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January 8

Average amount of time for two-qubit entanglement.

I was wondering if anyone knows what the average amount of time is for an entanglement of two-qubits. I would have to assume that the amount of time is longer than say for seven qubits. This question is obviously about quantum information science. Thanks. Lighthead ^þ 01:52, 8 January 2012 (UTC)

Okay... I guess I'll never know. Thanks for the fast response. Ha ha ha! Lighthead ^þ 22:32, 11 January 2012 (UTC)

laser toner compostable?

Is waste laser toner suitable for a garden compost heap? If not, are there other ways of disposing of it appropriately? RogerSawkins (talk) 02:12, 8 January 2012 (UTC)

Laser toner is plastic. It is essentially bioinert, which means while it won't poison the compost heap, it won't actually compost, so that's a pointless thing to do with it. It's non-hazardous waste. 87.115.57.93 (talk) 02:54, 8 January 2012 (UTC)

The laser toner cartridges I handle come with some pretty clear warnings on handling and disposal, including not getting it on your skin, washing it off immediately, not inhaling the dust, etc. Now they're probably just covering their butts so to speak in case in fifty years' time some disease gets linked to it, but personally it's not something I'd be putting in my compost. If you type "laser toner recycling" into Google it should come up with a number of suggestions of suitable locations near you to send your cartridges and toner for recycling, assuming you don't just want to put it in a plastic bag and chuck it in the bin. --jjron (talk) 10:46, 8 January 2012 (UTC)

The toner may be inert, but that does not mean that it's harmless. Think asbestos. The physical shape of the particles can cause irritation and illness without chemical interaction. Or, macroscopically, think Claymore. If well-maintained, it's bio-inert, but certainly not harmless ;-). --Stephan Schulz (talk) 10:50, 8 January 2012 (UTC)

And that's not just theory. Laser printer toner certainly can irritate your skin in a purely mechanical way. [1].

APL (talk) 11:12, 8 January 2012 (UTC)

Our very own Toner has many mentions of the hazards and environmental issues. A simple Googling "Laser printer toner disposal" provides numerous links to companies that deal with the proper recycling and disposal of printer cartridges and peripherals. fredgandt 11:52, 8 January 2012 (UTC)

8GB of RAM, but OS only seeing 7?

Resolved

I bought a laptop with following specs:

Windows 7, 64-bit Sandy Bridge, i7 quad-core 8GB, 1333 Mhz RAM

But in Windows Task Manager, under the Performance tab, it says that total physical memory is only 7084 MB, instead of around 8000 MB. Where did that 1GB go? Acceptable (talk) 03:17, 8 January 2012 (UTC)

Part of it is probably used for video memory. Bubba73 ^{You talkin' to me?} 03:26, 8 January 2012 (UTC)

Read this. Von Restorff (talk) 04:17, 8 January 2012 (UTC)

Thank you very much! That was exactly what I was looking for :). Acceptable (talk) 17:53, 8 January 2012 (UTC)

You are very welcome of course! Von Restorff (talk) 22:20, 8 January 2012 (UTC)

MatLab help

Resolved

Hi there. Not really a _question_, but could someone with access to MatLab do

fir2(16,[0 1],[1 1]);

and post the results? Thanks. 195.89.37.162 (talk) 13:05, 8 January 2012 (UTC)

I'm not familiar with that command, but when I run it I get a 17 column vector, with all zero entries, except for a 1 in position 9. Also, you can compute most matlab commands in GNU Octave for free :) SemanticMantis (talk) 15:51, 8 January 2012 (UTC)

Thanks very much. I thought it might be some appalling nth-complexity infinite binary Chebyshev/K!sdra thing, and I didn't want to try and replicate fir2.m just to calculate 17 numbers. Tevildo (talk) 17:09, 8 January 2012 (UTC)

In case you need to use this algorithm again, googling turned up an implementation for Octave here, and one in Scipy here (Scipy is a set of packages for Python (programming language), and is also free and open-source). 130.88.73.65 (talk) 12:18, 9 January 2012 (UTC)

<div> tag margins and displaytitle

Resolved

I'm currently renovating my userpage and using a lot of <div> tags. However, I can't seem to get the right margin to behave. The nested div tags also don't respect the right margin of the parent div box either. The edges overflow past the width of the page, making the horizontal scroll bar appear. What am I doing wrong? I'd just like the right margin to display the same space as the left margin (adjustable to screen size of course). Fixed first problem on my own, heh

Also, is there a way to completely suppress the title of a page? i.e. I would like the "User:Obsidian Soul" to disappear as it is quite redundant. {{Displaytitle}} doesn't seem to be doing anything though.-- Obsidi♠n Soul 16:42, 8 January 2012 (UTC)

The documentation for the DISPLAYTITLE magic word points us to m:Manual:$wgAllowDisplayTitle, which says the magic word allows you to "override the title of a page, provided the selected title normalises to the same canonical title". Presumably you're trying to set DISPLAYTITLE to nothing (or nbsp or something), which obviously doesn't canonicalise to "User:Obsidian Soul". Without the other setting mentioned on that page (which, unsurprisingly, it looks like en.wikipedia doesn't enable) you can't use DISPLAYTITLE to blank a page title. -- Finlay McWalterჷTalk 18:20, 8 January 2012 (UTC)

Oh well... I was under the impression that you could do more with it in enwiki. Anywho, TYVM :) -- Obsidi♠n Soul 18:49, 8 January 2012 (UTC)

That is not true; you can use DISPLAYTITLE to blank a page title. Von Restorff (talk) 19:54, 8 January 2012 (UTC)

I removed the title on Obsidian Soul's userpage and and changed the title of his talkpage. I also changed the title of Finlay McWalter's userpage to Slay McWalter. Von Restorff (talk) 20:13, 8 January 2012 (UTC)

Google Account

Hi! Today my friend send me a link to Youtube. I clicked it but had to download Adobe Flash Player because I could not watch videos on Internet Explorer before. I automatically got the Google Account, but I don't want it. How can I delete it but keep my Gmail? Will it disappear if I delete Google Account? Thank you in advance. — Preceding unsigned comment added by Atacamadesert12 (talk • contribs) 18:23, 8 January 2012 (UTC)

If you delete your Google account you also delete your Gmail, sorry. Von Restorff (talk) 19:50, 8 January 2012 (UTC) p.s. Why do you use Internet Exploder? Firefox is free!

