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March 14

Sign language annotation for sound files

For File:Sextortionagent_interview.ogg I was wondering if the software supports a sign language annotation for the sound files, indicating what signing would be done if one used American Sign Language. I think that having sign language for audio files could be another way to add support for deaf users (some instructional videos and news broadcasts use sign language) WhisperToMe (talk) 08:01, 14 March 2013 (UTC)

That seems unnecessarily complicated. I guess there could be better encouragement and support for linking to a transcript if it exists when a sound file is referred to, in this case there is a transcript at File:Sextortionagent_interview.ogg#Introduction and transcript (original English). The place to put an idea like that would be I'd guess WP:VPR. Dmcq (talk) 09:46, 14 March 2013 (UTC)

Alright, I'll use the village pump. Yeah, there are some videos that use sign language instead of subtitles even though subtitles seem simpler... WhisperToMe (talk) 14:16, 14 March 2013 (UTC)

motion detection for computers

how would I go about setting up a program to detect motion through a web-cam or similar and use that to control the movement of my computer's mouse pointer? and would I need any more advanced hardware or would my current cheap, simple camera be good enough to interpret 2D gestures across the screen?

Kitutal (talk) 13:01, 14 March 2013 (UTC)

Computer vision is not an easy problem, and there are no "cookbook" solutions. There aren't a lot of great software programs that work "out of the box," either.; though there are plenty of tools. You can make this problem a little bit less insurmountable by:

• using an existing high-level language like MATLAB, or a powerful API, like OpenCV, to abstract implementation details so you can focus on algorithms
• simplifying your scene - by using controlled scenes, good lighting, and high-quality cameras, or using standard tricks like brightly- and uniquely-colored targets with simple geometries.

Here's a link to lecture notes from Introduction to Computer Vision at Stanford. A few years ago, some teams made a "Kinect"-style motion tracker for the class project. I'll see if I can dig up a video or paper. Nimur (talk) 14:58, 14 March 2013 (UTC)

Are you asking about finding an existing program, or writing your own ? In either case, I'd be sure to have a sensitivity setting. For some applications, like turning on lights for 5 minutes when motion is detected, a low threshold is fine, while for other applications, like sounding an alarm, that would be bad. StuRat (talk) 15:38, 14 March 2013 (UTC)

Another link, "Introduction to Computer Vision", which has more of its lecture-notes available to the general public. Nimur (talk) 17:29, 14 March 2013 (UTC)

I was hoping for some existing software and/or hardware, otherwise I would need to look up some idea of how to go about creating the stuff myself, or so I can show friends what to do to help. I thought it best to rig up something simple that didn't work wonderfully and attempt to refine that through various methods, including better programming, better camera and the tricks mentioned above, rather than trying to do the whole thing perfectly first time around. Kitutal (talk) 12:06, 15 March 2013 (UTC)

Here's another slide-deck, Introduction to OpenCV. And here's a blog-post including a video of one of our classmates' final project, two-camera motion-capture system used to control a PUMA robotic arm. As you can see, they used bright targets (they taped orange and red color swatches to their hands) to make their program much simpler. For perspective, this required three graduate students and several weeks to design, implement, and tune. As above, the tools exist, but few are "ready to go" out of the box. Nimur (talk) 23:21, 16 March 2013 (UTC)

OK then, where can I go to learn everything I would need to know to do something like that? Kitutal (talk) 23:17, 17 March 2013 (UTC)

Stanford Engineering Everywhere has several classes that are directly relevant, including the Introduction to Robotics course. MIT's OpenCourseWare has dozens of classes that are relevant, including Machine Vision. Nimur (talk) 17:38, 18 March 2013 (UTC)

casses

is there any computing classes on the shanill road belast 13 — Preceding unsigned comment added by 62.253.58.255 (talk) 15:40, 14 March 2013 (UTC)

Belfast Metropolitan College has ICT classes which are held at various campuses around the city, including Chichester Avenue and Whiterock Road. -- Finlay McWalterჷTalk 15:49, 14 March 2013 (UTC)

Why can't you root iOS?

I have an Android and I have come to appreciate the great community involvement in the project in creating custom ROMs that are often much faster and feature packed than both Stock Android and various skins such as Touchwiz. If I understand correctly, the reason that there are no custom ROMs for iOS is because you can't root the devices? Is this purely a technical reason in the sense that developers have been unable to root the phone?

Would it be safe to say that if Apple opens up the phone and allows third party ROMs that there can be a lot of speed and performance improvements from third party devs like Android? Acceptable (talk) 16:15, 14 March 2013 (UTC)

A fully jailbroken iOS device allows the user the same totality of control that a rooted Android phone does, so the premise of your question is false. As a practical matter, developing an alternate firmware to run on an iOS device is much harder than for Android, because much of the software on a typical Android phone is open source and so available for re-compilation and alteration, whereas essentially none of iOS is. Perverse as it may seem, it's possible to run Android on jailbroken iOS hardware: see e.g. http://www.idroidproject.org, although that port isn't complete yet. -- Finlay McWalterჷTalk 16:45, 14 March 2013 (UTC)

Why can't developers just "hack" the non-open source software of iOS? My understanding of operating systems is limited, but is it not just a bunch of files? If it's because the OS prevents users from editing these files, can developers not just brute force or break the encryption or something? Or is this too technically challenging to do? I guess, in other words, if I bought an iPhone, isn't the code and all the files for the operating system already on my device? Acceptable (talk) 22:42, 14 March 2013 (UTC)

Jailbreaking breaks the encryption. But iOS, and its associated apps, is chiefly written in Objective-C (with some C), a compiled language. So what's on the phone is a bunch of Mach-O format binary executables, where the readable Objective C code has been compiled into thoroughly unreadable machine code. Patching that is a hideously laborious process, and decompilers produce fairly horrible results that aren't much better. Beyond removing some of iOS's security features, it's not worth the bother exploring all its depths. -- Finlay McWalterჷTalk 22:54, 14 March 2013 (UTC)

Oh I see, is this similar to Adobe Flash whereby the files that you edit on is the .FLA while the compiled version is the .SWF? Theoretically, would it be possible for an Apple engineer (who isn't afraid to be sued) to just load all the master files onto a USB and upload it on the Internet? Acceptable (talk) 22:59, 14 March 2013 (UTC)

Yes, and yes. -- Finlay McWalterჷTalk 23:06, 14 March 2013 (UTC)

