:00, which means even your 03:00+03 is wrong. It should be 02:00+03, 02:00+02, 03:00+02, ... Please clarify what the customer actually wants. -- BenRG (talk) 01:10, 14 August 2012 (UTC)

I don't remember the exact output, I was writing from memory. But the essence is the same - the transition from +03 to +02 comes automatically when DST stops, but our customer wants it to happen at a different hour. I think part of the problem is that the hour our customer wants to be reported (2012-10-28T04:00+03 in my example above) doesn't even really exist. So merely shifting the time stamps by adding or removing hours won't fix the problem, the transition from +03 to +02 will happen at the same time anyway. User:StuRat said: "While you're at it, your program can add in the +NN info, too." But how can I do this? JIP | Talk 04:58, 14 August 2012 (UTC)

I'm talking about creating a fake time in a character string, where you can change it to say whatever time you want it to be, real or imaginary. StuRat (talk) 07:07, 14 August 2012 (UTC)

What's the reason for your customers request? The only reason I can think of is they are in a different time zone and having yours and theirs dst change coincide so the time difference stays constant is the easiest option... Ssscienccce (talk) 12:10, 14 August 2012 (UTC)

I managed to solve the problem by changing the corresponding field I need to set in the pre-generated proxy class from System.DateTime to System.String and then generating and supplying the ISO 8601 representation by hand. I didn't need to change the WSDL at all. I tested sending a request to our customer's web service and it seemed to work OK, hopefully tomorrow I'll hear from them if it worked. JIP | Talk 15:55, 14 August 2012 (UTC)

So, did it work ? StuRat (talk) 04:42, 17 August 2012 (UTC)

August 14

Audio file creation

How can I create an audio file of a phrase? Let that phrase be "Best in the World". Sunny Singh (DAV) (talk) 13:46, 14 August 2012 (UTC)

Record it from a microphone? Use a text-to-speech engine? http://www2.research.att.com/~ttsweb/tts/demo.php? ¦ Reisio (talk) 17:54, 14 August 2012 (UTC)

Remote pinging

I need to ping ~10 ip addresses 24/7, and this needs to be done remotely (ie not from my own connection). It would need to send only one ping every minute, but must continue 24/7 unattended. I have been unable to find any websites offering such a service for free (many offer it for a price, and some offer a free version but only for 1 ip address at not are the frequency I need)

Is is possible to write a php script which can do this natively (ie without calling any OS specific programs like ping.exe), and then host it on a free webhost?

I have already written a Windows batch script which does what I need, but finding a free Windows host is not easy, and while I could of course just run it on my own computer the results would not be useful to me because I am trying to diagnose a local ISP network error and when it happens I lose all internet connectivity.

Thanks for your help 92.233.64.26 (talk) 15:22, 14 August 2012 (UTC)

I wonder if codepad can be any help. I haven't tried this site, so I don't know its limitations, but it looks like you could write some code in, say, python, to ping your addresses for 24 hours, and then run it there (with "private" ticked, presumably).  Card Zero  (talk) 15:31, 14 August 2012 (UTC)

At least in python, codepad does not support the ICMP library nor RAW sockets. -- Finlay McWalterჷTalk 16:01, 14 August 2012 (UTC)

It's worth noting that only root can ping. Your options, then, are running the usual /bin/ping program, which is setuid root, or running your Python script as root. I doubt the latter is allowed on any free webhosting services! Marnanel (talk) 04:56, 17 August 2012 (UTC)

Will this RAM fit (and work) in this motherboard?

Hi there,

I have 2 computers, both DELL, both have a 0G1548 motherboard. Both have (according to SIW) 2 RAM slots and a maximum capacity of 1024MB (I don't know if that's in total for each slot, or total for each machine). Both computers have a stick of DDR (PC2700) 256MB 166MHz in each slot, giving each computer 512MB of RAM.

I've been given 2 sticks of RAM. The first is a 1GB stick of DDR2-533 DIMM and the second is a stick of 512MB 1Rx8 PC2 4200U - 444 - 12 - ZZ.

I'd like, if possible, to increase the RAM in one or both computers - will either of my 'new' RAM sticks fit/work in the new machines? If so, what's the best combination? Should I put the 1GB in one machine and the 512 in the other (with a 256 in the second slot)?

Any and all advice gratefully received, especially if it's in words of one syllable.

thanks. — Preceding unsigned comment added by 2.97.223.11 (talk) 16:55, 14 August 2012 (UTC)

For starters, the limit could be real or it could be unnecessarily implemented by an outdated BIOS or an economy version of a certain operating system—worth a check. Regardless, you might be able to get dirt cheap RAM (it's mostly a crap shoot what will be particularly cheap at any given time) at http://crucial.com/ (will also know what the limit likely is) or the like. Keep in mind (when you consider how much time / money you're going to spend on this) that an entire new computer in the USA with 2-4GB of RAM (>2GHz proc and even dedicated graphics) can be had for around $200-300 (maybe an extra $50 for a laptop), . ¦ Reisio (talk) 18:03, 14 August 2012 (UTC)

If the RAM fits it should work, and it won't hurt anything to try. However, it sounds like you've been given 2 sticks of DDR2 and your PCs take plain old DDR, so they won't fit. 209.131.76.183 (talk) 19:53, 14 August 2012 (UTC)

nVIdia Output Specification

Heya,

I've got a bit of a question regarding my nvidia 540m graphics card. I can't seem to find any specifications online that tell me whether or not it can output a RGB component signal if adapted from a HMDI or VGA port. I'm wanting to find this out before I go about buying an adapter. Thanks in advance, Sazea (talk) 17:45, 14 August 2012 (UTC)

Like for an old TV/system? Worst case you might need a little box to convert the signal to TV-out, they can be had for $20-30 on newegg, amazon, etc.. ¦ Reisio (talk) 18:08, 14 August 2012 (UTC)

The worst case as I see it would be buying a simple adapter for the two, finding out it doesn't work, then buying a box. I'm not sure if there's information anywhere that says whether or not a specific graphics card can output a specific signal or whether it's up to the hardware, software or both to convert it. Adapter retailers seem to think that this information exists, and I'm interested to know if it does. But I will keep a converter in mind, should it not be able to. Sazea (talk) 21:42, 14 August 2012 (UTC)

Not enough room to copy onto a hard drive ... but there IS enough room.

I need to copy a 28GB folder (it is an ArcGIS geodatabase that appears within ArcGIS as one .gdb file but is really a folder of many files) from a portable hard drive to my computer's hard drive. The latter says it has over 100GB of free space, and it is a distinct physical drive, rather than a partition. The process keeps failing because "there is not enough space" on the destination. But there is. Honestly. Why does this happen and what should I do? Tom Haythornthwaite 19:18, 14 August 2012 (UTC) — Preceding unsigned comment added by Hayttom (talk • contribs)

Does the directory you're trying to copy have sparse or file system (e.g. NTFS) compressed files? Nil Einne (talk) 19:26, 14 August 2012 (UTC)

BTW I forgot to mention on Windows you should be able to tell if this is likely to be a problem by comparing the size and size on disk as recommended by 92 below. (Clusters could be a problem although it would have to be fairly extreme to be the only problem given the sizes involved.) Nil Einne (talk) 21:23, 14 August 2012 (UTC)

The standard Windows (assuming you're using Windows, you didn't say) copy system is quite bad, I would recommend using FastCopy for anything over 1GB. Also, depending on how many files you're talking about and how small they are, it is possible that their "size on disk" is more than their actual size due to the way file systems allocate clusters. 92.233.64.26 (talk) 19:55, 14 August 2012 (UTC)

You might want to try copying a few files at a time. This will do two things for you:

1) If the copy function is just defective and not able to handle a job that big, you can bypass that problem.

2) If there is a corrupted file which the system thinks is larger than it really is, this will help you identify that file. StuRat (talk) 20:49, 14 August 2012 (UTC)

This might be reaching here but is it possible that the OP will run out of inodes if the copy goes through and is therefore stopped before it can begin while giving a misleading error message? I'm aware that inodes are used on *nix systems. Does Windows have something similar to inodes? Dismas|^(talk) 20:56, 14 August 2012 (UTC)

NTFS's MFT records are similar to inodes, but the MFT grows as needed so it's impossible to run out. FAT had a fixed-size root directory which could fill up and produce a disk full error, but FAT32 and NTFS don't have that problem. Filesystem corruption is a likely culprit—run chkdsk or fsck. -- BenRG (talk) 06:30, 15 August 2012 (UTC)

• As others have suggested, it is impossible to answer this question usefully without knowing your operating system. It would also be helpful for you to give the specific wording of the error message you received. Looie496 (talk) 04:13, 15 August 2012 (UTC)

[OP] Sorry... Windows 7. Our IT person did something to the destination drive - I heard him mumbling about FAT - and then the copy worked. — Preceding unsigned comment added by Hayttom (talk • contribs) 15:36, 16 August 2012 (UTC)

Glad to hear it. I'll mark this Q resolved. StuRat (talk) 23:37, 17 August 2012 (UTC)

Resolved

traceroute

I did a traceroute to the site mempsimoiria.datnode.net and its domain name does not match the dns records and it not even a valid domain name.

"debian.more.like.plebian.amirite"

Can you explain this to me please? 91.122.82.15 (talk) 20:44, 14 August 2012 (UTC)

There are address records for looking up IP numbers, in this case 206.195.167.199.in-addr.arpa name resolved to debian.more.like.plebian.amirite. The forward lookup does not match the reverse lookup. Traceroute looks up the IP numbers it comes across by default. Use -n if you don't want to see names resolved for the numbers. Graeme Bartlett (talk) 22:18, 14 August 2012 (UTC)

Plebs.... :p 190.158.212.204 (talk) 15:46, 15 August 2012 (UTC)

Help me find a FB app: Matches me to a list of users with the most mutual interests.

I must have "liked" over 1,000 fanpages by now. If there's an app out there that matches other users of that app with whatever apps I like, then ranks me against other users with the most mutual interests, then I would like to subscribe to said app because it could quite possibly help me find the love of my life.

Now, what Facebook app does something that fits anything close to my description?