If you already had a gmail account, you already had a google account; they are one in the same and have been for some time. ¦ Reisio (talk) 21:34, 8 January 2012 (UTC)

January 9

Alternatives to texvc in MediaWiki

I asked a little while back but didn't get any answers, so I'll ask again: Are there any known alternatives to the standard Math package for MediaWiki distributions? My webhost apparently doesn't support PHP commands like passthru() and exec(), and I'm guessing those are needed in order to parse the Latex markup. So... are there any alternatives or workarounds so I can get some good-looking math working on my wiki? Thanks very much. 216.221.63.30 (talk) 01:51, 9 January 2012 (UTC)

I couldn't find one. Category:Math_extensions. Why don't you just change hosts; or ask your webhost about the PHP commands you need? Von Restorff (talk) 12:52, 9 January 2012 (UTC)

The web-host's limitation is not simply that "exec" is unsupported. (That would be a silly limitation, in and of itself!) The web host is denying its users the ability to execute arbitrary programs - which is a form of sandboxing, for security-reasons. Every web-based implementation of TeX that I know of requires native executables.

Your options are, unfortunately, to switch web-hosts (look for any host who offers "shell access," which is shorthand for "you're free to run whatever user-space programs you need." Or, you can migrate yourself off of TeX to some other technology for rendering math. Nimur (talk) 19:30, 9 January 2012 (UTC)

facebook

So, I created a facebook account a little while ago that I have done nothing with since then, but it seems it may now be useful, I am supposed to be working on my current university project with a bunch of people I have never met before, and one of them managed to find me on facebook and we exchanged a few messages. Only trouble is, now they want me to email them some stuff, but I don't know their email address. I have been led to believe it is possible to find such things on the site, hence why I was encouraged to get on there before, when something similar happened, but I cannot find where. So, how do I go about emailing some files to someone I know only from that site?

148.197.81.179 (talk) 11:41, 9 January 2012 (UTC)

You should be able to find their email address in the info tab on their profile page. If you can't find it, send them an e-mail on facebook itself and ask for their email. Mrlittleirish 11:48, 9 January 2012 (UTC)

(edit conflict)You can

• upload the files you want to send somewhere (if you do not have and want a dropbox you can use something like filehosting.org) and then send them a message via Facebook asking them for their email address and explaining how they can download the files
• enter their name in Google and look for their email address

Von Restorff (talk) 11:51, 9 January 2012 (UTC)

You can also attach files through the Facebook messaging service (click the little paperclip icon while writing a message)). Or you could, you know, just ask them for their e-mail address (sometimes the most obvious things are the best). --Mr.98 (talk) 12:49, 9 January 2012 (UTC)

Smartphones and apps that run everywhere

Are mobile apps normally able to run on every main smartphone (BlackBerrys, Androids, iPhones, Windows Mobile)? Do Java or HTML5 (or other run-everywhere technology) make this possible? 88.9.214.197 (talk) 17:17, 9 January 2012 (UTC)

Mobile apps are limited by their execution environment (the OS), so one app has to be rewritten by the developers if they want to target a different platform (Obj-C for iPhone, Java for Android, C# for Windows Mobile). As for HTML the one that takes care of interpreting and rendering the code is the browser, so in theory that allows to serve the same code (say, HTML + CSS + JS) to every user regardless of their operating systems, as long as they have a browser that supports it. In practice, though, there are many things that browsers interpret differently, so making a "universal" application requires a good deal of extra development to make sure that it behaves coherently. See [2] [3] for feature availability tables. HTML5 is among other things an attempt to standardize web practices in order to minimize cross-browser conflicts, but it still has some ways to go — Frankie (talk) 19:29, 9 January 2012 (UTC)

Frankie is correct, though I think he's too generous when discussing Java and HTML 5. Native apps are not browser-based "apps", so the real answer to the original question is "no". Side note — Unity is an example of some middleware that runs on both Android and iOS, and I've talked to one engineer who got his Unity game, authored under iOS, running over on an Android phone in 20 minutes. Completing the entire port took a lot longer, of course, but at least he got it running right away. Comet Tuttle (talk) 19:54, 9 January 2012 (UTC)

Connecting an Atari standard joystick to a modern PC?

Does anyone know if it's possible to connect an Atari standard joystick to a modern PC? I have got E-UAE and VICE running on my Fedora 14 system, but it's a bit awkward to use the numeric keypad as a joystick. On E-UAE, the host PC's mouse works as the Amiga's mouse, and the Commodore 64 doesn't even use a mouse as standard. But I would feel better using an actual joystick. I already have one, I just can't use it at the moment, as modern PCs lack an Atari standard connector. Is such a thing possible? JIP | Talk 19:20, 9 January 2012 (UTC)

ThinkGeek has sold USB versions of the standard Atari joysticks in the past. They appear to be out of stock right now. If your computer has a 9-pin serial port, you should be able to plug an old joystick in. Then, the issue isn't "can I plug it in?" The issue is "Will my program be smart enough to scan my serial port?" Struck previous - I never noticed that was a "game port" on my computer. -- kainaw™ 20:02, 9 January 2012 (UTC)

Atari 2600 joysticks didn't use the standard 9-pin serial port. Comet Tuttle (talk) 20:20, 9 January 2012 (UTC)

(ec)That won't work. An Atari joystick, while it uses a DB-9, isn't an RS-232(EIA-232) device. Instead it's a digital microswitched system which grounds various lines on the DB-9 when different directional switches are closed (the pinout is here). To make it work with an existing port, that port needs to have five lines of GPIO (well, GPI) for NSEW and one button, which a COM port won't do. A game port does (because it was always intended to connect analog and digital joysticks); the two aren't electrically compatible, so some circuitry between the two is necessary - this page has diagrams; I don't know if anyone sells these kind of things made already built (the forums for atari and c=64 emulators will know, as people there sometimes build and sell hardware to allow ancient peripherals to connect to modern PCs). It's another matter whether JIP's computer has a game port, and whether the emulators in question will support a digital joystick on a game port. -- Finlay McWalterჷTalk 20:20, 9 January 2012 (UTC)

Slight correction: it's a DE-9 not DB-9. -- Finlay McWalterჷTalk 20:43, 9 January 2012 (UTC)

Boosting WiFi with aluminum foil

The wireless router in my house is located in the room with our two wired desktop computers, and unfortunately isn't near the center of the house. I've found several websites and videos that claim that folding aluminum foil into a parabolic shape and placing it behind the antennae can help reflect the signal and make it stronger in the rest of the house. Does this really cause a significant improvement in signal strength? Since the router is next to the wall, our encrypted WiFi signal isn't doing the neighbors any good, so if there is an easy mechanism to reflect the unusable area of the signal back centrally, that would be great for how our electronics are laid out. Buying a better set of antennae seems like the sure-fire way to solve the problem (or, of course, moving the router and maybe buying WiFi cards for the desktops), but it's not that important and I was hoping for a simple do-it-yourself solution, which is why the tin foil suggestion intrigued me. For reference, the router is a wireless Linksys of the WRT54 series with the proprietary firmware. Thanks!--el Aprel (^facta-_facienda) 22:46, 9 January 2012 (UTC)

A parabolic reflector will boost the router signal in one direction only, and if you have multiple receivers, this isn't necessarily going to help. if they are all more or less in a line, and you point it in the right direction, it might improve the signal - you'd have to experiment. AndyTheGrump (talk) 22:58, 9 January 2012 (UTC)