I have a sneaking suspicion that even if the source code and tools and instructions necessary to engineer an operating system were all made available at no charge and with a fairly liberal license, very few people would actually use them. It probably wouldn't even light up the front pages of the rumor-mill websites if such material was surreptitiously leaked to the internet in a place nobody would look. This is probably because, while "jailbreaking" is frightfully exciting, actually programming at the lower levels of an operating systems is very boring. But, I don't know that much about programming iPhones; perhaps somebody might come along and correct me. Nimur (talk) 03:45, 15 March 2013 (UTC)

Uh, okay. So the only specific page you linked describes how to build clang, which is a compiler. Which is a useful thing to have, I suppose, if you're going to try to recreate an entire operating system from scratch, but... -- BenRG (talk) 04:23, 15 March 2013 (UTC)

I think Nimur is trying to assert that because Apple has released the Darwin kernel source code, the fact there is only limited interest in this demonstrates most people have little interest in the source code. However many would suggest the more likely interpretation is that a kernel does not make an operating system and with the large number of *nix kernels out there (including the ones Darwin was partially based on), it's not particularly surprising that few people were interested in remaking an operating system from the what Apple released (when they felt like it) as OpenDarwin and PureDarwin have shown. In any case, I don't get the relevance of this the OP's question. The OP's question was not why doesn't someone make a new OS for iOS devices (which a operating system based solely on the Darwin kernel would be) but why don't people customise iOS (the existing OS) as much as Android. The fact they can't easily do so because Apple has not released the source code for the operating system remains true whatever bits Apple have released. In fact, AFAIK, the amount of source code available for the iOS builds are minimal (our own article says 'except for the ARM variant, which has not been released in any form separately from iOS'), not even close to the whole kernel, hardware support etc. The fact it's a fork of something that has been partially released isn't likely to help much. I strongly suspect the Android option FM mentioned is still potentially far easier then trying something with what Apple released. And there's no particular reason why they'd want to, few people think there's something particularly revolutionary about the Darwin kernel, it's all the interesting bits of iOS that Apple did not release that people care much more about. (Of course one of Nimur's assertations is probably correct, there is little interest in doing much low level programming of the operating system but as the OP's original question has shown. There is a fair amount of interest in customising it in various ways as the very large number of highly custom Android firmware mods have shown. In fact many of those cases where e.g. sometimes the developers have had to at least partially reimplement hardware support due to the company not releasing it has shown people are even willing to go down to the nitty gritty when necessary. But as I said earlier, people need a lot more then what Apple released to be able to do this.) Of course when Apple does release something that's useful (whether entirely their own work or not), people may use it as WebKit showed. Nil Einne (talk) 07:22, 15 March 2013 (UTC)

Nil, have a paragraph break, on me: ¶. :-) StuRat (talk) 14:55, 15 March 2013 (UTC)

Windows 7 Shutdown Strategy

I'm looking for a way to use the shutting down of my laptop to enforce a solid sleep schedule. For a while, I was using a windows scheduled task to start up shutdown.exe /s on a five minute repeat for an hour. This was fine until I realized I the task could be disabled. I am currently trying out the 30 minute random delay, however that degree of variation is not ideal, and it would be better if it were narrower.

Ideally, I'd like to be able to have a scheduled log off time at night that can only be edited during the morning/day, though I don't know if windows or any other program would have that functionality. I also briefly considered setting up a "on task creation/modification" trigger to the task, which would likely prevent any changes to the task without getting the intended result, but I am wary of setting up scheduled tasks that I cannot change (such as a shutdown at log on task, I don't know how that would be bypassed). If anyone has experience with this sort of thing or any suggestions, I would greatly appreciate it. Thanks. Sazea (talk) 16:23, 14 March 2013 (UTC)

I'm not entirely sure I understand what you're trying to achieve. It sounds like you're trying to set things up so that the computer will shut off at night (so you're not awake until 4am playing Skyrim or something), and you're worried that your 4am self will just disable the software your daytime self has installed? The trouble is that it's the same administrative permissions you need to install software like this as you need to uninstall or disable it. The best you can do is set yourself up as a non-admin account, setup the schedule as admin, and then have some other person change the admin password so that they know it and you don't. You're probably better off with some sleep-cycle management software, if this is a real problem for you (I know people who use SleepCycle on iOS, but I've no personal experience of it). -- Finlay McWalterჷTalk 16:54, 14 March 2013 (UTC)

Computer solutions may not get at the root of the problem, which is why you aren't sleepy enough to want to go to sleep when you should. I suggest eliminating all caffeine after noon (or ideally eliminate it completely) and doing some heavy exercise about an hour before bedtime. Also, avoid computer games where you are penalized for signing off (say if competitors who stay online rank up and you don't). StuRat (talk) 17:16, 14 March 2013 (UTC)

why should we pass object of the class implemented from runnable to constructor of thread class?

Hi my doubt is in java. My doubt is on creating thread by implementing runnable interface. Please see the below programme.

• In below programme I have implemented the class countdowneven from Runnable.
• In main method I am passing the object of countdown even to constructor of thread class.
• Why should we pass the object of countdowneven to constructor of thread class?
• What operations will be performed by Thread class constructor on object of countdowneven?

---

. class thread
{
public static void main(String args[ ])
{
Thread ce=new Thread (new countdowneven());
ce.start();
}
}
class countdowneven implements Runnable
{
public void run()
{
for(int i=10;i>1;i=i-2)
{
System.out.println(i);
}
}
}

---

Output:
10
8
6
4
2
— Preceding unsigned comment added by Phanihup (talk • contribs) 18:38, 14 March 2013 (UTC)

We don't do homework for you, sorry. Those are clearly homework questions. Would you like to know more about Threads? If you're specifically wanting to figure out threads in java, I recomend reading the documentation in the java SDK i kan reed (talk) 19:12, 14 March 2013 (UTC)

Launching the wrong browser

Evert time I have tried to launch Google Chrome in about the last week, my laptop launches IE instead. This applies to all short-cuts, icons, files and lauching it directly from the C:// drive. I eventually got it to launch by running Chrome as an administrator. How can I fix this?--Gilderien Chat|List of good deeds 19:02, 14 March 2013 (UTC)

How are you starting Chrome? If it's by clicking on a .html file, or entering a URL in the start box, then Windows will run the default browser. There should be an option in Chrome to make it check if it is the default. and if not, make it, it. Unfortunately, I don't use Chrome, so I don't know where the option is. CS Miller (talk) 21:10, 14 March 2013 (UTC)

I'm clicking on the Chrome icon, and it is my default browser.--Gilderien Chat|List of good deeds 22:35, 14 March 2013 (UTC)

There has been some suggestion on other sites that it is likely malware. This link recommends running malware bytes (www.malwarebytes.org/). Sazea (talk) 23:34, 15 March 2013 (UTC)

Ok thank you. McAffee seems to have removed it when I ran a full and intensive scan, reporting 5 trojans as part of it. Not really sure how the writer would gain from writing that but anyway ... --Gilderien Chat|List of good deeds 23:49, 15 March 2013 (UTC)

March 15

Modelling software

Hi,

I'm looking for some software to do basic modelling of intracellular processes. This is exactly what I want, but it crashes and the functions don't work, so I'm hoping there's something else out there you can point me too. I'd like to be able to define objects (maybe 10), and define interactions between these objects which occur if they happen to react with each other, generating new objects, which can then interact with more objects. Can anyone help?