If this can't be on Facebook, what is the best off-FB app that does this? Thanks. --70.179.170.114 (talk) 21:51, 14 August 2012 (UTC)

There are lots of online dating sites that try to match people with mutual interests. Facebook is not really set up for this for privacy reasons. There are quite a few Facebook dating apps, I believe, but I'm not sure any of them can correlate by mutual "liked" interests — there may be security issues with such a scheme. --Mr.98 (talk) 13:05, 15 August 2012 (UTC)

I think I remember seeing something like this on somewhere like Late Night with Jimmy Fallon, but I cannot for the life of me remember its name to see if it does what you want or if it's available to the public yet. It started with "Air", I think. - Purplewowies (talk) 16:49, 16 August 2012 (UTC)

August 15

I am Naveen Ganesan

how i insert an image in user page...? pls anyone help me in clear steps....? — Preceding unsigned comment added by Naveen Ganeasn (talk • contribs) 03:28, 15 August 2012 (UTC)

Please ask this question at the Help desk, WP:HELPDESK. That is the place for questions about how to use Wikipedia. Looie496 (talk) 04:09, 15 August 2012 (UTC)

Regex and sed

I have an html file that has a table in it. The table has a number of entries such as "S1234A56" or "S123AA45". They all start with S, have 3-4 digits, 1-2 letters, and a final 2 digits. They are all exactly 8 characters long. I need to change all of them so that the string is put into a URL. I was hoping to just use a quick Perl script on my Linux machine to make all the substitutions but I'm stuck on how to write the sed command. Will I have to use escapes for all the non-alphanumerics in the URL? Or can I wrap it in something that will pass it without escapes? Right now, I've got something along the lines of

sed "s%S\d\{3,4\}\a\{1,2\}\d\{2\}%<a href="https://www.someurl.com/foo.pl?id=MYSTRING>MYSTRING</a>%"

And replacing MYSTRING with the regex from the first part. The reason I'm using % for the delimiter is that it doesn't appear anywhere in my URL.

So, where am I going wrong? Is there an easier way that doesn't involve sed? Thanks for any help, Dismas|^(talk) 04:15, 15 August 2012 (UTC)

From my initial investigation sed does not recognise \d as meaning a digit. My version of sed thinks that is just a letter d. Therefore you will need [0-9] instead and you need the \( to select the string to replicate - so

$ sed 's%\([0-9]\{3,4\}[A-Za-z]\{1,2\}[0-9]\{2\}\)%<a href="https://www.someurl.com/foo?id=\1">\1</a>%g'
1234TT77
<a href="https://www.someurl.com/foo?id=1234TT77">1234TT77</a>

Thanks! That worked perfectly! There were about a half dozen that didn't fit the scheme because they were labeled things like LOANER1, LOANER2, etc. But they were easy enough to do by hand. I'd have hated to do all the rest by hand since there were a few hundred. Thanks again! Dismas|^(talk) 10:07, 15 August 2012 (UTC)

zero indexing of arrays

Hi, this is kind of a quirky one, but I'm doing some massive array storing (and manipulating, but mainly storing) using Strong's Concordance. All entries are stored with a number, and the numbers start at 1. As a result, I'm using an array where the first (ie, the "zeroeth") entry is blank, so the array index number matches the Strong's concordance number. Is this considered good coding practice? Is there some set of rules stating when you should do this, when you should avoid it, and when it's basically six of one, half a dozen of the other? IBE (talk) 07:24, 15 August 2012 (UTC)

There's nothing wrong with it. What you start your array with — heck, what keys you use in general, since that's entirely flexible with associative arrays — is just a matter of convention and keeping things internally consistent. Just make it clear that you're using one-based indexing and all is well. Depending on your language, it's probably absolute bestest practices not the initialize the zeroth array entry anyway (why use extra memory?), but really, it won't matter as long as you never try to do anything with it. --Mr.98 (talk) 13:01, 15 August 2012 (UTC)

I don't know why Mr.98 assumes you're using an associative array. I'm going to assume you're writing in C. Since you're using C, the advantage of having zero-based arrays is that (array identifier) + (index of element) = (address of element): see Array data type#Index_origin, and more at Zero-based_numbering#Advantages - another advantage is that you can use the modulus operator (%) to do certain array-navigating tasks conveniently.  Card Zero  (talk) 16:57, 15 August 2012 (UTC)

I'd say it has a minor whiff of code smell but it's reasonable in the situation you describe. Numerical Recipes in C follows a similar convention, so that the C programs use the same subscripts as the corresponding programs in the Fortran edition of the book (Fortran uses 1-based arrays). 67.122.211.84 (talk) 22:00, 15 August 2012 (UTC)

The code is in JavaScript, but for most purposes, simple array behaviour is much the same as in C, and the syntax is of course C-style. Yet js is such a messy language that it requires the programmer to watch his every step. I have function names almost as long as the screen, with information like fileNamePurposePrimaryInterfaceCreateListOfSuchAndSuch - all just to avoid confusing myself. Hence the concern about getting the array indexing as neat as possible - js is very good at allowing you to stuff up. I'll stick with the current system, but would be interested in further discussion. I don't have any need for accessing the address (I don't even know how to do it in js), and there is no modular arithmetic - it's just the big file of one dictionary, with entries numbered 1 to about 5400. Hence for this one big thing, it made sense - Strong's concordance numbers are a key part of Biblical scholarship, so I tend to think in terms of the number, and it would be hard to change. Still, I am open to persuasion - I've kept this kind of indexing out of every other part of the program, because I can see the danger. IBE (talk) 13:09, 16 August 2012 (UTC) Further point: I'm pretty sure it's an associative array - I don't know what a dissociative array would be. It's a standard array created by the Array() constructor in js. IBE (talk) 13:12, 16 August 2012 (UTC)

If you're using javascript, leaving gaps in the array is fine (apparently there's a gap of 100 entries in the middle of Strong's concordance anyway, so leaving entry #0 empty is insignificant beside that). I can't find a good reference for this, though. You can have a bad reference, if you like (i.e. what some guy on the internet says): [1] look at the reply to the second answer - "all JS implementations have 'efficient' implementations of arrays, at least they are substantially more efficient than normal objects. They all assume that a compact array is the norm, and a sparse array is uncommon, and for the reason optimise for 'normal' array usage." So your array should be compact, which is not the same as being completely free from gaps.  Card Zero  (talk) 14:48, 16 August 2012 (UTC)

Thanks to you all for the help, IBE (talk) 19:12, 16 August 2012 (UTC)

I usually prefer to start arrays at 1, even if that wastes the zeroth one. Reasons: the first one is 1, the second one is 2, the nth one is n. Bubba73 ^{You talkin' to me?} 20:22, 16 August 2012 (UTC)

Yeah, for javascript, don't worry about 1 or the gaps. 5400 is a small array by today's standards. Massive would be billions or at least millions. 66.127.54.117 (talk) 07:30, 18 August 2012 (UTC)

Variables in wikipedia

Are there any plans to support variables in wikipedia? Say, if I have a number which appears in several wikipedia articles and this number changes, ideally I would only edit it in one place, not in all articles where it appears. (I just updated Lists of National Treasures of Japan with three new designations and had to change numbers in several places.) Or would this feature be too complicated for the users? bamse (talk) 08:36, 15 August 2012 (UTC)

If you need help using Wikipedia, you'd be better off at the Help desk. Future plans for Wikipedia can be suggested and discussed at the Village pump. There appears to be a limited implementation of what you have in mind, known as Magic words - see also the MediaWiki 'Magic Words' help page. This seems too be only useful for things like current time and date, though. The text on the first page suggests that there's a server cost in calling the value of a variable, so it may be that having lots of variables that need to be queried for the current value each time a page loads (if that's how it works) would be prohibitively demanding on the servers. But you can make the suggestion at the village pump - I'm sure someone will be able to tell you exactly why the sky will fall in if it's adopted :-) - Cucumber Mike (talk) 09:48, 15 August 2012 (UTC)

You could also use templates, so for example a template called template:numberoftreasures and then on this page put your number. Then insert this variable with {{numberoftreasures}} However it does also make it more tricky to update and more likely a person will make a mess. Also if the page becomes too complex it may not render. Graeme Bartlett (talk) 10:57, 15 August 2012 (UTC)

Thanks for the replies. bamse (talk) 11:36, 15 August 2012 (UTC)

If you want an example of the "may not render", you can check out List of hard rock musicians (A–M) and List of hard rock musicians (N–Z). It was originally one list which I split into two. Part of the reason why it was me who did it was that when the article was brought to mine and other editors' attention, I was one of the few who could get it to render completely. The roughly 800 references were bogging it down. Dismas|^(talk) 18:30, 15 August 2012 (UTC)

I proposed a way to incorporate variables (birthdates, temperatures, stockprices) into MediaWiki without using templates, using a Facts tab instead, making it very easy for robots to maintain such data. Unfortunately the project doesn't seem very active. Joepnl (talk) 20:31, 15 August 2012 (UTC)

Address bar search (email id)

Like many other people I also search directly from address bar (Ctrl+L→Type→↵ Enter). Today I put an email id in address and presed enter and I got message "You are about to log in to the site "gmail.com" with the username "abcdef", but the website does not require authentication. This may be an attempt to trick you. Is "gmail.com" the site you want to visit?" – is this an expected behaviour? --Tito Dutta ✉ 09:12, 15 August 2012 (UTC)

Yes. If you use an URL with an "@" in it, it means, "try to log in as this user." It's a bit antiquated — it's not using Google's login, for example, but .htaccess authorization. This is usually only used for doing things like logging into servers, routers, or really quite old systems; it's rarely used for actual sites because the name and password are usually sent in the clear (that is, not encrypted in any way). The "tricking" aspect is because it used to be (in the mid-1990s) a common phishing tactic to obfuscate URLs this way. So you'd put in something like http://youractualbank.com?toomanyqueryvariablesforyoutonoticethatactuallywe'regoingto@myevilsite.com. It would thus be hard to see which site you're really visiting — that whole first part is just being passed as a "user name" to the actual site. So now browsers usually warn you if something like this is happening, because people rarely try to log in using this anyway. --Mr.98 (talk) 13:10, 15 August 2012 (UTC)