I suspect that adding external reflectors to a WiFi antenna will cause multipath interference. This may actually reduce the signal integrity, even if it increases the signal intensity. 802.11 WiFi is a sophisticated protocol, and unless you have access to the internals of the radio system (the amplifiers, the firmware, and so forth), your attempts are probably going to be futile. Nimur (talk) 23:22, 9 January 2012 (UTC)

It’s fairly simple to run wire (coax or ethernet) through the various outlet boxes of a house, if you’d like to relocate such a device (do disable the power at the breaker/fuse box first to avoid electrocution, however :p). You could also route a network connection from a single wired desktop to another over a USB cable… though a simple network switch box and a couple short cables shouldn't run you much, and would be (marginally) simpler to set up (via the OS). ¦ Reisio (talk) 01:12, 10 January 2012 (UTC)

However make sure to check if running cables in your house is actually legal. In Australia where I live you have to be licensed to perform such work, even just for data cables. Vespine (talk) 03:19, 10 January 2012 (UTC)

I'd also note that running data cables alongside the mains system may in itself possibly cause problems with crosstalk. Getting a home WiFi system to work optimally seems to be something more closely related to alchemy than science, and can be extremely frustrating. From personal experience, I'd recommend trying to move the router to a central location (if possible) as the best starting point. You might also want to try a WiFi scanner like InSSIDer out to see what channels nearby routers are using - some routers seem to be rather stupid in channel selection, and seemingly prefer to keep each other company on the same channel, rather than finding one with less usage... AndyTheGrump (talk) 03:55, 10 January 2012 (UTC)

YouTube about Linksys wifi improvement. Software and hardware solutions. fredgandt 04:16, 10 January 2012 (UTC)

I've had good experiences with extending the range of a USB Wifi dongle a bit by using a Cantenna made from a simple Pringles tin. So you can always experiment to see if it improves the signal. S_peakF_ree ^(talk)_(contribs) 15:52, 12 January 2012 (UTC)

Issue with java and thread halting.....

I am trying to halt a thread in java. Since thredName.stop() is deprecated and considered dangerous, i looked to see how i should do this. All sources that i have found showing a safe way to stop a thread are saying you should have a boolean value that is toggled from outside of the thread, and the run method checks this value every now and then.

See: http://www.exampledepot.com/egs/java.lang/StopThread.html http://stackoverflow.com/questions/3194545/how-to-stop-a-java-thread-gracefully

Its all the same stuff....

public void run() { //do stuff if (done) return; //more stuff }

lots of variants, but they all have the same problem... the thing i want to do inside the run method is a blocking statement, so its impossible to terminate it if one of these statements runs forever. The only thing i can think of is to make the call non blocking, but this is done by threading and we are at the same problem i started with.

How the heck do i stop a thread that might be running a statement that is blocking???? Thanks for any input, and if it is needed that i show my specific example i will do so.

172.162.110.233 (talk) 23:55, 9 January 2012 (UTC)

The appropriate technique is explained in the Java Thread Primitive Deprecation guide, How do I stop a thread that waits for long periods (e.g., for input)?. The bottom line is, use Thread.interrupt() to send an InterruptedException (which your thread should handle in a catch block). This will interrupt your thread in a safe way. In some cases, you can also cause the thread to interrupt in an application-specific way, such as asynchronously closing a socket (which will cause any thread waiting on socket IO to terminate and/or throw an IOException). Nimur (talk) 00:46, 10 January 2012 (UTC)

Im not sure i get how the thread should check it, but i have tried thread.interrupt() to no avail.... here is my code:

http://pastebin.com/chAzCMCT

172.162.110.233 (talk) 01:26, 10 January 2012 (UTC)

If you'll trim that down to a runnable example I'd be happy to take a look. --Sean 20:32, 10 January 2012 (UTC)

This is a known issue with the ScriptEngine API; it provides no mechanism for interrupting computation. The link suggests using Mozilla Rhino directly, or just using the unfortunate stop() (which really can ruin your day if the thread had something locked at the time). --Tardis (talk) 08:27, 12 January 2012 (UTC)

January 10

iPad charging

I have a car charger for my iPhone, will it also charge my iPad please?--85.211.148.143 (talk) 07:27, 10 January 2012 (UTC)

Mine does. You may be able to find more specific info on the web site of the company that made the charger. Dismas|^(talk) 07:29, 10 January 2012 (UTC)

Some do, some don't (in particular, older ones might not provide enough power, so it would be like plugging the iPad into a little iPhone charger.) --jpgordon^{::==( o )} 18:06, 15 January 2012 (UTC)

Amateur architectural design programs

Let's say I wanted to design a new home, not in a super technical way, but in a detailed enough way that I could communicate these ideas to a builder, what is the software landscape right now for that kind of task? I know there are CAD programs that can do amazing things, but those aren't necessarily oriented for residential home construction. Similarly, I know there are some cheap programs that do the same thing that you can buy at your local office supply store. I'm looking for some idea of if there's a standard, what those might be, and any other relevant points. I'm aware of google sketchup, which I've toyed around with some, and while I like, Isn't as specialized or robust as what I'm thinking of. Shadowjams (talk) 09:38, 10 January 2012 (UTC)

Hi, we have a List of computer-aided design editors (I don't have any experience of any of them, but the list may be worth a read)Darigan (talk) 13:15, 10 January 2012 (UTC)

Second Life is a free 3D virtual world you can build in. fredgandt 13:24, 10 January 2012 (UTC)

P.s. YouTube (not new video) and guardian.co.uk report on architects in SL. There is a lively community and many groups. You could find people (some professional, some not) for advice and help very easily. Many universities and collages use SL, as do many real world architects (cite missing 'cause this isn't an article. I know SL very well). Since it is free and web based (client download required), you can also share your work with anyone who has access to a (reasonable) computer. fredgandt 13:40, 10 January 2012 (UTC)

Maybe worth mentioning that the standard approach is to discuss your ideas with an architect, who then draws up the plans that the builder works from. For something like a whole new house, the plans will probably need some sort of sign-off from a structural engineer. And in many countries there will be some planning approval process that checks your new house meets local building codes. The "super technical" plans are needed for all these purposes, and most builders don't have the experience or time to draw up these plans themselves. Gandalf61 (talk) 13:27, 10 January 2012 (UTC)

Some students at the school where I used to work, used Blender and this tutorial http://yorik.uncreated.net/tutorials/architecture-blender.html to create some amazing ideas for buildings. --TrogWoolley (talk) 15:52, 10 January 2012 (UTC)

Thanks for that link TrogWoolley, very good tutorial, I am going to try that! Von Restorff (talk) 19:42, 10 January 2012 (UTC)

I have used Google Sketchup for this purpose, which is very simple to learn and free of charge. Highly recommended! 88.90.108.120 (talk) 19:52, 10 January 2012 (UTC)