Cheers

Aaadddaaammm (talk) 04:38, 15 March 2013 (UTC)

Sounds a lot like Conway's Game of Life. You might want to search for versions of that.

Also, what are your exact requirements. Do you need an animation as output ? If so, would ASCII text be OK, or do you need actual graphics ? What type of interactions would be allowed ? For example: one kills the other, one eats the other (then splits in two), both kill each other, they bind together, they bounce off each other, or they reproduce to make a third ? Also, what happens if three or more meet, and what does one alone do (change direction, grow and reproduce, change into a different type, die of old age, etc.) ? And how big should the grid be (and is it 2D or 3D) ? StuRat (talk) 04:43, 15 March 2013 (UTC)

Um, Game of Life is about cellular automata. This has nothing to do with real-life, biological intracellular processes. I think the OP is pretty clear about what he wants the software to do — model actual biological processes. --Mr.98 (talk) 13:56, 15 March 2013 (UTC)

Did you read the link he provided ? That seems a lot like the Game of Life, particularly that bit about each object moving "North, Northeast, East, Southeast, South, Southwest, West and Northwest". That doesn't sound like real biology. Either does defining 10 objects. You'd want thousands, at the least, to simulate a real system, and they'd need to move in 3D, along any vector, not just the 8 compass directions in a plane. StuRat (talk) 14:48, 15 March 2013 (UTC)

Thanks guys, you're right the thing I'm after is similar to the Game of Life, although more complex. GoL has only 2 states for each position - I'm looking for something with up to 10 states, and these states interact differently with each other. Specifically, I'd like A+B->A+B+C, and D+E->D. And in terms of output, I'm pretty flexible - graphical, data on component concentration vs time, whatever. Aaadddaaammm (talk) 01:27, 16 March 2013 (UTC)

Sounds simple enough to write, if you can't find one already out there. To clarify, is this what you mean ?

"A+B -> A+B+C" means when A and B are on adjacent grid squares, they reproduce, producing C on a third square adjacent to both A and B.

"D+E -> D" means when D is on an adjacent square to E, D kills E.

1) What are the other rules ?

2) How many total organisms, of all 10 types, are allowed ?

3) What's the maximum grid size ?

4) Do you want organisms which hit the edge of the grid to disappear, bounce off, or wrap to the opposite edge ?

5) Do organisms only move 1 grid space per turn, in one of the 8 random compass directions, or can they move at variable speeds ?

6) Can a maximum of one organism occupy a given grid square at a time ? StuRat (talk) 03:55, 16 March 2013 (UTC)

Try Golly (program). It comes with several cellular automatons preprogrammed, and allows basically arbitrary customisation with several ways of specifying the transition function. Golly supports automata with up to 256 states. Careful, though - it's easy to get lost exploring the Game of Live Lexicon included with it ;-). --Stephan Schulz (talk) 11:25, 17 March 2013 (UTC)

Difficulty signing posts

Please be gentle. I can't work out why my posts show as "— Preceding unsigned comment added by Hayttom (talk • contribs)". I'm logged in. I conclude with four tildes. What am I doing wrongly? Your Username 12:28, 15 March 2013 (UTC) — Preceding unsigned comment added by Hayttom (talk • contribs)

It looks like you have messed up your signature in your user preferences (see Preferences link at the top of any page) so it no longer points to your page. Also help type questions like this should go to one of the help pages, see help in the left column - in particular WP:Help desk. Dmcq (talk) 12:57, 15 March 2013 (UTC)

Thanks for both points. Hayttom 13:20, 15 March 2013 (UTC)

Resolved

Firefox redirecting despite two options set not to

I was fiddling around trying to view source for [1] and get immediately redirected to [2] despite having current Firefox advanced option "warn me when websites try to redirect or reload..." and having NoScript set to block meta redirects on untrusted sites. What trick are they using?

Extra credit: This particular newspaper seems to have gotten extremely aggressive about trying to get people to run their crummy scripts, and I'd welcome if someone chased down the "real" URL for this example that contains the actual text in its HTML source. (Mostly I want to know how to do it myself though) Wnt (talk) 16:32, 15 March 2013 (UTC)

There is no source for the first URL: the server sends an HTTP 301 "moved permanently" response containing the second URL. So the browser is doing the only thing it can. -- Finlay McWalterჷTalk 16:39, 15 March 2013 (UTC)

Doesn't this defeat the whole point of these options, which I thought was to warn you before you got sent to some site you don't trust? Wnt (talk) 18:43, 15 March 2013 (UTC)

A "meta redirect" is a <meta> tag within the HTML source. Judging by the name of the NoScript option, it only blocks those. The Firefox option you set also only blocks those. The redirect you got came directly from the web server, not from a <meta> tag. I don't know why the options are set up that way, but it may be because anyone who can manipulate the web server responses can deliver arbitrary data to you anyway from the original URL, so blocking redirects wouldn't help. -- BenRG (talk) 19:15, 15 March 2013 (UTC)

noscript selectively blocks JavaScript, Java, and Flash. They can cause a pseudo-redirect by change the DOM property window.location. As these aren't used in this case, this extension doesn't apply here either. -- Finlay McWalterჷTalk 01:03, 16 March 2013 (UTC)

Re your extra credit: The second link you provided (the address after redirection) does contain the text of the short four-paragraph article in its source, but not the text of the comments.

• If you wanted the text of the article, it is indeed in the source. In addition, you can also go to the printable version (click the Print link which adds ?print=1 to the end of the address). This reduces the page to the article text and nothing else, which will make it much easier to see the article text in the source.

• If you wanted the source of the comments, I found them at the following address: http://echoapi.wpdigital.net/v1/search? [...long parameter list], but the content isn't HTML, I believe it's JSON data.