The above is basically what Safari gave me when I plugged in an email address. I got a warning saying that I was trying to access a potentially dangerous phishing site. Especially funny considering I used my work email address for the test.  :) Dismas|^(talk) 18:18, 15 August 2012 (UTC)

Except that the quoted URL actually works and lands you at 'youractualbank.com' instead of a phishing site :) Unilynx (talk) 19:57, 15 August 2012 (UTC)

Sorry, yeah. The description about phishing scams was closer to what I got. Dismas|^(talk) 20:23, 15 August 2012 (UTC)

Try it with quotes surrounding the address. ¦ Reisio (talk) 21:59, 15 August 2012 (UTC)

 Great! Quotes surrounding it a great idea! --Tito Dutta ✉ 13:18, 16 August 2012 (UTC)

Audio file on facebook

How to upload Winamp media file on facebook from computer? It is an audio file, not video file. Sunny Singh (DAV) (talk) 09:12, 15 August 2012 (UTC)

There are some apps like this, you can search in Facebook apps centre more. Also does it work when you try to attach it (in messages)? --Tito Dutta ✉ 09:15, 15 August 2012 (UTC)

PHP, Replacing Arrays

I have a php script that updates arrays after each execution. They are values that belong to a group, when the script is executed those variables may change to another group.. so I have group 1, group 2, group 3 & group 4. So when the php script is executed it gets more values (new values sometimes) and the group for each one. So if there are new values, it just appends them to the array, for the old values I need to remove them from the old group and move them for the new group. Take this example: There are 3 baskets with fruits already.

Extended content
$previous=Array ( 'Basket1' => Array ( 'berries', 'pineapple' ), 'Basket2' => Array ( 'red apples', 'Strawberries' 'melon' ), 'basket3' => Array ( 'avocado', 'peach', 'pear', 'green apples', 'banana' ) )

When the scripts run again it updates the info, with new fruits, or/and fruits in different groups, so I have create an array that contains the updated information+the old information...

Note:in this example there are 3 baskets in the real code there's actually a lot more arrays.

The thing is... I exactly don't know how to update the info... I could manually make a lots of 'ifs and for loops but it doesn't seem right, and is not extensible. I created this function to delete old values that appear on another groups (The fruit has changed bascket).

Extended content

function RemoveChangedValues($oldBasket,$secondOldBasket,$basket,$secondBasket){//whatever return Array( array_diff($oldBasket,$basket), array_diff($secondProxy,$forthProxy));//this returns an Array of the "old basket" and the "second basket" with the repeated values removed //later the both arrays (old and new) can be concatenated and then remove the duplicate values of each array... or.. that's the idea. }

The thing is that I can't find a way to easily loop through all the groups and call that function (other than writting lot's of if statements). Any ideas how this can be done? thanks! 190.158.212.204 (talk) 17:10, 15 August 2012 (UTC)

Can you expand on "When the scripts run again it updates the info, with new fruits, or/and fruits in different groups, so I have create an array that contains the updated information+the old information..." ? How exactly do you get the info telling you which fruits to add to each group, remove from each group, and move from one group to another ? An example would be good. StuRat (talk) 04:15, 16 August 2012 (UTC)

When the user submits some data, it sends information, it's converted into an array, I got the array from previous inputs, but I don't know how to merge the arrays. Is not actually 'removing' them it's just moving them, (removing then adding), you see if at the first time, I get 'apples' in the first group, then get the same item 'apples' but in the second group, then I would have to remove apples from the first group because it has moved to the second group. Is not anymore on the first group. The only thing the script gets it's fruits and their groups, I have to merge them with their previous results... — Preceding unsigned comment added by 190.158.212.204 (talk) 04:47, 16 August 2012 (UTC)

What I'm trying to get from you is the format the information is supplied to your script. Is it like this:

APPLES  -> BASKET1
PEACHES -> BASKET2
GRAPES  -> BASKET1

Or like this:

BASKET1 -> APPLES, GRAPES
BASKET2 -> PEACHES

Or something else ? StuRat (talk) 05:21, 16 August 2012 (UTC)

In any case, it would certainly help if you could refer to arrays by number, rather than names like "Basket3". I don't use PHP, so I'll use generic pseudocode. Does it support an array of lists ? If so, you could make that "Basket[3]", which would make loops work better. Something like:

FOR B = 1 TO HIGHEST_BASKET_NUM
  FOR N = 1 TO HIGHEST_FRUIT_NUM_FOR_BASKET[B]
    IF (BASKET[B].FRUIT[N] = CURRENT_FRUIT) THEN
      DELETE (BASKET[B].FRUIT[N])
    ENDIF
  ENDFOR
ENDFOR

If PHP doesn't support an array of lists, then you could just make it a two dimensional array:

FOR B = 1 TO HIGHEST_BASKET_NUM
  FOR N = 1 TO HIGHEST_FRUIT_NUM_FOR_BASKET[B]
    IF (FRUIT[B,N] = CURRENT_FRUIT) THEN
      DELETE (FRUIT[B,N])
    ENDIF
  ENDFOR
ENDFOR

(Note that my loops above start at 1, since I assumed the arrays start with the first element. If they start with a zeroth element, then the loops should start at 0.)

However, at some point this approach would become unwieldy, say if you have thousands of baskets each containing thousands of fruits, then this would take millions of checks to find any given fruit. In this case, you might want to create an alphabetized index, which would store each fruit, along with the basket it occupies. You could then do a binary search to find the fruit in the index, and that would give you the basket. (You could also index it's position in the basket, but then you'd need to update this whenever any lower fruit was deleted, assuming you repack the baskets to take up empty spaces.) The index would still need to be updated when a fruit is moved, which would be fast, or when a fruit is added, which would be slow.

To give more specific advice, we'd need to know the max number of baskets, max number of fruits in each basket, number of updates expected, etc. StuRat (talk) 05:46, 16 August 2012 (UTC)

Monitor problems

Hello! I'm having a strange problem with my monitor. Whenever I turn it on after not using it for a while (i.e. overnight or when I return from work), it does one of these: 1) Screen flickers rapidly on and off for a few seconds and then stays on like normal; 2) Flickers the screen on once, then immediately off again, and I have to push the on switch twice (on -> off -> on) for it to try again--this can happen up to four times before behaving normally; or 3) A combination of #1 and #2. Once the screen stops behaving strangely and is in the "on" state, it behaves normally and experiences no more problems for as long as I keep it on. Any ideas as to what is causing this? -- 143.85.199.242 (talk) 17:34, 15 August 2012 (UTC)

LCD? CRT? ¦ Reisio (talk) 21:56, 15 August 2012 (UTC)

-- Sorry; a Samsung LCD, SyncMaster 226BW. (I am the IP.) -- Tohler (talk) 04:00, 16 August 2012 (UTC)

Sounds like a classic cold start problem. It might be that the temperature is the problem, and it needs to warm up a bit for the thermal expansion to bring two components into constant contact with each other. Does this also happen if it goes into standby mode ? If not, then just leave it on standby. If standby mode doesn't fix it, then you're down to leaving it fully on all the time, putting up with this annoyance, or replacing it. I doubt if it would be financially viable to have it fixed, unless it's a very expensive monitor. StuRat (talk) 04:07, 16 August 2012 (UTC)

What are the consumer protection law (aka lemon-laws) like in your area? (I think you are in Arizona, US) If the monitor is still covered by them, I'd claim under those. The symptoms sound like a fluorescent lamp failing to start (ballast/starter on its way out). Do you know what kind of backlight the monitor uses? If you put an image with large black and white areas on it up, and then turn the monitor off, and the back on without it starting correctly, can you just make out the black and white areas? CS Miller (talk) 14:55, 16 August 2012 (UTC)

Csmiller: I created an HTML file with a black BG, containing tables with white BG interiors and black text within. All of it was completely visible as the monitor flickered.

StuRat: I never use standby mode; I always shut my monitor off when I'm not going to be using it for a long while.

I neglected to mention that I have been using this monitor since mid-2010 with no problems; this began within the past month. -- 143.85.199.242 (talk) 15:29, 17 August 2012 (UTC)

Well, try standby mode to see if it fixes the problem. StuRat (talk) 15:38, 17 August 2012 (UTC)

Help with Changing Youtube Email

I have a rather annoying problem and I hope you don't mind helping a non-tech savvy person like me out. I have a G-mail account that I use for private email with my personal name, and I have linked it with my Youtube account. I want to set up a new G-mail account with the same name as my Youtube account so that I can give it to people so I can talk with them without giving my personal name out. However, when I tried to set up the G-mail account, it won't let me because it says someone else has that name (Probably because my Youtube account has that same name.) What can I do to set up the E-mail account I want? Rabuve (talk) 20:13, 15 August 2012 (UTC)— Preceding unsigned comment added by Rabuve (talk • contribs) 18:36, 15 August 2012 (UTC)

I wouldn't get too optimistic, but take a look at http://support.google.com/youtube/bin/answer.py?hl=en&answer=183819 ¦ Reisio (talk) 21:54, 15 August 2012 (UTC)

And the second part, you can not sign up for that Gmail address too. I have some suggestions still– do you have lots of videos in the channel? 2) have you tried Google Apps for the channel's name (Google Apps is free, but you need to have the domain), is the domain name available? --Tito Dutta ✉ 13:22, 16 August 2012 (UTC)

I tried setting up a slightly diferent email account (my youtube name plus a few numbers) but now it won't let me add it as an alternate email. Any advice? Rabuve (talk) 18:39, 16 August 2012 (UTC)

How much would this storage server cost?