DOWN LOAD SOFT WARE OF BENZ ACTRESS COMPUTER SYSYTEM

I WANT TO DOWNLOAD SOFTWAR OF CPU OF COMMERCIAL BENZ ACTRESS . fOR THAT WAHT I HAVE TO DO?? — Preceding unsigned comment added by 46.153.243.16 (talk) 11:18, 10 January 2012 (UTC)

Mercedes Benz Biome Windows 7 Theme? fredgandt 12:50, 10 January 2012 (UTC)

I have to congratulate you for making sense of that question. I could get as far as understanding the OP wants to download some software, but the "commercial Benz actress" bit was lost on me. JIP | Talk 19:48, 10 January 2012 (UTC)

Purely a Google guess. fredgandt 06:18, 11 January 2012 (UTC)

Possibly Julie Benz is the actress. Maybe something seen in Dexter? Who knows? fredgandt 07:25, 11 January 2012 (UTC)

C# getting the amplitude of the sound read by the microphone

I would like to have access to the amplitude of the sound being received by the microphone, what would be the simplest way to do this?Bastard Soap (talk) 11:22, 10 January 2012 (UTC)

15 inch cheap thin ssd like zenbook?

hi, this is what I'm looking for: a cheap, (about 700 dollars) 15 inch laptop built like a zenbook, meaning it has an SSD, is thin, has no hard-drive dvd or cd drive, and 4 GB of RAM, an i5 processor. unfortunately I can't find a zenbook in 15 inches... whats the closest thing to my description? — Preceding unsigned comment added by 188.6.71.91 (talk) 13:50, 10 January 2012 (UTC)

Something like a Acer Aspire AS5750G-6653? It is 29 bucks over your budget, but it has 6 GB RAM. Von Restorff (talk) 20:35, 10 January 2012 (UTC)

Hi! It's promising, but is a typical laptop (not an "ultrabook") which makes it heavier. Above, I made a mistake, now corrected: by "no hard-drive" I meant "no cd/dvd drive". Basically, I would like what you linked but thinner, lighter due to SSD instead of hard-drive, and no CD or DVD drive. Maybe what I'm describing simply doesn't exist? --80.99.254.208 (talk) 10:59, 11 January 2012 (UTC)

Ultrabooks are going to be more expensive than larger laptops, because of the effort they have to put in using smaller and colder running components, and higher density batteries. I suspect you are right in assuming the machine you want doesn't exist, especially with an i5. Is there a reason you need such a fast processor in such a small form factor? Maybe an i3 powered laptop might suit your needs? 192.84.79.2 (talk) 15:06, 11 January 2012 (UTC)

ASP.NET session expiring

In Microsoft ASP.NET, is it somehow possible to have the ASP.NET web application automatically fire an event when the user's session expires, or do I either have to wait until the user makes an HTTP request and check if the session has expired, or devise some contraption where the web application starts a new thread that periodically checks whether users' sessions have expired? All this makes me wish HTTP was designed so that the user going to a different page, or closing his/her browser, would send some signal to the web server. But no, such a thing never happens. The web server only gets a signal when the user starts browsing, not when he/she stops browsing. JIP | Talk 19:53, 10 January 2012 (UTC)

Check this and the code under "Detecting when a session has timed out" and the text under "Session Timeout Event" on this page. There is an event that is fired when the session expires, so I imagine you could write an event handler for that.--Best Dog Ever (talk) 20:14, 10 January 2012 (UTC)

You can design your server-side application to communicate with a client-side script, e.g., JavaScript. For example, AJAX refers to the ensemble use of client-side JavaScript and lightweight communication between browser and server, to provide a more sophisticated application behavior.

But, is this design paradigm really necessary? Why do you need to know if a client's session has timed out, unless they are making a new request? Do you plan to revoke permission to view content that your server already delivered? Nimur (talk) 23:33, 10 January 2012 (UTC)

Well, the thing is, that this is part of a larger application, and the design is that every session allocates a resource from inside that application and starts a thread to periodically monitor that resource. I can't just keep on allocating resources and starting threads and be done with that, otherwise the server will run out of memory. Luckily these threads already know how to free their resources and stop running, they just need to be told when to do it. Therefore I figured it would be best to do that immediately when the user's session expires. JIP | Talk 19:19, 11 January 2012 (UTC)

It seems that the trivial solution is to use a watchdog timer. In other words, pick a reasonable session timeout constant (say, ten minutes - you can obviously tune this to meet your performance and usability needs). Always terminate a session after the timeout. Design your system so that any user-action resets the server-side countdown back to zero. Nimur (talk) 22:28, 11 January 2012 (UTC)

January 11

regex problem

I'm cleaning up a very large text file which contains heaps of entries like

[123] 

ie. a number between 1 and 999 inside a pair of square brackets and followed by a space. I just want to remove (not replace with anything). Can someone advise some regex code for this? Moondyne (talk) 07:22, 11 January 2012 (UTC)

What form of regex/what language/application? For Perl, something like

s/\[[0-9]{1,3}\] //g

should work. --Colapeninsula (talk) 10:49, 11 January 2012 (UTC)

No joy. The text is here if you want to do it for me ;) Moondyne (talk) 11:21, 11 January 2012 (UTC)

Done using \[[0-9]*\]\s* in Kate (text editor). -- kainaw™ 14:02, 11 January 2012 (UTC)

Thanks guys. Moondyne (talk) 14:12, 11 January 2012 (UTC)

report of censoring by Wikipedia Chinese web site

Dear Sir or Madam,

I wrote the Legal History of Chinese Americans in Chinese and tried to upload it onto Wikipeida Chinese web site. My content keeps getting deleted. There was a vague statement that I some how violated some one else's copyrights on "China American History" just a day before my posting, and when I clicked on that link, there was nothing.

Since this is a free web site,I hope the Chinese pages have no censorship. Please let me know what to do. Thanks.

Chang C. Chen — Preceding unsigned comment added by 220.136.184.232 (talk) 10:16, 11 January 2012 (UTC)

You were trying to post on Chinese Wikipedia at http://zh.wikipedia.org/wiki/ rather than the English Wikipedia? Each Wikipedia has its own administration, help desk, etc, so you will have to ask there, not on English Wikipedia. All versions of Wikipedia take copyright violations very seriously and will remove all content that appears to infringe anyone's copyright. Occasionally mistakes are made and it may be that your work did not infringe copyright, but you will have to take it up with the administrators on Chinese Wikipedia.