To find this address, I started a small proxy server utility on my computer and turned on my browser's proxy setting to point to the proxy server. I cleared the browser cache (to ensure the browser had to reload everything), started the proxy server's log, the reloaded the page in the browser. From the proxy server log, I assembled every address the browser requested. Then I looked through the addresses and visited a few interesting ones until I found where the comments were loaded from.

Can you explain more about why you wanted to "chase down the real URL that contains the actual text in its HTML source"? I can't tell if my information above is helpful for what you wanted to do. --Bavi H (talk) 02:32, 16 March 2013 (UTC)

Taking a UK phone to NZ

I wanted some unbiased advice! I have a mobile phone in the UK on the ‘3’ network. I would like to take the phone to New Zealand with me later this year. If I have the phone unlocked, will a SIM card bought in NZ work or will I have to set up ‘international roaming’ beforehand? I would ask customer services but I suspect they’ll tell me to do the most expensive option! Thanks a lot to anyone who can help! RichYPE (talk) 16:55, 15 March 2013 (UTC)

For the record, this is the SIM I am considering buying http://www.0044.co.uk/new-zealand/sim-card.htm

Once again thanks to anyone who can help! RichYPE (talk) 17:17, 15 March 2013 (UTC)

You seem to be getting mixed up. 'Roaming' is what happens when you take your UK SIM abroad with you. If you are using an NZ SIM you will be treated as a domestic NZ user, and charged whatever price the network whose SIM you are using decide. There would be no roaming involved.

Whilst the SIM you linked to should work fine, it seems a tad expensive at £19.99 with only $1 credit - a $20 NZ SIM would give you $20 credit. Personally, I would suggest waiting until you are in New Zealand and buying a $20 prepay (pay-as-you-go) SIM there, although you might want to research beforehand which plan is best for you, especially if you are planning on making calls back to the UK. A very brief Google search showed me three operators you might want to check out: Vodafone, 2degrees and TelecomNZ.

However, DO make sure your phone is unlocked first, otherwise you won't be able to use any SIM other than your current one. Best thing to do is find a friend (in the UK) on another network and borrow their SIM. If you can make a call using it, your phone is unlocked. If you can't, take it down to one of those dodgy so-and-sos on the market and get it done for a tenner. - Cucumber Mike (talk) 18:26, 15 March 2013 (UTC)

How long will you be visiting NZ ? One option is to bring your cell phone with you, but don't use it there, except for looking up phone numbers, etc. Instead, buy a local, basic prepaid cell phone when you arrive, and use that during your stay. I can't say what those cost in NZ, but here in Detroit that would cost about US$20 for 30 days/180 minutes. That sounds a lot easier and less risky than messing with SIM cards, to me. StuRat (talk) 08:43, 16 March 2013 (UTC)

I think you overstate the 'risk' and 'difficulty' of 'messing' around with SIM cards unless you're ultra incompetent or have some very weird phone. Even with the nano SIMs, you have to be very careless to damage the SIM card. In any case, shops specialising in phones also normally sell SIMs and often help you change the SIM if you ask, even if you didn't buy the phone from them. So the only likely risk if the OP screws up and thinks their phone is unlocked and it's not. But that's not really a risk here since the OP could likely either get the phone unlocked in NZ or buy a phone in NZ if they find out it's a problem. Since the OP will have to bring the SIM card with them (but most people do that anyway so they have access when they arrive back in the airport their home country), there is some small risk of loss of the SIM card if the OP is careless, but then again there's also risk of loss of either phone if they bring two phones (and juggling two phones will likely increase the risk over one). The SIM card is a lot smaller then a phone which means in some ways it's easier to lose but in some ways it's hard. In particular the small size, combined with the fact once they take it out they won't need it until leaving again, they should be able to stick it somewhere safe (compared to a second phone they want to have regular access). The only other real 'risk' is what happens when inside the phone when they change SIM. If contacts or SMSes are stored on the SIM, these will not be available, but will not be lost (and with most phones it's trivial to copy contacts from SIM to phone). SMSes may be more tricky but most modern phones even cheap ones store them on the phone, unless perhaps they run of storage and the SIM card can generally only store 20 or so SMSes anyway. Some smart phones may loss stored accounts if you change the SIM, so you will have to reenter passwords, possibly even if you don't do anything and change back, but if you've forgotten your passwords you likely have bigger problems anyway. If the OP wants to stay in reasonably regular contact with a whole bunch of people from the UK by SMS, having to mess around with two phones for contacts is probably not going to be easier and in particular, if the OP has a smart phone they may find a cheap phone extremely limiting, in terms of functionality, SMSing, etc. Note in particular if the OP wants to use data while here, while data prices are high compared to many other countries, wifi availability is even worse. Even in Auckland, it can be quite hard to find free wifi (coffee shops and other places, when they have it, often use commercial services and don't always even offer free access to customers). Hotels in particular often charge even for guests and for many places which charge, their prices often make mobile data attractive. (McDonalds is probably the largest free wifi provider here.) So if they do want to use the internet from somewhere other then a friend/relative's house and have a smart phone, either using the smart phone or wifi/USB tethering if it's supported by their phone (or using a 3G USB or similar device) would likely be a smarter idea then trying to rely on wifi. P.S. The cheapest phone here is probably around NZD20-30 with the SIM card being extra as mentioned in Cucumber Mike's post. Nil Einne (talk) 18:10, 17 March 2013 (UTC)

When it comes to picking the right locally bought SIM card to put in your unlocked phone, many companies can provide a special "international pre-pay" SIM card with preferential rates to some countries. When in Europe, I get good rates back to the UK from my locally bought international pre-pay SIM, as well as good rates to in-country numbers as well, much cheaper then the roaming fees if I stuck with my UK SIM card. Do some research on phone tarrifs before you go, then seek out their shop when you arrive - they'll probably have a shop at the airport. Astronaut (talk) 18:05, 21 March 2013 (UTC)

Are there ways to make my browser automatically redirect a page?

For example, every time I go on the wikipedia.org page, make my browser automatically redirect to en.wikipedia.org. (I know I can just type 'en.' instead, but this is just an example). Kinkreet^{~♥moshi moshi♥~} 18:11, 15 March 2013 (UTC)

What browser are you using? You can set up a keyword in Firefox, for example. So if you want to go to yahoo.com, you would set up a keyword for a bookmark of the Yahoo home page. The keyword would simply be yahoo and you wouldn't have to type the .com part. Or, using your example, you could use www.wikipedia.org as the keyword and it would go to en. This depends on you setting up several keywords for each bookmark though. Dismas|^(talk) 18:47, 15 March 2013 (UTC)

Is it possible to record TV with the Elgato Game Capture HD device?