A recent article at MBNet.fi mentioned this storage server, saying it could hold a maximum of 32 terabytes and prices start at 400 €. 400 € seems awfully low for 32 terabytes - that's only a bit more than 1 cent per gigabyte - so I'm guessing it's for the server only, without any disks. How much would such a server fully laden with 32 terabytes of storage cost? JIP | Talk 21:12, 15 August 2012 (UTC)

It has 4 bays each for a single SATA3 disk; the list of compatible disks has at most an Hitachi 4TB disk. So that's 16TB. That disk, an Hitachi-HGST Ultrastar 7K4000, retails in the UK for about £450. I don't see a listing for a compatible 8TB disk, which would need to bring it up to 32 TB. I imagine Hitachi et al will have an 8TB in the works; you can extrapolate a bit and get maybe £1000 for that, when it's released. £4000 is about €5000. -- Finlay McWalterჷTalk 21:46, 15 August 2012 (UTC)

Disks are pretty obviously not included in that price. 4TB drives are still exotic (and reportedly not that reliable) and 8TB drives are probably still at least a couple years away. Note also you shouldn't set up a disk array for any important read-write usage without some type of RAID. With four 4TB drives, you'd get either 8TB (RAID-1 or RAID-10) or 12TB (RAID-5) of usable capacity. 4TB Hitachi Deskstars are around 270 USD (jr.com, newegg.com) last time I looked, and the faster and maybe more reliable Ultrastars are around 450 USD. 2TB drives are somewhat less expensive per GB. If you really want a low budget 32TB array, I'd suggest a general purpose storage server (supermicro.com e.g.) rather than a dedicated NAS these days. 67.122.211.84 (talk) 22:09, 15 August 2012 (UTC)

Why doesn't Firefox automatically update on Linux?

Why doesn't Firefox automatically update on Linux? It does on Windows. At work, Firefox has happily updated itself to at least version 11. At home, I have version 4, and even that only because I configured the Linux update manager to be able to download it - otherwise I would still be stuck with version 3. Even the Mozilla Firefox web site says Firefox can be configured to automatically update itself by selecting "Automatically check for updates for Firefox" at the "Updates" tab in the "Advanced" preferences. But there's no such option. There's options for Add-ons and Search engines, but not for Firefox itself. This is in direct contradiction to the screenshots shown on the Mozilla Firefox web page. Does Mozilla have some sort of issue against Linux or is it just a problem with my distribution (Fedora 14 Linux)? JIP | Talk 21:20, 15 August 2012 (UTC)

Linux updates to Firefox usually come from the distribution's update system (locally that's where they should come from, if that's where you got Firefox from in the first place). Fedora 14 is "release no longer supported", so Fedora won't be packaging new versions of anything. -- Finlay McWalterჷTalk 21:29, 15 August 2012 (UTC)

So if I want to update to the newest version of Firefox, do I either have to update the whole operating system, or try to install the latest version of Firefox by hand, and struggle with version conflicts of shared libraries for weeks before I get it to even start up? Or is there an easier way? Updates to Firefox on Windows seem to be coming from Mozilla itself (I can't imagine Microsoft providing them), so why can't this happen for Linux too? JIP | Talk 21:34, 15 August 2012 (UTC)

You should update your OS (Fedora) to the latest stable version, and regularly update it from here on out. You are missing a lot of bug fixes and security patches, just for starters. ¦ Reisio (talk) 21:49, 15 August 2012 (UTC)

Mozilla has no control over third-party Firefox builds on any platform. It's the responsibility of the maker of the custom build to update it, and they don't tend to do that at nearly the rate of Mozilla's official builds. If you install Firefox from mozilla.org you should get automatic updates from Mozilla. There's just one official Linux binary build there; I assume it comes with its own versions of all relevant libraries to avoid .so hell. -- BenRG (talk) 21:43, 15 August 2012 (UTC)

Yeah Mozilla provides Linux binaries, but you'd be a fool to actually use them. :) ¦ Reisio (talk) 21:48, 15 August 2012 (UTC)

Linux systems have package managers, which typically give you the ability to install/remove/update any and all software uniformly, at any time you choose or schedule. There is one manager (per distro), and it works with everything.

Windows does not have a package manager. Each application is responsible for its own update method. There is little to no organization or interaction between them. Each package is responsible for making its own installation system, uninstallation system, update system, and for installing any other packages it needs to work (and checking if they're already installed or not, etc.), etc..
¦ Reisio (talk) 21:46, 15 August 2012 (UTC)

You've chosen a Linux distribution with a deliberately short maintenance window - as the article says "With 6 months between releases, the maintenance period is a very short 13 months for each version". If you need to stay on a release for years, and have it maintained, Fedora is the wrong choice. Ubuntu LTS is supported (meaning you get security patches, not new versions of stuff) for five years; Red Hat Enterprise Linux for longer still (if you pay). -- Finlay McWalterჷTalk 21:58, 15 August 2012 (UTC)

But in general I would say that if your plan is to avoid updating as long as possible, your plan is truly flawed. You should be updating far more frequently than once every 13 months. Most distros have automated update options available these days — use it. ¦ Reisio (talk) 22:03, 15 August 2012 (UTC)

I started using Linux with Red Hat, and switched to Fedora when Red Hat split up to Fedora and Red Hat Enterprise Linux. So I could say I've practically always been using Fedora. Perhaps a switch of distributions would be in order? Ubuntu is still Linux, so I could live with that. I don't want to switch to Microsoft Windows or buy a Mac instead. But would switching to a different distribution require a complete re-install of the entire operating system? Would old binaries from Fedora 14 still work, or would I have to re-install all the programs too? I assume Ubuntu can read EXT4 partitions all OK, so I won't have to reformat my personal data partitions. But really all this seems to be a bit too much just to update Firefox. JIP | Talk 22:05, 15 August 2012 (UTC)

Firefox is the least of your problems; your system, and all its applications, is no longer getting security updates. You have a bunch of vulnerabilities which will never be patched. You shouldn't want to somehow get those old binaries to run on a new system; they're still unpatched. For production systems, where you don't want to update the system every six months, you'd use RHEL, Oracle Linux, Ubuntu LTS, and the like. For a desktop machine of your own, for general purpose use, you want to keep on the latest, or latest but one, release of your dist. There's nothing at all wrong with Fedora, but no-one should be running Fedora 14. -- Finlay McWalterჷTalk 22:11, 15 August 2012 (UTC)

^ What he said. ¦ Reisio (talk) 22:19, 15 August 2012 (UTC)

Google Drive

How do I download the Google Drive app for my PC? The instructions say

Go to http://drive.google.com.

Click the Download Google Drive for your PC button.

but I don't see any such button. Rojomoke (talk) 22:11, 15 August 2012 (UTC)

I see the link on the left hand side pane. What operating system are you using? I'm pretty sure there's no Linux client, so if you are using that to access the site, you may not get the link. - Akamad (talk) 22:32, 15 August 2012 (UTC)

Try https://tools.google.com/dlpage/drive?pli=1#eula. Moondyne (talk) 02:59, 16 August 2012 (UTC)

For me, the link said something like "Free 5GB" and it was in the upper right. Though your mileage may vary. For instance, I already have a Gmail address and a Google Docs account, so I already had the predecessor to GDrive and was signed in to my account. Once I clicked on the button, I was given the chance to download the syncing software for my PC. Dismas|^(talk) 03:10, 16 August 2012 (UTC)

• Information needed: Operating System! You'll not see the download link if you are a Linux user! If you are using Windows or Mac, above information should help! --Tito Dutta ✉ 13:26, 16 August 2012 (UTC)

THe OS is Windows 7, and I do already have a Gooogle account. But logged in or not, I still can't see the links you've given. However, the URL Moondyne gives worked fine. Thanks to all. Rojomoke (talk) 20:02, 16 August 2012 (UTC)

ZFS, heterogeneous storage media and heterogeneous access patterns

I'm looking at buying a solid-state drive to use alongside the hard drive in my Windows 7 gaming workstation, and using FreeNAS or ZFSguru to combine them into a ZFS striped vdev. (I don't need redundant storage.) It occurs to me that the optimal striping pattern will vary between (and sometimes within) files with the frequency of reads versus writes and random versus sequential access, because these affect the two devices' relative overall speeds. Can ZFS monitor these characteristics at the file level, and/or at the byte-range level for gigabyte-plus files, to optimize the striping? Can it predict them for new files based on e.g. data type and folder path? Also, do similar capabilities exist for compression and deduplication? NeonMerlin 23:05, 15 August 2012 (UTC)

That is massive overkill. Just buy a high quality SSD for your system files and other stuff that needs speed, and some regular HD's for your media archive. Make sure to check the 4k random iops in the SSD specs since some not-so-good SSD's are crappy in that important department. 67.122.211.84 (talk) 18:43, 17 August 2012 (UTC)

August 16

MediaWiki: get URL params

Question moved to Village Pump. 178.216.128.99 (talk) 06:53, 17 August 2012 (UTC)

SATA III hard drive in a SATA II interface?

Will a SATA III (three) hard drive work in a SATA II (two) interface? JIP | Talk 18:30, 16 August 2012 (UTC)

As our Serial ATA mentions, there isn't such thing as SATA III. It doesn't really mention but there isn't really such thing as SATA II [2] either. The term SATA II is usually used to refer to the 3 Gbit/s interface speed and SATA III a 6 Gbit/s interface speed but the rev 2.0 of SATA included a number of enhancements beyond the speed increase, similarly rev 3.0 of SATA; however many hard disks may include some features supported by the new revision (particularly the increased interface speed) but not all so it's difficult to answer without knowing precisely what you're talking about. (AFAIK, SATA is supposed to always be backwards and fordwards compatible between revisions although as our article hints at, in practice problems sometimes occur.) Nil Einne (talk) 18:52, 16 August 2012 (UTC)

I was mainly interested in buying this hard drive. It says "SATA III" on the page, however I'm fairly sure my computer's motherboard only has a SATA II (SATA rev 2.0?) interface. JIP | Talk 19:26, 16 August 2012 (UTC)

According to [3], that drive has 6 Gbit/s transfer speed which is probably what that vendor means by 'SATA III'. According [4], the drive has a jumper to limit it to OPT1/1.5 Gbit/s which suggests 2 things. 1) At the time designing the drive, WD hadn't encountered enough problems with the drive interface controller (or ones like it) and 3 Gbit/s SATA controllers to make a 3 Gbit/s jumper something worth implementing. 2) Worst case scenario, you should be able to enable the jumper and limit the drive to 1.5 Gbit/s and it should work. From [5], there should be no real disadvantage in raw speed since at the beginning of the drive, it's still about 15 MB/s away from saturing a 1.5 Gbit/s link (presuming you aren't doing something like using a port multiplier). Note that I don't know if the OPT1 jumper stops other things like NCQ (which I presume the drive has). Also I'd avoid reading too much into the TechARP review beyond a rough idea of the raw speed since they seem to have come to the conclusion the EARX new drive is slower then the older EARS drive based on what I think is a sample size one each. (I.E. All their actually saying is our single EARX is slower then one single EARS.) P.S. However remember no one can guarantee any specific model will work with your system, except perhaps your vendor. I know of someone who encountered a random compatibility problem with a WD? drive and some motherboard several years back. I never found out what the problem was but it sounded like something fairly well known to those who seel the motherboard but also something rather unusual. Nil Einne (talk) 21:53, 16 August 2012 (UTC)