Chinese Wikipedia is run by Wikimedia foundation in the USA just like other Wikipedias, and does not censor discussion of controversial topics. The only censorship is the same rules as other Wikimedia sites, which prohibit libellous content, copyright violation, and a few other equally illegal things. For this reason it has frequently been blocked by the Chinese government. --Colapeninsula (talk) 11:01, 11 January 2012 (UTC)

If your content appears to have disappeared, click the "View history" tab at the top of the page of interest and look through the entries (or the Chinese equivalent if you are using the Chinese Wikipedia). You should find your contributions, and if they have been removed, you should be able to see where, and hopefully a supporting edit summary stating why. If there's nothing in the history about your additions, then you probably forgot to save the page when you added your content. If you cannot actually access the page at all, then it's probably being blocked by the Chinese Govt censors (who do block many Wikipedia pages, even when not blocking the whole site). --jjron (talk) 15:12, 11 January 2012 (UTC)

How do I use phpMyAdmin

Ive installed php mysql and phpmyadmin by following instructions I found on the web but now i don't know how to start it. --212.120.242.42 (talk) 10:25, 11 January 2012 (UTC)

phpMyAdmin is just a PHP script that uses MySQL, so you don't need to start it if PHP and MySQL are already running correctly. You just need to put it into whatever directory your server recognizes are a "web" directory that it should be parsing for PHP, and it should work. --Mr.98 (talk) 12:18, 11 January 2012 (UTC)

You don't start PHPMyAdmin. It is a web page. You go to the web page (which is completely dependent on exactly where you installed the scripts). -- kainaw™ 15:17, 11 January 2012 (UTC)

pagefile

Would installing an internal hard drive into a computer and setting the pagefile in Windows 7 to something absurd like 750GB greatly improve system performance? The new hard drive would have nothing on it except the pagefile 82.45.62.107 (talk) 12:38, 11 January 2012 (UTC)

No, almost certainly not. If you're paging, you've exhausted your memory and you're in the hell of swapping. A faster drive to swap to just makes that hell slightly less, um, hellish. But it still sucks, and you want to do whatever you can to not be paging in the first place. If you're in danger of swapping, buy more RAM. -- Finlay McWalterჷTalk 12:47, 11 January 2012 (UTC)

While it's true you want to avoid relying on a page file and a 750GB page file would serve no purpose, it questionable if you want to do whatever you can to do not be paging in the first place. As was discussed recently, Windows will commonly put stuff to the page file even if you have a lot of RAM since it considers it better to use the RAM for cache (and possibly other things like Windows Vista I/O technologies#SuperFetch) which may be used, rather then use it keeping stuff in RAM which hasn't been used for a while. As I remarked, you get little ability to control this (other then something stupid like disabling the pagefile) in Windows, I believe more in some of the *nix OSe,s but I don't think you can say it's clearly a bad strategy for everyone. There is a reason why Microsoft (and actually I believe many *nix distros by default [4]) chose it.

Except in extreme cases there's a good chance you're going to have less RAM then data that may be required sometime soon (and caching generally means you need a lot of stuff that isn't used to ensure the stuff that is used is available). Particularly if you're the sort of person who opens programs which you then don't use for a while, it may very well give you a better overall experience to move that program data out of RAM even if you have to take a speed hit when you go back to it. (Of course there's also a question of psychology, some people may feel annoyed when they have to wait 10 seconds for a program to become available while the program data is reloaded, even if they haven't used it in 10 hours and in that time have saved 2 minutes of waiting from cache that was only there because of the RAM freed up from that program. This isn't completely surprising since when you're waiting for an open program to become responsive, it's fairly obvious but it's not obvious that you didn't have to wait so long because something was already in RAM.)

BTW not that relevant here but [5] and [6] appear to confirms what I speculated in December 29th which is that Windows will always try to keep a copy of everything in RAM on disk if possible (obviously stuff like cache already has a copy) so that can easily free up RAM when necessary.

Nil Einne (talk) 13:36, 11 January 2012 (UTC)

Regarding your last paragraph: the top-voted commenter in the first thread you linked seems kind of confused. He says "windows likes to keep a backing store in the page (swap) file for everything in your physical memory. [...] The downside is slower load times [...] as the item must be both read from disk to RAM, and then the RAM written back to disk". That's wrong. All paged physical RAM is backed by some disk file, which may be the page file or some other file. When it's backed by the page file it's called "virtual memory" and when it's backed by some other file it's called "disk caching" or "memory-mapped file access", but it's basically the same thing internally. When a page in RAM is dirty (meaning that it's been modified since it was last loaded from disk), and the page hasn't been modified for a while, and the disk is idle, it makes sense to write the new contents out to the backing file, after which the in-memory copy can be marked as clean. All modern operating systems do this. Writable data segments of executable files are a special case: they're mapped copy-on-write, meaning that if they get modified they morph into new pages backed by the page file. But until they're modified they remain backed by the executable file. No operating system will waste time writing an unmodified page to disk when there's already a copy on disk in a known location. -- BenRG (talk) 03:03, 12 January 2012 (UTC)

I found a cute cooking illustration of the huge increase of latency that going to disk entails. If cache is the refrigerator, and memory is your neighbor's house, then fetching something from disk involves driving around the world. It's good argument for getting a larger neighbor's house. I believe that, in general, having a larger swap file never makes your computer faster, it just allows it to thrash longer before the OOM killer goes on a rampage. Paul (Stansifer) 16:40, 11 January 2012 (UTC)

From this illustration:

Typical CPU is 120 million times faster than typical memory

Two minutes to access main memory Go to the neighbor's house to get an item.

Surely they mean 120 times, not 120 million times? JIP | Talk 20:41, 11 January 2012 (UTC)

Hm. I don't think it's either of those. There are 1 million nanoseconds in a millisecond. If you have a HDD seek time of around 10 milliseconds and a memory read time of 100 nanoseconds, random reads should be 100,000 more expensive for disk than for memory. So that should be the difference between 2 minutes and 4.5 months. Paul (Stansifer) 21:17, 11 January 2012 (UTC)

The text I quoted was about CPU vs. memory, not about memory vs. hard disk. JIP | Talk 21:22, 11 January 2012 (UTC)

Apparently, I can't read. You are correct. Paul (Stansifer) 21:36, 11 January 2012 (UTC)

Columns in EPUB

Hello,

I am presented with the task of converting a novel from InDesign to EPUB. All is straightforward apart from one section which has non-standard typography. For a start the left hand page and right hand page need to be read concurrently - the section is presented as two people experiencing the same events, but the person on the left hand page has gone mad and the text jumps about the page, while the right-hand page continues normally.

On an ereader, is there a way to present: a) text in fixed columns so that they remain together and b) non standard typography - changes in size, orientation, font, opacity etc?

Any help appreciated 195.60.20.81 (talk) 16:49, 11 January 2012 (UTC)

This video tutorial (which I confess I've not watched) claims to cover text positioning in EPUBs created in InDesign. I believe this kind of thing is actually done in CSS. -- Finlay McWalterჷTalk 17:17, 11 January 2012 (UTC)

Skype on smartphones: 3G or wifi

Which way does Skype use on smartphones: 3G, wifi or both? 88.9.214.197 (talk) 20:28, 11 January 2012 (UTC)

On my Android phone it will work over either. -- Finlay McWalterჷTalk 20:36, 11 January 2012 (UTC)

How can a web crawler see what we can't?