This device is usually used for recording Xbox 360 or PlayStation 3 gameplay, but I was wondering if I could use it to record HD television. Nicholasprado (talk) 18:32, 15 March 2013 (UTC)

Without finding a reference I can't say for definite, but I'm going for an almost-certain 'No, you can't use it to record HD television'. The box has an HDMI input, but cannot decrypt HDCP - thus it can take the input from an XBox, but not from a cable decoder or similar. It apparently also has an S-Video port, so if you have a decoder with such an output, you could use that, but it won't be HD. If you only have HDMI-out on your device, but would like to use the S-Video port, you can get an HDMI S-Video converter, but they are expensive and you still won't get an HD signal. - Cucumber Mike (talk) 18:38, 15 March 2013 (UTC)

Having said that, I just found this. So, if you can find something to do the decoding for you (an Apple TV in this case) then you can do what you're asking. - Cucumber Mike (talk) 18:40, 15 March 2013 (UTC)

Smartphone app notifications

If you log out of an app like facebook on a smartphone, will it still give you alerts and notifications like if you leave it logged in? Clover345 (talk) 19:22, 15 March 2013 (UTC)

Mine doesn't (Samsung Galaxy Y GT-S5360). It might depend on your phone, phone's OS, or the settings of the app itself. KägeTorä - (影虎) (TALK) 12:35, 17 March 2013 (UTC)

Displaying only a specific string in a NET VIEW

In an attempt to view the list of printers from a server I remember one of my colleagues using NET VIEW and a specific command that only listed that strings he asked for. The command was something like " net view \\(server) find:"##" ", but now when I try it, it doesn't work. Unfortunately, said colleague is not present thus I can't ask him. Can anyone help? -- 143.85.199.242 (talk) 22:39, 15 March 2013 (UTC)

You were almost there - if you put a pipe character between the net command, and the find command like this:

net view \\computername | find "string to search for"

you may also wish to add a " /i" after the "find" to make the search case-insensitive. Cheers, davidprior ^t/_c 22:49, 15 March 2013 (UTC)

It worked! Thank you so much! -- 143.85.199.242 (talk) 22:57, 15 March 2013 (UTC)

March 16

USB2 drive faster on USB3 port

I've tested writing to a USB2 external hard drive while connected to a USB2 port and a USB3 port. It is about 16% faster on a USB3 port. Why is that? Bubba73 ^{You talkin' to me?}

That's an interesting observation. What are you using for the benchmark? A significant difference between the USB2 and USB3 protocols is that the latter has a lot more pipes and slots; they're briefly described in this document. Obviously with a USB2 drive, that alone doesn't help, as the host controller has to fall back on the USB2 protocol. But it does mean that the driver can use more space (essentially more and/or longer queues) within the host controller itself; it may be that this is allowing it to use smart features like Native Command Queuing better, giving a higher effective throughput. A second, perhaps more prosaic, possibility is simply that the driver for the USB2 path is older and rather conservative, and in writing the USB3 driver (where they had to rewrite that pipe and slot stuff anyway) they did a smarter, more aggressive, job of scheduling the IO, producing the more efficient use you're seeing. -- Finlay McWalterჷTalk 02:55, 16 March 2013 (UTC)

I wrote a program to test all of my drives. It writes 1MB blocks to a file repeatedly, for 15 seconds, then calculates the rate. Just out of curiosity, I switched the USB2 external HD to a USB3 port, and it was faster. I've switched back and forth and run it several times, and it is consistently about 16% faster when plugged into the USB3 port, compared to USB2. Bubba73 ^{You talkin' to me?} 04:18, 16 March 2013 (UTC)

You're may be better off with a longer time (so much more data); particularly if the drives are configured for write-behind then you risk the results of the benchmark being confused by different caching behaviour throughout the USB3 stack. Ideally you wouldn't be writing to files either (in case the file system too has some confounding effect), but to the physical disk surface instead. That's trivial on Linux and BSD (and I guess on OS-X), and possible (but increasingly difficult) on Windows (note that this will destroy partitions and data on that disk). -- Finlay McWalterჷTalk 04:33, 16 March 2013 (UTC)

It's not much different on Windows than on Linux. paths like \\?\Device\HarddiskVolume1 are the equivalent of /dev/hda1, and you can pass them to dd for Windows. Obviously you should be really careful if you do this on any OS. The "increasingly difficult" article seems to be about a mechanism to prevent writing to a disk region that's also mounted as a filesystem, which seems like a good idea to me. You should unmount any filesystems before clobbering them (by removing the drive letter in Disk Manager). -- BenRG (talk) 05:27, 16 March 2013 (UTC)

What would the question mark in \\?\Device\HarddiskVolume1 typically need to be substituted with? --NorwegianBlue ^talk 09:51, 16 March 2013 (UTC)

Nothing, the ? is a literal in this syntax. See Path_(computing)#Uniform_Naming_Convention or [3].Kram (talk) 19:46, 16 March 2013 (UTC)

I checked my program for errors and found none. I reran it, testing for 300 seconds on each of USB2 and USB3. On USB3 it was 16.8% faster. Then I thought that maybe I should test the same size of file, so I did 1000MB, and USB3 was 16.0% faster. Bubba73 ^{You talkin' to me?} 16:18, 16 March 2013 (UTC)

This implies that your file I/O bottleneck is not the speed limitation of the USB2.0 protocol, but is in fact an implementation-specific speed limitation somewhere else in your system. To prove this, calculate your data transfer speed, and determine if your USB drive is meeting the theoretical maximum data transfer speed for USB2.0 - 480 Mbits/sec. If you are not hitting this peak - why not? We can enumerate hundreds of reasons, ranging from software to hardware to signal-integrity problems. But it will all be speculation unless you can prove and isolate the root-cause for your drive operating below peak speed. Next, measure your USB2.0 drive connected to the USB3.0 port. Is it performing at the peak theoretical USB2.0 specification, or is it mysteriously outperforming its specification by operating in a non-standard way? We can enumerate hundreds more reasons that could be responsible, from vendor-specific protocol extensions to mislabeled marketing-ese. Prove this by collecting data using a USB protocol analyzer. Colleagues recommend the Beagle USB analyzer because it is cheap and easy, although I have no experience with it. If you have a large budget for this investigation, I recommend the USB analysis suite for your LeCroy scope. (It can also analyze USB3.0).