From everything I've heard, SATA revisions are supposed to be fully backwards compatible. You'll just be limited to the features and speeds supported by the oldest hardware in the chain. Horselover Frost (talk · edits) 22:07, 16 August 2012 (UTC)

Plotting ping results on a graph

Resolved

I would like to plot some ping results on a graph. The data comes from the standard Windows ping tool and is in the format;

~ 16/08/2012 18:15:21.82
Reply from 173.194.78.94: bytes=32 time=53ms TTL=47

~ 16/08/2012 18:16:22.26
Reply from 173.194.78.94: bytes=32 time=19ms TTL=47

~ 16/08/2012 18:17:22.94
Reply from 173.194.78.94: bytes=32 time=30ms TTL=47

etc

The date and time have been added by me, and I can change it to any format if that would make plotting the results easier. The data I want to plot on the graph is the "time=(x)ms" part of each ping request against the date and time of the request. If possible I would like to do this in Microsoft Excel 97. The log file containing the ping results is over one thousand lines long, so I cannot do it manually. I have very little experience in plotting data on graphs, so I need lots of help and advice. Thank you for your time 92.233.64.26 (talk) 19:43, 16 August 2012 (UTC)

Well it will be easier if you have everything on one line, date time and response time, then you can load the data to excel and allow space separation to get it into fields. There are other products around lie Multi Router Traffic Grapher that can do this on a much bigger scale automatically. This awk command will do the conversion to combine on one line and strip back the time:

 awk '/^~/{a=$0};/Reply/{sub(".*time=","");sub("ms.*$","");print a,$0}'

Graeme Bartlett (talk) 22:02, 16 August 2012 (UTC)

Thanks for the reply. I am not familiar with "awk", is it a linux program? The windows version I downloaded from the gnu sourceforge page seemed to fail with the command above, perhaps because the command prompt was interpreting the special characters differently? 92.233.64.26 (talk) 00:14, 17 August 2012 (UTC)

In Windows, you should be able to use something like the script below. If you edit the lines above the first blank line, and save it with a .cmd extension, when you run it it gives you a CSV file which you can open in excel

set FAILURE=Failure
REM the above is what will be written to the third column if there is no reply	
set outfile=ping.csv
set host=www.bbc.co.uk
set attempts=10
set delaybetween=1000
rem the above is in milliseconds

echo wscript.sleep(%delaybetween%)>sleep.vbs
echo Attempt,Date,Time,Replytime > %outfile%
set count=1

:loop
ping -n 1 %host% | find /i  "reply from" > %outfile%.tmp
if errorlevel 1 goto FAILURE
for /f "tokens=7 delims== " %%T in (%outfile%.tmp) do echo %COUNT%,%DATE%,%TIME%,%%T >> %outfile%

:BACKFROMFAIL
cscript /nologo sleep.vbs
set /a count=%count%+1
if %count% LEQ %attempts% goto loop 
goto theend

:FAILURE
echo %COUNT%,%DATE%,%TIME%,%FAILURE%
goto BACKFROMFAIL

:theend
if exist sleep.vbs del sleep.vbs
if exist %outfile%.tmp del %outfile%.tmp

Hope this helps, davidprior ^t/_c 07:43, 17 August 2012 (UTC)

Well the awk that I used was under windows but done in the cygwin environment. I actually did test it on your sample data. The awk commands were quite standard, so the characters should not have affected anything, and should work on every version. If you use nawk you may get a more helpful error message. Another alternative would be an excel formula that selects every third line, and uses functions to edit the strings retrieved. I am a bit vague about the exact functions for excel. Graeme Bartlett (talk) 09:18, 17 August 2012 (UTC)

Thanks for the help everyone! 92.233.64.26 (talk) 11:16, 17 August 2012 (UTC)

Windows task bar disappearing

For the last week or two, the task bar in my Windows 7 system has been disappearing a few times per day. It is NOT hidden. I have it locked. If I log off and log back on (or restart), it comes back, for a while.

I have Norton Security and I've run Microsoft Safety Scanner and MalwareBytes, and they didn't find any malware.

Is there a solution for this problem? Bubba73 ^{You talkin' to me?} 20:18, 16 August 2012 (UTC)

I think we'd need a lot more info. For obvious stuff, you made sure it's not on auto-hide (doesn't seem like that's it, but check). Are you running anything peculiar in the background? It's possible that explorer is crashing. Are there any other things that trigger this, or other strange behavior? You might see if this happens in safe mode. Also try looking at msconfig and see what it shows you for both non-ms services and startup items. You might see if something new's been introduced there. Shadowjams (talk) 04:32, 17 August 2012 (UTC)

Yes, I made sure it is not auto hide. It just seems to disappear by itself and sometimes it comes back by itself. For instance, when I got up about an hour ago, it was gone. It stayed off while I used it for about a half hour, then I went to eat. I came back a few minutes ago and now it is back, and it came back by itself (I didn't log off or reboot). Bubba73 ^{You talkin' to me?} 16:29, 18 August 2012 (UTC)

And it has just been sitting there for a while, and the task bar has disappeared again. Bubba73 ^{You talkin' to me?} 21:13, 18 August 2012 (UTC)

loop 128 PNG files at 15 fps onto a 10 minute youtube video

This is for a scientific experiment, and the best way to do it is to project a high contrast series of stripes to my fruit flies to an iPhoone sitting on top of a transparent experimental arena; I created a bunch of stripes in different positions in MATLAB-- the trouble is that while I can find flv editors that will loop a single sequence of images ONCE, I cannot find an application that will write a single sequence over and over again into a single video file until a certain amount of frames has been reached. I'm basically using my iPhone so I would like to play a looping series of stripes off of Youtube (which I will upload to). I cannot use any browser-based methods (e.g. animated GIF) as there will light leakage from other components (I need blue light coming from the iPhone only, or black, else it will ruin the selective dual color imaging setup, as I am observing fruit fly behavior through a red filter and need the stripes of the phone to be invisible). The nice thing about Youtube is that the "controls" disappear after a few seconds. 137.54.29.134 (talk) 21:45, 16 August 2012 (UTC)

VLC media player can play a video in a loop in full screen mode on a PC. ImageMagick or GraphicsMagick can make a video from a sequence of frames, and can likely make a frame of stripes for you too. They are command line driven so can be quite flexible once you know what you are doing. You can put your modern broswer into full screen mode in modern versions so you onl.y see page content, so you may want to explore that option. Graeme Bartlett (talk) 22:24, 16 August 2012 (UTC)

Yeah, it is hard to believe your best option relies on an iPhone and YouTube… is the point of the experiment the light and flies or using an iPhone?
If you were to use an ordinary monitor you could tape over any extra lights (you'd presumably have to do this for other things in the room anyways). FFmpeg doesn't seem to quite support looping a sequence on its own yet, which is unfortunate. 128 divided by 15 is hard to divide 10 minutes by as well… can we assume looping the sequence 70 or 71 times would suffice (or 100, a nice round number)? ¦ Reisio (talk) 23:29, 16 August 2012 (UTC)

An iPhone is ideal because it matches the size of our 3"x4" arena. It's very hard to mount a monitor right on top or below a level arena, which is what must occur in order to avoid the effects of geotaxis (gravity-driven congregation in the "upper" portion of a non-level arena). Any further and the contrast is diminished. Right now, I know how to make a video from a sequence of frames, but what I need is for the loop to occur in the file itself (the iPhone Youtube app doesn't have a loop function). Of course, if there's an iPhone app that can turn its dashboard off and repeat videos, that would be awesome. 137.54.29.134 (talk) 23:48, 16 August 2012 (UTC)

According to http://google.com/search?q=iphone%20app%20video%20repeat there are such apps, including one named "Loop Video". ¦ Reisio (talk) 00:05, 17 August 2012 (UTC)

There probably is. Otherwise, if you can upload the images somewhere I can assemble the video as originally requested (except looped 70, 71, 100, etc. times and not 10 minutes exactly). The shell scripting I would use is so ugly I will not share it publicly. :p ¦ Reisio (talk) 23:56, 16 August 2012 (UTC)

The files are here here. 137.54.1.117 (talk) 20:38, 17 August 2012 (UTC)

To avoid network issues you should probably use the iPhone's own player to play a local video, though. Does that have controls that show up by default? If so how long do they take to disappear? Which model iPhone? ¦ Reisio (talk) 23:59, 16 August 2012 (UTC)

I found an app [6] which will play animated gifs in full screen.  Card Zero  (talk) 08:10, 17 August 2012 (UTC)

The reviews say it doesn't work-- I'm hesitant to try because of the price tag.

August 17

is the human brain a Turing Machine?