A month ago a message board web site announced it would be closing and referred its members to Facebook and Twitter. Some of us wanted to still be able to read what was on those boards, but three days after new posts were disabled on most parts of the site and one day after the last section had new posts disabled, using any URL on that site resulted in being forwarded to the list of Facebook and Twitter links. Members of a site where some of us went after the shutdown were informed we could see cached versions of the pages in search engine results. But I discovered something amazing when I tried this: there was a date when the closed site was last crawled. It was a date on which we could not access the old site because we got forwarded. I even tried the Wayback Machine. It had not done much, but when a related message board shut down, and was visible for three months, a lot of new stuff got archived and I didn't know it until months after I could no longer access the old site.Vchimpanzee · talk · contributions · 21:35, 11 January 2012 (UTC)

A lot of forum systems distinguish between "real" users and search engine bots (typically by user agent string). The idea, I presume, is to help search engines index a forum and entice in visitors to become new members, etc.. Frequently "private" or "disabled" forums are only so for "real" users, most likely because typically the forum admin isn't aware of this search engine UA exception. ¦ Reisio (talk) 21:43, 11 January 2012 (UTC)

It's actually quite easy to spoof your user agent. You would basically be masquerading as the search engine crawler. If you're using Mozilla Firefox, I recommend [7]; for other browsers, Google is your friend. --NYKevin @286, i.e. 05:51, 13 January 2012 (UTC)

Best program for a text-based shooter game

Hey, I've never coded before, but I am willing to learn any language. I want to know what language would be best for a game like this:

It would be text-based, and involve the player choosing from a selection of classes. The classes would have different hp counts, weaponry, and clearance levels. They would also choose a race, which would only affect the types of armor they can wear (it's sci-fi themed.)

The player would advance through rooms by fighting randomly-generated opponents and occasionally gaining randomly-generated allies. (randomly-generated = they'd choose from preset NPC classes and races). Fighting would involve range, initiative, and at one point fighting an invisible boss.

I'd also like it if the player could choose their name/gender at the beginning, and could nickname allies as they join the party.

This seems like a pretty simple game to make, but what coding language would be the best choice to learn? I tried Inform 7 but it didn't seem to be advanced enough to allow for some of these aspects. 128.111.81.41 (talk) 22:02, 11 January 2012 (UTC)

I suggest you read Text-based game, and decide on which of the genres described there best match your vision. The programming language you use will be different for a roguelike game or a text adventure game. If you intend it to be multi-user or in real-time, that will also make a difference. If you are simply thinking about a single-user text adventure, with some random monsters and perhaps some computer-based companion characters, I suggest one of the Z-machine interpreters would be best.-gadfium 22:59, 11 January 2012 (UTC)

We had a similar question a while ago. One suggestion was one of the programmable MUD engines, in particular LPMUD with LPC for programming. It has the added benefit of free support for multi-player network play. --Stephan Schulz (talk) 23:13, 11 January 2012 (UTC)

One thing to bear in mind is that getting comfortable with a programming language takes quite a while - you might want to choose a language that you think you might find useful for other projects in the future (in particular, Inform makes it very easy to write text adventure games, but isn't really much use for anything else) - although many of the skills you learn will be transferable to other languages anyway. Whatever you choose, you will probably want to find a good book or online tutorial and spend a little time getting used to the basics before you start coding your game, and it would be a good idea to choose a bare-bones subset of the game and get that working before you start adding all of these features. 130.88.99.231 (talk) 19:27, 12 January 2012 (UTC)

I would also suggest that you look for an open-source game similar to the one you want to write and try tweaking the code or adding a new feature. This is a great way to learn.-gadfium 22:56, 12 January 2012 (UTC)

January 12

"Can't extract MFC42.DLL"

My computer has two issues:

• The battery does not charge. I don't know why - I've bought two batteries for this computer, and the second one doesn't work either. I tried checking the service tag in the BIOS, but it is properly set. My understanding was that the service tag must be properly set.
• I downloaded the latest BIOS from Dell. However, it does not work: when I tried running it from the command prompt in administrator mode (Vista), it says Can't extract MFC42.DLL. It does not give any message at all when I run it not from the command prompt.

I was hoping to fix the first problem with the second. (anonymous) 00:03, 12 January 2012 (UTC)

And just to clarify I downloaded MFC42.dll from support.microsoft.com and put it in the same directory but it still is coming up with that message. (anonymous) 00:20, 12 January 2012 (UTC)

Have you (or, are you able to) tried using a different charger? Dell laptop chargers have a chip which tells the computer that you are using a 'Genuine Dell Charger' - and if you are not, the battery will not charge. I believe you would normally see a message on startup if this was the case, though. However, if you know someone else with a Dell laptop, try using their charger before playing with the BIOS - it just might work! - Cucumber Mike (talk) 01:24, 12 January 2012 (UTC)

Upgrading RAM while hibernated

I recently added more RAM to my Windows 7/Xubuntu dual-boot PC. On booting, Windows reported that it could not resume the hibernated session because \HIBERFIL.SYS was invalid; I assume this is because the new memory was unaccounted for. Does an analogous problem occur with hibernated sessions in Linux? Has anyone built a tool that can update hibernated sessions after a RAM upgrade? NeonMerlin 00:09, 12 January 2012 (UTC)

I might be wrong old chap but I would suggest if you are going to make a physical change to your system to do a full shutdown first so that Windows has a chance to detect new hardware during the bootup sequence and install any drivers etc it needs to run it when it reboots from scratch? Quintessential British Gentleman (talk) 00:21, 12 January 2012 (UTC)

My bet is that, if anyone were to build such software, you'd need to restart the computer to install it... (because it would interact with the kernel) Paul (Stansifer) 01:45, 12 January 2012 (UTC)

It's hopeless to alter the hibernation file to give immediate access to the new RAM, because there are undoubtedly many different internal data structures that are initialized once per boot under the assumption that the amount of RAM is fixed. It may be hopeless even to make the hibernation file bootable (using only the old amount of RAM) because of the complexities of mapping RAM chips and memory-mapped IO zones into the "physical" address space, and it would be pretty much pointless since you'd have to shut down and restart anyway to complete the upgrade. If you just want your lost hibernated state back, and you haven't otherwise booted Windows since then, it will boot if you restore the original RAM configuration. I know because I made this same mistake once. -- BenRG (talk) 16:32, 12 January 2012 (UTC)

This is pretty much why I never put my computers to hibernate. The only way around it is take the new ram out, reboot the system, shut it down fully, fit the ram, and boot it up with all the ram. Mrlittleirish 16:03, 13 January 2012 (UTC)

Average amount of time for two-qubit entanglement.