From what we currently have, all we can say is that your USB3.0 port can yield higher performance - even at USB2.0 speeds - than your USB2.0 port. Your system may use a higher-performance software- or hardware- path to your USB3.0 port, even when it is communicating using the USB2.0 protocol. Nimur (talk) 18:12, 16 March 2013 (UTC)

Are you using other USB devices on the same machine? My understanding is that frequently when there are multiple USB ports on a computer you effectively have the equivalent of a USB hub in your computer. So while you may have 5+ ports on the machine, they're all multiplexed into a single connection, so you don't actually get 5+ times the bandwidth. If you have other devices active, you'll never get the full USB2.0 data transfer rate, because the have to share. On the other hand, a USB3.0 system will by necessity have a higher bandwidth connection to the processor, so you'll be able to max out the 2.0 protocol bandwidth while still having room for the other devices attached to the computer, even if they're all USB2.0 -- 71.35.100.68 (talk) 19:20, 16 March 2013 (UTC)

Yes, I have several other USB devices in use (a thumb drive, a mouse, a printer, a scanner, and a connection to the UPS), mostly idle.

In one pair of tests, I got 26.0 MB/sec in USB2 and 31.5+ with USB3, so neither is close to the maximum 60 MB/sec of USB2, assuming 8 bits/byte (some things are 10 bits/byte, which would be 48MB/sec). Bubba73 ^{You talkin' to me?} 21:12, 16 March 2013 (UTC)

Resolved

Bubba73 ^{You talkin' to me?} 01:56, 19 March 2013 (UTC)

Algorithms Hacking

I think Donald Knuth is the greatest living authority on Algorithms in this planet. I am curious to know that if the so called "Hackers" like Kevin Mitnick or Kevin Poulsen or others have greater knowledge than Donald Knuth. And if advanced Computer Science and Algorithms are necessary to be a security expert like Kevin Mitnick or Julian Assange. Solomon7968 (talk) 15:05, 16 March 2013 (UTC)

Both Assange and Mitnick used subterfuge, primarily; they did not design algorithms to circumvent computer-security systems. I don't recall any interviews where either person specifically mentioned Knuth, but they both have espoused free software and its associated culture in numerous interviews. Nimur (talk) 15:31, 16 March 2013 (UTC)

This [4] reliable source implies third best ;-) Dmcq (talk) 19:22, 16 March 2013 (UTC)

Well, if we're going for esoteric humor, here's a link to my nitpick of Knuth's font nitpick. I still think it's bad form to nitpick a font glyph and then use a crudely-antialiased, badly palettized GIF as your example of "how to do it correctly." I mean, truthfully, seriously, has the man ...never heard of vector graphics? That web-page has baffled me for almost a decade and still has not been fixed. I honestly have come to believe that he leaves that webpage in its current form as a shiboleth to TeX hackers everywhere: always remember, your final output will be rasterized badly by somebody incompetent... no matter how hard you try to preserve the pristinely vectorized fonts, no matter what you do. Nimur (talk) 22:53, 16 March 2013 (UTC)

The difference between algorithms and hacking into systems is like the difference between architecture and burglary. I don't think there's much overlap in the skill sets. It's also weird to call hackers "security experts". Are burglars security experts? I suppose some are, but they don't have to be, and it's not the first group of people that comes to mind when I hear "security expert".

Kevin Mitnick now works as a security consultant so I suppose he is a security expert, but he's not famous for his consulting work. I don't think Julian Assange can be classified as a security expert. Both of these guys just are/were in the newspapers a lot; that doesn't make them experts on anything. -- BenRG (talk) 03:19, 17 March 2013 (UTC)

We've articles on both the older meaning Hacker (programmer subculture) and the current idea of Hacker (computer security). Um I see there is also a third article Hacker (term). I think there has been a bit of a WP:POVSPLIT here. Oh dear also Hacker (hobbyist). Dmcq (talk) 12:02, 17 March 2013 (UTC)

My speestream is diconnecting alot, what can be the problem?

My speestream internet modem (some example pic of the modem I found: http://www.weeta.net/reseau/free-adsl-efficient-networks-speedstream-5200/images/speedstream-5200-1024-01.jpg) is diconnecting alot, what can be the problem? Right now he is disconnecting almost every 2 minutes, but some days it take 1.5 hours to disconnect.201.78.129.104 (talk) 16:41, 16 March 2013 (UTC)

The problem probably could be anywhere - in the modem, in the lines to your ISP, or on their end. In the past, my cable modem behaved like that, and the problem turned out to be in the lines between me and them. Bubba73 ^{You talkin' to me?} 02:22, 17 March 2013 (UTC)

March 17

power consmuption

Which is the power consumption of the ati fire gl v7300??

Iskánder Vigoa Pérez (talk) 01:56, 17 March 2013 (UTC)

Its datasheet recommends a 450 watt power supply for the entire system. The actual GPU and CPU power consumption varies at run-time based on workload: here's a white-paper, AMD PowerTune. It seems reasonable to expect the card's total power to exceed 100 watts during heavy use. Nimur (talk) 02:38, 17 March 2013 (UTC)

thanks!! could be any situation, or any tiny chance, in which this card colud be a better choice than a quadro 2000???

Iskánder Vigoa Pérez (talk) 03:29, 17 March 2013 (UTC)

Short answer: no. The FireGL7300 has fewer features and lower performance - even if you're referring specifically to the Quadro 2000 and not the current Quadro K2000, with Nvidia's new Kepler architecture.

FireGL7300 is older technology, has fewer hardware capabilities overall, contains support for older revisions of common APIs like OpenGL and DirectX, does not appear to support any GPGPU APIs, and has lower performance across the board. It would at least be a fair comparison if you compared one of the FirePro series to the Quadro 2000.

I took a cursory look at each company's current product lineup, and I would say that AMD/ATI's closest match for Nvidia's current Quadro K2000 is the FirePro W7000. There is not an easy apples-to-apples comparison, but these two products have a large number of specs in the same ballpark.

Now, whether those features are something you need will affect whether any card is "better." If you do not need a GPGPU processing engine, then there is no sense paying a premium for it. And you asked if there is any situation where one could prefer the 7300...well, there are a lot of scenarios...!

I am of course partial to CUDA, so I lean towards Nvidia's products, but I can admit that this is vendor lock-in; I am unwilling to convert my old CUDA code to OpenCL, so I have never performed an actual, fair benchmark comparison on my own code. Many friends and colleagues highly recommend OpenCL, and because it is implemented as free software, I can see much merit in that platform. ATI has strongly embraced OpenCL, while Nvidia's support for it is always secondary to CUDA.