I was having a debate with someone and he asked me to prove that a human being was a Turing Machine. In some ways it seems so obviously true, that humans are at a minmum Turing Machines that I had never really thought through a proof or convincing argument. I can think of several but when I searched I was a bit surprised that I didn't find any definitive statements from Turing, Church, or others with a lot more credibility than I have on the subject. I just want to make sure I haven't missed something, has anyone like Turing, Church, Von Neuman, Chomsky, Dennet, etc. written on the topic? Mdebellis (talk) 02:26, 17 August 2012 (UTC) — Preceding unsigned comment added by Mdebellis (talk • contribs) 02:24, 17 August 2012 (UTC)

Is it literally a Turing machine? Clearly not (no such device can exist - infinite tapes are in rather short supply, for a start). Is it even metaphorically one? I very much doubt it. AndyTheGrump (talk) 02:29, 17 August 2012 (UTC)

I should have been more clear in my question, didn't want to make it too long, I recognize that it obviously isn't literally a Turing machine since there is no infinite tape but by that standard no computer is a Turing machine either, no computer has infinite memory. And the same goes for errors, no human can be without errors if they try to "be" a Turing machine but computers eventually can also make errors (not talking about software but about the HW actually failing) True, a computer will go a lot longer than a human before an error but the principle is the same, it seems tome that any implementation of a Turing machine is an approximation of the formalism. Mdebellis (talk) 16:50, 17 August 2012 (UTC)

Anything a Turing Machine can do, a person can do in principle. Bubba73 ^{You talkin' to me?} 03:26, 17 August 2012 (UTC)

Dennett has written a little on computers in Consciousness Explained, but I don't remember in what context :( Уга-уга12 (talk) 03:31, 17 August 2012 (UTC)

• A Turing machine, if the term means anything at all, has a discrete set of states and a well-defined transition matrix that determines how it behaves. The human brain has neither a discrete set of states nor a simple transition matrix. The Church-Turing thesis implies that anything algorithmic that the brain can do, can be replicated by a Turing machine, but there is lots of microstructure in the brain that isn't doing anything functional. To put this in different words, the human brain can perhaps be simulated by a Turing machine to any specified degree of accuracy, but not to perfect accuracy. Looie496 (talk) 05:57, 17 August 2012 (UTC)

I think the better question is whether the human brain is Turing complete. It doesn't matter if it is actually a Turing machine, and talking about metaphorical Turing machines is far less interesting than talking about whether it is Turing complete or not. --Mr.98 (talk) 13:09, 17 August 2012 (UTC)

I tend to agree with Looie that it's unclear how to apply these computing concepts to the brain. In any case, Turing machines can accept arbitrarily large inputs, so unless human memory capacity is infinite, the answer is presumably no. -- BenRG (talk) 18:18, 17 August 2012 (UTC)

There are two distinct questions: "is the brain a Turing machine," and "can the brain be reasonably-well modeled as a Turing machine?" The Chinese Room thought-experiment contemplates whether these questions are identical. Nimur (talk) 18:43, 17 August 2012 (UTC)

I think the question is intended as the opposite of whether the brain is Turing-complete (it obviously isn't, per the lack of infinite memory). Rather, it's whether a Turing machine could in principle simulate a brain, and yes, philosophers and some mathematicians have spilled a great deal of ink on this question. It's a sub-question of the Church-Turing thesis. These days I'd say most scientists agree that a TM could simulate a brain. See The Emperor's New Mind for one of the few contemporary exceptions. However, like theology, it's not something that can be scientifically or mathematically proven. 67.122.211.84 (talk) 18:48, 17 August 2012 (UTC)

Thanks very much to everyone who answered, they were all very helpful. I will check out The Emperor's New Mind. Although I'm not sure I agree the question is like theology. We can't scientifically or mathematically prove it one way or another now but I don't see any theoretical reason why we never will be able to. Actually, I think Ray Kurzweil assumes it to be a given that we will one day be able to simulate brains on computers in at least one of his books. He might be another author worth checking into. Mdebellis (talk) 20:51, 17 August 2012 (UTC)

I agree that there's no reason, a priori, to assume that this is unprovable. We can prove that many types of computational devices are Turing complete. When we know more about how mental computation works — we are still impressively ignorant on that front — we should be able to determine whether it is Turing complete or not. That we cannot do so now is just a reflection of our ignorance; there is nothing metaphysical or supernatural about it. --Mr.98 (talk) 01:32, 19 August 2012 (UTC)

Concurrency

Hello, I was wondering, can one actually implement reliable multithreading in software (w/o hardware support, like atomic fetch-increment-write back instructions or similar)? How does x86 do this stuff (I think there was some operation that was atomic, perhaps XCHG?)Уга-уга12 (talk) 03:23, 17 August 2012 (UTC)

Amateur programmer answering here - but I think I know the answer. Given that a Java virtual machine for instance can multithread, I think one can take this as a given - but as you say, you need at least one atomic instruction to ensure reliability. Java has for example the wonderfully-named atomic Boolean [7], and presumably this ultimately has to be supported at the hardware level. With regard to the x86 itself, see x86 assembly language#Instruction types: "Contains special support for atomic instructions (xchg, cmpxchg/cmpxchg8b, xadd, and integer instructions which combine with the lock prefix)". AndyTheGrump (talk) 03:51, 17 August 2012 (UTC)

One builds safe concurrent programs from operations like mutexes (I'm pretty sure that if one has one of mutexes, counting semaphores, and safe queues one can build the others just from that). So your question amounts to "how does one build mutexes". As the mutex article notes, this is typically done with an atomic instruction like test-and-set and compare-and-swap. These do require more of the hardware than do ordinary compare or arithmetic operations - they effectively interlock concurrent execution units while they run. So that, to my mind, counts as "hardware support". As Mutual exclusion#Software solutions says, one can build mutual exclusion without such an instruction. These work in single-processor multithreading environments, but they make assumptions about instruction completion ordering that do not necessarily hold in multi-processor environments. Multiprocessor designs can implement means of supporting these, like memory barriers - but those too require inter-processor hardware support. -- Finlay McWalterჷTalk 13:13, 17 August 2012 (UTC)

If you're working on a simple, single microprocessor/microcontroller (not a multiprocessor system, etc), you can simulate atomic test/exchange instructions by disabling all interrupts, doing the read and write, and then enabling interrupts again. Since a processor can only change thread if there's an interrupt to break the instruction sequence, this is reliable as long as you can disable all interrupts. This mainly applies if you're not using an operating system; if there is an OS you would use its mutexes, semaphores, etc. --Colapeninsula (talk) 15:32, 17 August 2012 (UTC)

Thank you everyoneУга-уга12 (talk) 17:26, 17 August 2012 (UTC)

.gif files do not animate on my browser

I suddenly found that my computer, while searching the internet for .GIF files, does not recognise pictures as animated GIF pictures, and ends up not animating them as they should. How to fix that problem? 72.235.221.120 (talk) 04:37, 17 August 2012 (UTC)

Are you sure those are animated GIFs ? There are also static GIFs. StuRat (talk) 04:39, 17 August 2012 (UTC)

Which browser and browser version do you have? Some have settings on whether to animate and whether to loop the animation (e.g. for Firefox, search the web for "image.animation_mode"). 94.101.10.162 (talk) 05:14, 17 August 2012 (UTC)

In Internet Explorer, if you press ALT + T and go to Internet Options → Advanced and scroll down to Multimedia, ensure that Play animations in web pages is not unchecked.—Best Dog Ever (talk) 05:56, 17 August 2012 (UTC)

Yes, they are supposed to be animated GIFs. I have Internet Explorer on Windows 7, and "Play animations in web pages" is checked. Oh and I forgot to mention, this gadget:

Digital World Clock The "name scrollng" option does not work anymore, presumely in conjunction with the failure to display animations. 72.235.221.120 (talk) 07:24, 17 August 2012 (UTC)

That link links to a jpg and does not animate. - Purplewowies (talk) 07:38, 17 August 2012 (UTC)

That is supposed to be an example picture. It is the gadget that fails to animate on my computer, along with all GIF files. The picture I posted here is not supposed to animate. 72.235.221.120 (talk) 11:12, 19 August 2012 (UTC)

Ubuntu 12.04 1) Delete Icons from taskbar and 2) Minimize all open windows

I have upgraded to Ubuntu 12.04, a late upgrade and that has given me a bunch of headaches.

• In 11.10 I used to delete taskbar icons using Alt right click Del, but it is not working in 12.04. See the unanswered question in Ubuntu forum.
• In 12.04 Window+D is not working to minimize all open windows!
  With my good wishes
  Tito Dutta ✉
  07:52, 17 August 2012 (UTC)

I assume you're using unity (and not Gnome 3). To see a summary of keyboard shortcuts, hold down the super (windows) key for a second, and it pops up a little reminder pane. For your latter question, the key combination is Window+ctrl+D, and the same again to restore them. -- Finlay McWalterჷTalk 12:10, 17 August 2012 (UTC)

For your first question, it sounds like you want to remove an icon (for a non-running application) from the Unity Launcher (the bar at the left). First alt+F1 to put keyboard focus into the launcher; then ↑ and ↓ to move to the icon you want to remove, then → to bring up its quicklist. Then arrow to "unlock from launcher" and ↵ Enter. -- Finlay McWalterჷTalk 12:27, 17 August 2012 (UTC)

Incidentally I've assumed you prefer keystrokes for this latter task; with the mouse, one right-clicks on the launcher icon, and again picks on "unlock from launcher". -- Finlay McWalterჷTalk 12:31, 17 August 2012 (UTC)

Window+ctrl+D is working  Great!