I was wondering if anyone knows what the average amount of time is for an entanglement of two-qubits. I would have to assume that the amount of time is longer than say for seven qubits. This question is obviously about quantum information science. Thanks. This is the second time I'm asking this question by the way. Lighthead ^þ 03:24, 12 January 2012 (UTC)

What's with the eerie silence? Nobody knows about qubits? Lighthead ^þ 03:06, 13 January 2012 (UTC)

No, sorry, I don't know anything about qubits. I do know stuff about DJ Qbert and the game Q*bert. I googled around a bit but everything I could find was too complicated for me to understand. Von Restorff (talk) 03:51, 13 January 2012 (UTC)

That's funny... thanks for trying at least. Yeah; it can get pretty complicated. I thought I was unofficially being blacklisted because I started trouble here on Reference desk one time. Pheww! What a relief! Lighthead ^þ 05:50, 13 January 2012 (UTC)

As far as I'm aware, we don't blacklist people from asking sensible questions, unless they're site-banned or something. As for qubits, I'm vaguely familiar with quantum computing but I honestly wouldn't know where to begin with that question. --NY

Kevin @292, i.e. 05:59, 13 January 2012 (UTC)

It's been a while since I've studied quantum things, but I may be able to help. However, I'm not sure what you mean by average time for an entanglement; if you can help me, I can probably help you :-) Phoenixia1177 (talk) 12:49, 13 January 2012 (UTC)

Like the majority here (and in the computing world) (but possibly unlike Phoenixia1177), I know next-to-nothing about quantum entanglement of qubits, and I can't find anything in Wikipedia about time of entanglement of Bell states. Can anyone else find an appropriate article? (Greenberger–Horne–Zeilinger states and W states involve three qubits, and there is no mention of entanglement time there either.) Dbfirs 17:51, 13 January 2012 (UTC)

Looking for a 3d First Person Shooter/Engine/Game Making System that Allows Tinkering with Enemy AI

I recently started playing Bioshock and started thinking about the AI in the game, specifically the dynamic between npcs that can end up engaging in conflict and goal based behaviour, which leads me to wanting to experiment with more elaborate versions. However, I do not have the time, or the graphics ability, to program a shooter from scratch just to experiment with enemy ai (and doing a program that just relays results of what would happen lacks the fun of something you could actually interact with) Thus, I'm looking for some system/game that would let me design custom levels and enemies; the more flexible the better. I don't care about graphics (I'd be happy with Wolfenstein/Doom era, or even polyhedra moving about in 3d), though if it does use advanced graphics, I would need there to be a decent ammount of existing resources. Finally, I have no preference in programming language or complexity, so long as a basic framework is already in place; I would also be happy with a pc game that had the ability to build sufficiently custom levels. Side Note: My question reads a tad on the ill defined/rambling side of things, if anything is unclear, please let me know so that I can elaborate/clarify. Thank you in advance for any help:-) Phoenixia1177 (talk) 08:18, 12 January 2012 (UTC)

This is the op, around a $100 is the most I would be capable/willing to pay for this, I am not looking to make an actual game and don't require any type of license and would like to be able to use free existing graphics. 209.252.235.206 (talk) 09:09, 12 January 2012 (UTC)

I don't quite know if it's what you want but Garry's Mod has programmable scriptable NPCs, which you can program in Lua. It's probably a bit simple for what you want but it's very cheap. http://wiki.garrysmod.com/?title=Basic_Scripted_NPC has some info plus the forums at facepunch.com 192.84.79.2 (talk) 10:03, 12 January 2012 (UTC)

I'm not really into modding, but the source code to Quake, up to to Quake III Arena, is under the GPL, and OpenArena seems to be an entirely free game build around this. Alternatively, Half-Life and its descendant Counter-Strike are heavily modable and have huge mod communities. I assume this also enables changes to the AI, but don't know to what degree. --Stephan Schulz (talk) 10:05, 12 January 2012 (UTC)

Possibly helpful could be Unity (game engine). fredgandt 11:54, 12 January 2012 (UTC)

Thank you all very much for your responses:-) All of these look interesting (now I have something awesome to work on this weekend!) Phoenixia1177 (talk) 10:17, 13 January 2012 (UTC)

every time i search the web my internet explorer stops working what can i do to fix this problem?

every time i search the web my internet explorer stops working what can i do to fix this problem? — Preceding unsigned comment added by Jake.edu (talk • contribs) 18:04, 12 January 2012 (UTC)

Run the fixit thingy. If nothing else works download malwarebytes free and scan your computer. If that does not work either then run the System File Checker. Von Restorff (talk) 10:25, 13 January 2012 (UTC)

What are you using to search the web? What version of Internet Explorer are you using? What add-ons (yes, even all those fancy toolbars) have you added? -- kainaw™ 19:32, 12 January 2012 (UTC)

Why stay with stone tools, many people have now switched to more popular browsers. --Aspro (talk) 20:05, 12 January 2012 (UTC)

Err, "popular" is probably not the right modifier there. IE is still the "most popular" browser out there by market share for desktop computers. It's gotten less popular over the years, but it's still the most popular. --Mr.98 (talk) 22:50, 12 January 2012 (UTC)

Perhaps Aspro meant to speak of popularity within a specific cohort, excluding people who, for instance, refer to email as 'the email,' like my dad :) DRosenbach ^{(Talk | Contribs)} 23:52, 12 January 2012 (UTC)

I didn’t have the benefit of you young folk that learnt all this high faluting new mathematics that can prove less-is-more etc., but in my day this graph would suggests that IE had less than 50% and hence the less popular. Not withstanding also, that many browser are set to report themselves as being IE so as to access IE only sites. (Graphic linked because it is huge and a bit OT) But then again, all this, is from Wikipedia and who believes anything on that website. However, I am willing to sit (not stand) and be corrected. --Aspro (talk) 00:42, 13 January 2012 (UTC)

Oh, and as Drosenbach hints at, the WP cohort is 34 %.(ditto). Note: the OP asked on WP ref desk and so he is one of us (this cohort) – one must presume... And still using neolithic apps. Thats all I'm saying!--Aspro (talk) 00:53, 13 January 2012 (UTC)

If you are considering it IE vs. everything else, then it's less popular. But if you consider it every browser for themselves, it's IE as the most popular. If I said that apples were the most popular fruit, you wouldn't assume that I meant that they were more popular than the sum of the popularity of all other fruits put together, would you? But anyway, we're getting off topic here. I've shrunken those graphs to links — they're distracting from the actual question-answering. --Mr.98 (talk) 03:04, 13 January 2012 (UTC)

popular is not the same as frequently used. IE users generally never made a choice to use that particular browser. Von Restorff (talk) 10:19, 13 January 2012 (UTC)

I would phrase it differently: they never made the choice to use a different browser than IE. --Ouro (blah blah) 17:53, 13 January 2012 (UTC)

The difference of TouchWiz and Android?