Many friends and colleagues profess a bias towards ATI or Nvidia, because of the belief that they one company produces more stable graphics drivers (though I have no data to confirm or refute these claims). Any of these can be construed to make the FireGL7300 a "better" card, despite any technical shortcoming. I still operate a GeForce 5800 on one machine, and it is a "better" card than any other available today, despite its archaic performance metrics -because it was the last Nvidia card that used the AGP interface, and I refuse to let one of my perfectly functioning machines succomb to the garbage bin. Nimur (talk) 04:27, 17 March 2013 (UTC)

Thanks again, I was thinking something like that already, just wanted to be sure… my current cards are Quadro 2000 (without the k) and, at least for now, I’m not interested in move on to the newer ones, but I have this chance of get a “almost non used” firegl v7300 and almost for no cost, and was going in one of two directions, 1 : resell it or give it to some friend or something or 2: get rid of one of my “heavy used” quadro and put the GL instead… but I gest it’ll be the first one

but any way… it would be very helpful a more precise power consumption… thanks for you r comprehensive answer

Iskánder Vigoa Pérez (talk) 23:43, 17 March 2013 (UTC)

Moving a large number of files

My second internal drive has about 380GB in about 320,00 files that I want to move to an external USB 3 drive so I can reformat the internal drive and copy the files back. The external drive is fast enough, but there is a lot of overhead in creating all of those files. A straight copy in Windows says that it will take more than 1 day. Is there a more practical way to do it? Bubba73 ^{You talkin' to me?} 04:31, 17 March 2013 (UTC)

Let me back up to the reason I want to do this - there should be a better solution. This is the second internal HD and I want to remove the Windows, Program Files, and Program Data folders. If I try to remove them, for many of the files it says that I need the permission of TrustedInstaller to delete them. Is there a way for me to get permission from TrustedInstaller? (I don't know what that is.) Bubba73 ^{You talkin' to me?} 04:47, 17 March 2013 (UTC)

I've found that using the command line copy/move commands are lot faster than using the GUI to copy the files. You could try that. RudolfRed (talk) 04:48, 17 March 2013 (UTC)

I've just found this which should tell me how to do the second thing. Bubba73 ^{You talkin' to me?} 04:50, 17 March 2013 (UTC)

Well, my Windows 8 system is different. It says to right-click on the folder, properties/security/advanced button/owner tab, but there is no owner tab. Bubba73 ^{You talkin' to me?} 05:07, 17 March 2013 (UTC)

It sounds like you want to create a full disk image. On Windows, you will need to use a separate program for that task (it is not built in to Windows). Many free and commercial options are available: we have a comparison of many tools. Nimur (talk) 04:53, 17 March 2013 (UTC)

Actually I don't want to do that - I actually want to get rid of the Windows, Program files, and program data folders that are on my second internal hard drive. And it won't let me because I need permission of TrustedInstaller (the owner). Bubba73 ^{You talkin' to me?} 05:07, 17 March 2013 (UTC)

If I'm understanding this correctly, you want to grab a bunch of files (which is just a selection of files and not everything on the drive), move them to an external drive, and then format the original drive which would wipe it. Then move those files back. This would leave the internal drive with just those files and no remnants of the OS. Right? Dismas|^(talk) 05:12, 17 March 2013 (UTC)

Right, and I can't delete them directly because they are owned by TrustedInstaller. I tried two sets of instructions about how to do that, but they don't match what is on my computer. Bubba73 ^{You talkin' to me?} 13:43, 17 March 2013 (UTC)

And in case you are wondering how it got that way, when I added the second internal HD I mirrored the C drive to it. The idea is that if the C drive failed, I could just swap and be back up. Well, since then I've installed Windows 8 and most of the programs have been updated, so the system stuff on the second internal HD is way out of date and will never be used. Bubba73 ^{You talkin' to me?} 17:53, 17 March 2013 (UTC)

Windows' estimates about how long things will take aren't very reliable. I don't know of a better way than using rsync or Robocopy. -- Finlay McWalterჷTalk 11:49, 17 March 2013 (UTC)

I started it and after a while it got 1% done, so it may not be accurate, but it was going to take a long time. Bubba73 ^{You talkin' to me?} 13:43, 17 March 2013 (UTC)

I don't really get why you can't take ownership, presuming you're using an administrator account. I'm using Windows 8 right now and taking ownership is right there. Click on the security tab, click on the advanced button (which says it's for 'special permissions or advanced settings' so is kind of a give away) and it should list owner. Right next to the owner there should be a 'change' you can click on. This has changed slightly since Windows 7 (and previous versions) but it's one of those things which has changed so little that it's easy to find (compared to some other things). There are of course other ways to take ownership. Nil Einne (talk) 18:17, 17 March 2013 (UTC)

But after clicking on that "change", I don't see anywhere to change it. It has buttons "object types", "locations" and "check names" and a field "enter the object name to select", but I don't see how to change the owner. Bubba73 ^{You talkin' to me?} 18:22, 17 March 2013 (UTC)

For the copying, you could use a program like 7-Zip to compress the files onto the new hard drive (maybe with zero compression - the point is that this would only write one file and hence be much faster than copying them one by one. I have always been annoyed about how slow this is in Windows and I am amazed to hear that they have not yet fixed it). You could also safely delete all "temporary internet files" before copying; that directory (at least on older Windows versions) tends to hold a vast amout of very small files that it takes an eternity to copy. Jørgen (talk) 20:47, 17 March 2013 (UTC)

I've just been testing my various drives for the speed of opening and closing files in Windows, and I have some unusual results. I'm double-checking them before I ask about them here, but some drives take on the order of 0.1 second overhead whereas others are on the order of 0.001 seconds. Bubba73 ^{You talkin' to me?} 01:49, 18 March 2013 (UTC)

Resolved

Changing the USB drives from "quick removal" to "better performance" made the difference. Bubba73 ^{You talkin' to me?} 02:00, 19 March 2013 (UTC)

And I got the process done in a reasonable amount of time and recovered over 200GB of HD space. Bubba73 ^{You talkin' to me?} 05:03, 19 March 2013 (UTC)

Book recommendation request

I could go wandering from article to article on Wikipedia and get very lost and very confused in no time, so I'm looking for a book recommendation or primer on cyber security, hacking, what part algorithms play, etc. I'm attending computer engineering classes right now and am in my first year or so (part time so it's hard to say), so I don't need the "Dick and Jane" version of things. Is there anything like this out there? Maybe a text book that I can pick up for cheap? Dismas|^(talk) 04:45, 17 March 2013 (UTC)

You might find that The Code Book meets some of your needs.--Phil Holmes (talk) 11:43, 17 March 2013 (UTC)

Bruce Schneier's Applied Cryptography or Practical Cryptography, and Ross J. Anderson's Security Engineering. -- Finlay McWalterჷTalk 11:45, 17 March 2013 (UTC)

Applied Cryptography is the bible of cryptography reference texts. It explains everything, however it's big and pricey. I've read The Code Book and I remember liking it, but if I remember right it's more in the genre of nonfiction like Malcom Gladwell and not as much a reference text. I think Practical Cryptography is another good choice. If you want more than just cryptography or codes though, you might find a sensationally titled, but nevertheless good overview in Hacking Exposed 7 (there's a whole series, this is the most recent). I have an old used copy somewhere and I found it interesting.