Post number 6 here has a screenshot. I want to remove those launchers. Their suggestion is not working in 12.04. I asked there few days ago but have not got any reply still. --Tito Dutta ✉ 14:25, 17 August 2012 (UTC)

is the linux is an flatform independent or not?

is the linux is an flatform independent or not? — Preceding unsigned comment added by Ravichandran123 (talk • contribs) 12:02, 17 August 2012 (UTC)

Independent from what? In what sense? ¦ Reisio (talk) 13:52, 17 August 2012 (UTC)

It's just me who cannot make sense of this question? Comploose (talk) 17:50, 17 August 2012 (UTC)

Strictly speaking, Linux was originally just the Linux kernel, a kernel that Linus Torvalds originally wrote, intended for the GNU operating system. GNU is intended as a Unix-like operating system that is comprised wholly of free software. Theoretically, for a kernel to be platform independent (I assume this is what you meant?) means it need only achieve hardware independence, since you can build an arbitrary software framework atop any given kernel. Bearing that in mind, I believe you will find your answer in List of Linux supported architectures, if I have correctly inferred what you meant to ask. BigNate37_(T) 18:48, 17 August 2012 (UTC)

who is the best seo company chairman in india?

usully best company chairmain having some principles it will heps us to doveloping our company ,is it useful for us or not? — Preceding unsigned comment added by Ravichandran123 (talk • contribs) 12:10, 17 August 2012 (UTC)

Companies associated with SEO (beyond simply properly assembling a website) are unprincipled. ¦ Reisio (talk) 13:53, 17 August 2012 (UTC)

New folders in Windows

On this Windows 7 computer, when I make a new folder now, the data it shows in the columns defaults to the ones for music files. There must be a setting somewhere to have it default to the standard ones for a new file. Is there such a setting and where is it? Bubba73 ^{You talkin' to me?} 13:09, 17 August 2012 (UTC)

There is, but in my experience no amount of configuring will make it stay that way. It's been like this since Vista. I heard it was because they changed most of the Explorer view settings backend but never updated the registry part that should control it. I imagine if consistency is what you want, your best bet is to replace Explorer entirely with something else. ¦ Reisio (talk) 13:58, 17 August 2012 (UTC)

I've never had this problem with new folders in Windows until about a week ago. Bubba73 ^{You talkin' to me?} 15:12, 17 August 2012 (UTC)

Well I s'pose technically you may have updated your Windows system about a week ago and something changed, but more likely about a week ago was the first time you started playing with new folders in whatever area of the filesystem you are playing in, and that area is one preconfigured to try and be smarter than you. Such areas include the desktop, and almost any top level directory in your profile directory, including anything starting with 'My '. ¦ Reisio (talk) 23:13, 17 August 2012 (UTC)

No, I've made hundreds and hundreds of new folders, and probably none of them were in "My...", in the profile, etc. Bubba73 ^{You talkin' to me?} 23:44, 17 August 2012 (UTC)

That's what I'm saying. Elsewhere Windows doesn't try to be so clever. ¦ Reisio (talk) 00:17, 18 August 2012 (UTC)

Market research, solar power, battery to USB

I'm trying to find a product in the market, or maybe it doesn't exist. I'm looking for an arrangement where a charging station with some sort of battery is recharged by solar panels, and then my gadgets can charge off that battery via USB. I have a solar panel that charges directly via one USB, but then my (only one at a time) gadget has to be in the same place where the sun is shining, when the sun is shining. I would want to charge the battery via direct sun during the day, and then recharge my gadgets off the battery via multiple USB charging ports at night (or on un-sunny days). Thanks if anyone can point me to such as device... — Preceding unsigned comment added by 94.208.75.76 (talk) 13:55, 17 August 2012 (UTC)

It might exist, but I should point out that it won't work very well. First, solar panels are highly inefficient, then you get additional inefficiencies when charging its batteries, losses while its batteries sit, and more inefficiency when its battery is discharged/the battery in your device is charged. So, by the time you get to the charge in your device, you might only have something like 1% of the energy that hit the solar panel. Then consider that rechargeable batteries get weaker as they age, and solar panels become less efficient, making the equation even worse. The result is that you'd need a huge solar panel and/or a very low power device to make this work.

Also, if you're going to schlep a battery along with you, you might as well charge it at home, so why add the additional complexity of the solar panel ? (The only scenario I can see is while camping or otherwise away from electrical outlets for an extended period, in which case hauling a large solar panel around won't be pleasant.) StuRat (talk) 15:30, 17 August 2012 (UTC)

You can get various solar powered devices (just Google "solar powered" or put "solar powered" in the Wikipedia search box), which would be a more efficient way of charging them, but apart from very low power devices like a wrist-watch (I've had a very good solar-powered Casio for several years) this is mostly just a marketing gimmick with disappointing results.--Shantavira|^{feed me} 09:24, 18 August 2012 (UTC)

Adobe_Flash#Alternatives is rather incomplete. What alternatives are there?

I don't mean alternatives whether to the Adobe Flash tool for creating Flash, nor to the Adobe Flash player for visualizing them. What others alternatives are there to Adobe Flash besides the ones linked there (html5, JavaFX and Silverline)? Wouldn't jQuery be a kinda alternative? jQuery could be even better, since it doesn't require installing anything, just turning js on.Comploose (talk) 17:32, 17 August 2012 (UTC)

jQuery isn't a platform, but sort of an 'API' for building web applications. So jQuery would fall under HTML(5). Unilynx (talk) 18:02, 17 August 2012 (UTC)

There's Gnash, Lightspark, and combining various HTML/CSS/JS things. ¦ Reisio (talk) 22:54, 17 August 2012 (UTC)

Reisio is wrong. Gnash and Lightspark are clearly alternatives to the Flash player, Not to Adobe Flash platform. The OP didn't ask about that. BTW, the Adobe Flash article is not incomplete. There are just these alternatives, which do not completely cover the functionality of Flash. OsmanRF34 (talk) 21:22, 18 August 2012 (UTC)

The thing that makes this very hard to answer is that Flash does many things. Depending on what you are trying to replicate, different software does the trick. If the functionality you care about is scripting, there are lots of alternatives. If it's playing movies, lots of others. If it's doing complicated vector graphics, there are others for that. The three linked to there do more or less all of those things; the other ones you've mentioned do some of those things but not all of them. jQuery can't play a movie, for example, in the way that Flash can, nor can it do as many complicated vector operations. You could use it in conjunction with other technologies, though, to replicate many of the functions provided by Flash. --Mr.98 (talk) 01:29, 19 August 2012 (UTC)

Scared straight for kids on the Internet

I'm worried about my young nephews, Huey, Dewy and Louie. Is there a Scared straight for kids that warns them off what not to do on the Internet?

Personally I don't have time to hang out on all the social media sites and find out the pitfalls of each. I work with databases. You've heard of weaving straw into gold? Well I'm brought in after the horses have already processed the straw and I'm expected to take their output and turn that into gold. Hcobb (talk) 17:41, 17 August 2012 (UTC)

Are you Donald Duck, by any chance ? There was a PSA on TV in the US which featured a girl who "sexted" her b/f, only to find the pic posted on the school (physical) bulletin board, and magically reappear every time she tried to remove it, with the perverted janitor taking a copy. Other than earning the ire of school janitors, that ad seems to get the point across about how anything you send electronically is accessible by everyone, forever. StuRat (talk) 17:50, 17 August 2012 (UTC)

Add to the top of that that face recognition is getting better and better. So, your pictures of you drunk or doing drugs as you were younger will be found some day. Comploose (talk) 21:45, 18 August 2012 (UTC)

Norton Security Suite

My internet provider offers Norton Security Suite as part of the subscription. Is it a good choice to provide antivirus, firewall, antispyware, etc? The PC previously had Windows Defender, which I hear is more of an antispyware than an antivirus. Should Defender not be used if Norton is installed? Thanks. Edison (talk) 19:10, 17 August 2012 (UTC)

It seems to work for me. I have seen reviews of Norton indicating that Norton has improved greatly in recent years. I would not run two different anti-malware products that are designed to do the same thing; they might conflict with each other. Jc3s5h (talk) 19:34, 17 August 2012 (UTC)

It's okay if you aren't paying (extra, in this case) for it, but keep in mind that if you ever change providers you might not be able to any longer use this application for "free", and might be motivated to replace it, which means retraining yourself (if ever so slightly). Good free antivirus apps are Avira and Avast! ¦ Reisio (talk) 22:58, 17 August 2012 (UTC)

I use Norton because I get it free from my ISP. It works for me but some people complain about it a lot. It is much better than Windows Defender, and don't use both at the same time. From time to time I also run Windows Safety Scanner and MalwareBytes. Bubba73 ^{You talkin' to me?} 23:41, 17 August 2012 (UTC)

It's not my favorite even among commercial antivirus applications, but to be fair what really makes Norton a pain is if you decide you want to replace it with something else (that is, if you decide to not pay to use it for eternity), as attempting to uninstall it (that's right, attempting) can often not only not uninstall it, but break your networking! If you like Norton and are happy paying for it (or for whatever bundles it in for free) for the foreseeable future, that seems sane enough. ¦ Reisio (talk) 00:35, 18 August 2012 (UTC)

The old PC seems to be damaged and not worth repairing. Is it still common to use a desktop, or do most users go for a laptop? I note that a big monitor and a conventional keyboard can be connected to a laptop to emulate a desktop. Are desktops more powerful, for a given purchase price? Edison (talk) 02:25, 18 August 2012 (UTC)

Until fairly recently, in the UK at least, you got more computing power for your money with a desktop, but laptop prices have continued to fall so that there is now little difference in price for the same power. You will still pay more in total if you need to buy a separate large monitor. Dbfirs 06:58, 18 August 2012 (UTC)

My experience (in the US) is that the only thing laptops have going for them is portability. Decktops have better CPUs, more memory, bigger and faster hard drives, and more USB ports. They are more expandable and adding more memory or HD is possible and cheaper on a desktop. In addition, you have a real keyboard, a real mouse, and a real monitor without having to buy additional ones. Bubba73 ^{You talkin' to me?} 16:25, 18 August 2012 (UTC)

Have to agree with Bubba73 here except to say laptops may also have an energy efficiency advantage (you can get energy efficient desktop CPUs and systems but they're rare whereas most products intended for laptops are energy efficient) and perhaps to note that I expect you're more likely to find a laptop with an SSD. Of course most systems nowadays are fairly energy efficient compared to 5 or so years ago. There are also a few other minor possible advantages, e.g. possibly non USB SD card readers (although that can be a disadvantage in compatibility other areas). Nil Einne (talk) 07:12, 19 August 2012 (UTC)

Inadvertent reinstallation of Windows XP

My usual PC suddenly quit opening Windows XP a month or so ago. so I've been using a borrowed laptop. The PC said to insert the installation disc. With that in place, it would open ok and I could access files and programs. But then somehow it went ahead and re-installed Windows XP. Now there is no sign of my old files or programs, except what came with the new Windows XP installation. Should it be possible to regain access to the old files and programs? Edison (talk) 19:47, 17 August 2012 (UTC).