Hello, I'd like to know what TouchWiz does, and how would Android acts if it'll be deleted from a Galaxy phone. Does it control over the "relation" of the touchscreen and the kernel? Exx8 (talk) 23:27, 12 January 2012 (UTC)

Reading the TouchWiz it sounds like TouchWiz is primarily a launcher (that is, it's the thing that runs when the phone starts, and it's from TouchWiz that you start other apps). If TouchWiz is anything like HTC Sense (which is what HTC brand Android phones use for that task) it's also responsible for desktop widgets, notifications, and locking the screen. It's possible to install other apps that function as a launcher too (some are listed here). I don't know if you can remove TouchWiz altogether, but you can try a different launcher. -- Finlay McWalterჷTalk 00:00, 13 January 2012 (UTC)

Note that my "launcher" link above is for the equivalent thing for Windows; I don't think we have a summary article for Android or iOS launchers. -- Finlay McWalterჷTalk 00:08, 13 January 2012 (UTC)

Googling suggests that TouchWiz can be disabled (if not actually removed) on some but not all phones. If you disable it you get the standard Android launcher (by Google), which is not much different. -- BenRG (talk) 02:44, 13 January 2012 (UTC)

Embedding a video into PPT 2003

I would like to embed a 1-minute segment of Spaceballs into a PPT and I use the 2003 version (because I like it the best). I have the film in avi format, but after finding instructions online about how to embed it, it comes up with audio but no video. The 1-minute segment is a very comedic one, and is featured as 3 different youtube videos, and I watched a youtube video showing me how to embed such a youtube video into PPT, but all 3, when clicked on to begin playing in PPT format, say 'embedding disabled by request -- please visit youtube.' So I think I'm back to my film in avi format -- does anyone know how I can embed it with audio and video, and also perhaps if I'm able to do just the 1-minute segment, rather than having to find the place and stopping it after a minute. Thanx! DRosenbach ^{(Talk | Contribs)} 23:50, 12 January 2012 (UTC)

I can help you with the one-minute bit - use a simple editing tool like VirtualDub, cut out the portion you'd like to embed, save it to a separate file. --Ouro (blah blah) 07:28, 13 January 2012 (UTC)

http://support.microsoft.com/kb/885915 Von Restorff (talk) 09:55, 13 January 2012 (UTC)

January 13

Split files unrecognized

So I downloaded a movie and it was 10.1 GB, mkv format. The original opens fine using VLC and quicktime. I wanted to split it into smaller parts so I downloaded an application, "pif splitter". I successfully split the file into ten parts. The parts are each named name001.mkv, name002.mkv and so on. However when I try to open any of those with VLC I get an error message: "No suitable decoder module. VLC does not support the audio or video format "undf"". When I try to open any of them with Quicktime I get the message "...is not in a format that Quicktime understands". I though "okay, this splitter didn't work right let me try another." So then I downloaded "split@concat". That program likewise successfully split the original into ten parts. However, I am getting the same error messages when I try to open them. So I guess even though it's keeping mkv in the name it's not actually keeping the format? Something else? Can anyone explain what I'm doing wrong or what I can do?--108.46.103.88 (talk) 01:44, 13 January 2012 (UTC)

The purpose of a file splitter is to allow you to move the file to different media, which may have size limitations (eg, some file systems have a 4 GB file size limit; single-sided DVDs only take 4.something GBs). You might use such media in the process of copying your big file to another computer. To actually use the file, you need to rejoin the pieces back to a single file again. Each program to split a file will come with a method to rejoin the results.-gadfium 01:52, 13 January 2012 (UTC)

To split a video so that the chunks can be opened separately, you'll need an MKV-specific tool. Google:MKV splitter. NeonMerlin 01:59, 13 January 2012 (UTC)

Thank you NeonMerlin. That's very helpful. Gadfium there must be other people whose reasons for splitting is otherwise. Me, I want to burn to dvd but standard disks won't allow files of large sizes.--108.46.103.88 (talk) 02:40, 13 January 2012 (UTC)

Ya, as merlin said I think the MKV format doesn't deal well with arbitrary splits. Other containers seem to handle it. Depending on your uses, different formats might be more appropriate. Shadowjams (talk) 07:34, 13 January 2012 (UTC)

Quantum OpenCL?

How does the performance of a classical computer simulating a quantum computer tend to compare with that of a classical algorithm solving the same problem? Would it be practical for a quantum programming language to converge with OpenCL to help make quantum and classical computers interchangeable to the programmer? NeonMerlin 01:49, 13 January 2012 (UTC)

Let me start with saying I don't know anything about OpenCL. However, a classical computer simulating a quantum computer would still be doing classical computation and, thus, would be running a classical algorithm. Are you asking, perhaps, how classical algorithms that attempt to be "quantum" compare to one's that don't? From the phrasing of your question and that you seem to be asking if programming languages can make quantum and classical computation interchangeable on a single device, but quantum computation is quantum computation because of the physics of the device, not any abstract elements of the programming language. Or do you mean to ask if OpenCL could be used to program in parallel a quantum and classical device? It looks like you are crossing the roles of algorithms and physics in your question, is there some specific thing you are considering that might help to clarify this? Phoenixia1177 (talk) 10:15, 13 January 2012 (UTC)

I think the question is just whether quantum algorithms running in a quantum-on-classical emulator perform as well as classical algorithms. I'm not sure, but I think the answer is a strong no for known algorithms (which includes known emulation algorithms). For example, the quantum part of Shor's algorithm involves finding the period of a^x mod N with a QFT, where N is the number to be factored, and I don't think a classical emulation will do better than O(N) on this, making the algorithm worse than trial division. But it could be that the "real" answer is yes, with as-yet-undiscovered quantum and emulation algorithms. -- BenRG (talk) 18:34, 13 January 2012 (UTC)

Quantum computing is not "pin-for-pin" interchangeable with parallel computing. OpenCL doesn't seem to be the optimal language set for the best expression of quantum algorithms. Nimur (talk) 18:31, 13 January 2012 (UTC)

Can you blackout jan 18 to protest the SOPA act?

i love wikipedia, actually one of my friends father met with one of the fouders, my friend is kiran sonty from boyton beach florida, anyways, this site has so much information and i think it will really have a big effect on people if they seen this site closed down, reddit is huge but wikipedia is bigger, it will be much appreciated and it would be so cool to see that real people control the internet, pelase consider — Preceding unsigned comment added by 174.61.66.210 (talk) 18:22, 13 January 2012 (UTC)

That would be a clear-cut case of breaking Wikipedia to make a point. I do not believe there would be traction in the Wikipedia community to intentionally disrupt Wikipedia in order to make a political point, irrespective of the validity of the point, even if the stance has (hypothetically) widespread consensus approval among Wikipedia contributors. Nimur (talk) 18:29, 13 January 2012 (UTC)

I believe that most Wikipedia users would strongly disagree with any attempt to take down an international resource because one country is discussing a law that is very similar to ones already in force in Denmark, Finland, Ireland and Italy. -- kainaw™ 18:34, 13 January 2012 (UTC)