Usually the first step in the install process is to format the disk partition. If it did so, and your files were there, then they are gone. It might technically be possible to restore those portions which weren't overwritten by the new O/S, but it's not likely to be feasible, unless those were some rather valuable files. StuRat (talk) 19:56, 17 August 2012 (UTC)

If the files are valuable and you are going to try to recover them, then don't use your new windows installation, but connect your hard drive to another computer for recovery. A high-level format doesn't actually delete the data, but it might be difficult to piece it together from fragments, and any files overwritten by the new installation will not be recoverable by any method. After something similar happened to me in the early days of Windows, I always save my data on a separate partition (sorry, I know that's not helpful to you just now), though Microsoft often makes this difficult because all defaults are set to save in subfolders of Windows. I suppose it's too late to mention regular backups, and unless you saved a disk image (or at least the old registry), the old software will have to be reinstalled. Sorry we can't give you much hope of recovery. There is software available that will recover pictures (e.g. Convar's PC Inspector Smart Recovery), and List of data recovery software might have something similar for other files. Dbfirs 21:03, 17 August 2012 (UTC)

If you had partitions set up and the installation process wiped them out, you may wish to look at TestDisk, which is an excellent open source tool for partition and file table recovery. BigNate37_(T) 21:10, 17 August 2012 (UTC)

Just to clarify some of what was already said: the format during Windows' installation does not overwrite data, but the actual writing of the OS files does. So you've probably lost data equal to the size of the Windows OS files, more likely at the beginning of the disk (which is more likely the previous OS files, and other older files of the previous system). ¦ Reisio (talk) 23:06, 17 August 2012 (UTC)

The format may not delete them, but it makes them inaccessible, even if they weren't yet overwritten. This is unless you're willing to resort to forensic methods to try to save portions of them. StuRat (talk) 23:35, 17 August 2012 (UTC)

It'd be a pain, yeah. ¦ Reisio (talk) 00:02, 18 August 2012 (UTC)

OSX 10.4/5/6 - Override "interactive" login and switch to textbox, username/password domain-enabled login

Our school has a domain login system set up so that users can login to their school account from most of the computers in the building. However, some of the class machines (ones that aren't considered "public") are set to an interactive, user-tile login screen that only allows login to local accounts. The only way to switch them to a domain login screen is to log in as an administrator and change the login options from inside the System Preferences, which is semi-permanent until someone goes back and changes it. Is there a shortcut or other method to perform a one-time override and force the system to show the domain login screen? (Kind of like double-tapping Ctrl+Alt+Delete in most versions of Windows XP) Hmmwhatsthisdo (talk) 22:11, 17 August 2012 (UTC)

stripping a video of red and green, keeping blue channel only

I start with a blue and black only video and converted it to mpeg to upload to Youtube so I can put my iPhone next to a 3"x4" arena of Drosophila and image them with red light. However light from the red channel seem to be leaking through because they are visible on my camera which has been optically filtered to accept red light only. It is absolutely required that there be zilch/nada/zero output coming from the red channel otherwise it will disrupt the imaging of the flies in red light. The blue light is to drive fly behavior only. 137.54.1.117 (talk) 22:51, 17 August 2012 (UTC)

Maybe I should ask, how would I completely remove the red and green channels from my video? 137.54.1.117 (talk) 23:12, 17 August 2012 (UTC)

I'd say making it lossless would be a good start, and MPEG formats just aren't usually meant for that. Maybe a lossless JPEG2000 sourced MJPEG would be a better idea. ¦ Reisio (talk) 23:27, 17 August 2012 (UTC)

Most video data is not stored as RGB pixels (as you have become accustomed with still image formats). So, it's nontrivial to extract a "red only" "channel." It can be done, but you should be aware of the caveats.

Even JPEG uses a subsampled yuv colorspace, (not RGB values for each pixel); so JPEG isn't a great choice if you're planning to filter specific colors. Motion JPEG has an advantage over MPEG because it uses no interframe coding, but each individual frame is still compressed with a pixel-position-altering, color-altering lossy JPEG algorithm. For scientific image processing, you should use uncompressed, unconverted video if possible; or tread very carefully with the image-data.

You might try putting a blue-only filter on the display screen when you are filming/capturing the test scene, and a red-only filter on the camera - to help isolate the signals you care about before you even capture the video. Nimur (talk) 00:26, 18 August 2012 (UTC)

RE: lossy JPEG: hence JPEG 2000 (or other lossless JPEG), but I couldn't comment on whether you can actually easily create an MJPEG…2000. :p ¦ Reisio (talk) 00:41, 18 August 2012 (UTC)

JPEG2000 can use a lossless scheme only after color-space conversion, which might contain roundoff errors! Another caveat to the uninitiated video-processing engineer!Nimur (talk) 01:08, 18 August 2012 (UTC)

Heheh, woe! If it were me I'd use a light that only emitted the wavelength I wanted and obscure as required. :p ¦ Reisio (talk) 02:18, 18 August 2012 (UTC)

An optical filter isn't going to be 100%. Sounds like you need to digitally filter it instead (which is pretty much what you are asking about, I'm just pointing out the futility of the optical filter). StuRat (talk) 23:31, 17 August 2012 (UTC)

I think optical filters—a blue one on the screen and a red one on the camera—are the only hope here. Unless you're using super-expensive calibrated equipment, you can't expect to show blue on a screen and record it on a camera without leakage into the R and G channels. LCD subpixels emit a pretty broad spectrum, and there's no range of the visible spectrum that's detected by only one of the camera's three sensor types (otherwise it couldn't distinguish hues in that range). Cameras do a lot of internal processing of the raw sensor data even before JPEG compression. -- BenRG (talk) 02:09, 18 August 2012 (UTC)

I could certainly write a program to read a pic, strip it of all colors but the desired one, save it again, and create an animated GIF from those frames. That would just need a pre-processor to split the video into single frame images, and a post-processor to convert the animated GIF to your desired format. How many frames, at what res, are we talking about, though ? (Too many would make it take too long to process.) StuRat (talk) 02:31, 18 August 2012 (UTC)

August 18

Cantenna

Does it matter what type of can you are using for it? I used a Quaker oats can, which seems to be from a different, lighter material than say baked beans. Comploose (talk) 17:49, 18 August 2012 (UTC)

From our article "...antennas made with an empty metal can." I have never seen a metal Quaker oats can; aren't they just plain cardboard? Pringles cans are a common choice, which are mostly cardboard, but they have a metallic lining that apparently works well. SemanticMantis (talk) 17:59, 18 August 2012 (UTC)

No, Quaker oats cans are not plain cardboard, they seem to have a kind of aluminum foil lining. Is, for example, a cardboard cylinder covered by aluminum foil useless for a cantenna? Comploose (talk) 18:07, 18 August 2012 (UTC)

Network components

What is difference between a a- router b- wireless USB adapter c- access point 123.201.86.235 (talk) 20:03, 18 August 2012 (UTC)

Look at:

a- router b- Wireless network interface controller c- access point OsmanRF34 (talk) 21:12, 18 August 2012 (UTC)

Django + jQuery

If you have a Django back-end and a jQuery front-end, how do both systems communicate with each other? I've heard of XML and JSON but how does it happens? Does one system save information in a JSON or XML file and the other reads it? And where are these files located? Comploose (talk) 21:43, 18 August 2012 (UTC)

1.   Any number of ways

2-3. Something writes to a file (in XML or JSON if you like), and then something else reads it (or the reverse, or both, or any combination)

4.   While some preassembled solutions may dictate a location, there are basically no special requirements as to location

¦ Reisio (talk) 22:33, 18 August 2012 (UTC)

Basic concept: Django is server-side (Python) — it is run by the server computer. jQuery is client-side (Javascript) — it's run by the user's browser. The standard AJAXy operation goes like this: 1. the user loads the page; 2. after the page loads, a client-side script launches which queries the server-side code; 3. the server-side code takes the query, and spits an answer back in a given format (e.g. XML or JSON) that the client-side script can understand; 4. the client-side script takes the info it has received, and does something with it (e.g. display it on the screen).

Information is generally not written to a file in the way you seem to be indicating — only server-side scripting can edit or read files. So when you do have something that needs to be saved as a file (or written to a database), the client-side scripting needs to send it to the server-side scripting, and the server-side scripting then does something with it.

Let's consider a very simple example. I want my users to be able to search a very large database in real-time without the page refreshing. I set up a server-side script that takes in search parameters and spits out results. I then make a form that, upon the user typing in a search query, has a little bit of Javascript that sends a query to the server. It waits for a response. When the server returns results, the Javascript formats it into HTML and dynamically inserts the content into the page. That's basically how Gmail and any other page that updates "instantly (without reloading) works. JSON and XML are just different ways the server and/or client scripts can format the data they are exchanging.

As for Django and jQuery, it really depends on the application. I don't use Django, but you really will want to know specifically what you're trying to exchange, data-wise, to set up code that would do it. (jQuery is just a nice front-end for Javascript, it does nothing special in this respects except it makes sending AJAX queries and parsing JSON very easy.) --Mr.98 (talk) 01:22, 19 August 2012 (UTC)

fights on a sim

Where could i get a computer fight simulator that takes in varibles and uses math to solve the fight and fights between comic characters. — Preceding unsigned comment added by 205.142.178.36 (talk) 22:18, 18 August 2012 (UTC)

where am I getting the glyphs?

The appearance of one word in Gothic alphabet on another RD made me wonder: How can I know what font my computer (or browser) chooses for a given obscure segment of Unicode? —Tamfang (talk) 00:01, 19 August 2012 (UTC)

Illegal copies online

How difficult is it to remove illegal copies of your books/games/software online? Why is it so easy to find something, not only through emule and torrent, which are decentralized, but also for direct download? The copyright owners shouldn't have any problem finding those either. Comploose (talk) 00:06, 19 August 2012 (UTC)

There are many issues. One is that there are a lot of sources — it's a game of whack a mole. Another is that it takes time to send out take-down notices, and if they are ignored, you have to file lawsuits — which costs money and time. Another is that there are hundreds of different jurisdictions — getting a copyright violation dealt with in the USA is different than the UK which is different than Sweden which is different than Germany and so on. There are different laws, different languages, and so on. --Mr.98 (talk) 01:27, 19 August 2012 (UTC)

Drawpad

What is the cheapest, the best, and the most accurate drawing pad for PC. — Preceding unsigned comment added by 76.16.47.115 (talk) 03:45, 19 August 2012 (UTC)

Do you mean a digitizing tablet ? StuRat (talk) 03:49, 19 August 2012 (UTC)