Are there any specific areas you're interested in? I know of some online resources that are really good on specific, small topics, if there were a few of those you were interested in. I know some of our articles, math ones particularly, are not good introductions to a topic. Shadowjams (talk) 00:58, 18 March 2013 (UTC)

Thanks for all the responses!!

There are no specific areas, I guess. I don't think I have the aptitude in math to get a degree in cryptography but I'd like to know more about it. Like when groups hack in to Twitter or Sony or the local utility company. I'd like to know roughly how they did it. I don't necessarily want detailed specifics of how to do it, partially because I'm not sure that I'd understand them, but I'd like to know more than "Such-n-such was hacked and a million credit card numbers were stolen". Do they just start a PuTTY session and start trying passwords or what? Also, I'm often asked by friends various questions about how things work, and I'd like to be able to break it down for them. (One recent one was what IP addresses are)

And yes, our technical subject articles get very technical very quickly. Salt (cryptography) and Hash function were two that I tried to slog through last night. Thanks again, Dismas|^(talk) 01:55, 18 March 2013 (UTC)

Most security breaches have nothing to do with cryptography; they usually involve social engineering and/or exploits of the sort listed in Category:Computer security exploits and its subcategories. SQL injection is currently a common technique—I think that's how the PlayStation Network was hacked, though oddly the Wikipedia article doesn't say. There are attacks that involve nontrivial cryptanalysis, such as cracking of wireless networks and rainbow tables, but generally the people that do it don't know anything about cryptography—they use software written by someone else. -- BenRG (talk) 02:42, 18 March 2013 (UTC)

One more question, would picking up a copy of 2600 be a good idea? Dismas|^(talk) 01:55, 18 March 2013 (UTC)

It's a fun read sometimes, picking up a copy will give you some ideas about how systems work. Although articles in it are hit and miss. Sometimes people write articles about really basic methods (or they feel basic to me) but then sometimes I'll hear about some interesting tool or configuration, so there's that. A good primer on cryptography is important to know, not the math so much, but just how the primitives fit together and what you can and cannot expect. But as Ben says, cryptography isn't the weak link. The sophisticated attacks you hear about leverage some vulnerability and go from there. You should read any of the books or blogs about penetration testing. Shadowjams (talk) 15:20, 18 March 2013 (UTC)

How to tell if my graphics card supports OpenGL 2.1 and GLSL 120 ?

ATI Radeon Xpress 1100

Driver Date: 3/14/2007

Driver Version: 8.360.0.0

I tried to update the driver, and it said it was already up to date. There appear to be different versions of that card, not all of them support OpenGL 2.1 and GLSL 120. How can I tell, for sure ? StuRat (talk) 10:24, 17 March 2013 (UTC)

Is it the notebook or desktop one? And which OS? Shadowjams (talk) 01:03, 18 March 2013 (UTC)

Desktop (compact form), Windows 7. StuRat (talk) 01:33, 18 March 2013 (UTC)

Is this the driver? Shadowjams (talk) 01:55, 18 March 2013 (UTC)

Well, "ATI Radeon Xpress Series" was listed there, along with many other series, but I think I just have the default driver that came with the device. Would downloading that driver add OpenGL 2.1 and GLSL 120 support ? StuRat (talk) 02:44, 18 March 2013 (UTC)

Ah, here we are. Sorry for the delay, StuRat, I couldn't track this tool down: ATI GPU Services Library... the tool to determine at run-time whether your current hardware and software support a particular feature-set. Remember, OpenGL is an API, not a hardware specification. Technically, your system can "support" any revision of OpenGL at all, but if the hardware and low-level driver is unable to accelerate a particular feature, it is often better to design your application to avoid that feature. OpenGL itself has numerous methods to verify if an extension is present; start with the top-level documentation.

According to the programmer reference manual, your GPU is a member of a product series that supports ATI's DirectX 9 Vertex shader model 3, documented here. As with any shader program, you need to pay close attention to hardware and compiler limitations: just to remind you, the OpenGL Programming Guide from ATI: reminds you that shaders are programs that may or may not run with acceleration. "The driver will always report the word “software” in the info log if the shader forces the driver to not render fully hardware accelerated."

Finally, if you're asking about OpenGL 2.1 as a user rather than as a developer - the short answer is, sorry, your Xpress 1100 is a few years old and was never the top-of-the-product-line-up, even when it was new. It was marketed as an integrated GPU - a solid sort of work-horse, but not a high-performance or gaming processor. It may support OpenGL2.1 and DirectX9, if you have the most current drivers; but its performance will be low compared to most other GPUs. Nimur (talk) 04:19, 18 March 2013 (UTC)

Thanks. I need those capabilities as a developer. I'm taking an online edX Computer Graphics class, which uses Microsoft Visual Studio 2012 for Windows Desktop. It's giving me errors, and they suggested that those may be from a lack of support for OpenGL 2.1 and GLSL 120 in my graphics card/driver. So, it looks like I need to go buy a new card, right ? (I have another question on that, down below a few Q's.) StuRat (talk) 06:12, 18 March 2013 (UTC)

iPod Touch - Moving a File to a Folder

On the iPod Touch, how do I move a file to a folder? I have files which I have already transferred from my PC to my iPod (not music files, these are documents, because I use it for work). I also have lots of folders I have been able to make on the iPod itself. However, I am unable to find a way to actually organize my documents and put them all in the folders, so all I have is a bunch of empty folders and a disorganized mess of documents. If I can make folders, then there must be a way to move those documents into them. Can anyone help? KägeTorä - (影虎) (TALK) 11:30, 17 March 2013 (UTC)

March 18

Windows overhead time in creating and closing files

In my message above, I talked about how long it was taking to write files to an external HD, a seemingly large time per file. I did some tests on my computer, Windows 8, quad-core i7, 16GB RAM. None of the drives are compressed and only the C drive is indexed. THe G drive is dedicated to Carbonite Mirror Image, so there is something else accessing it. And the WD drive has to wake up if it has been idle for a while.

Drive C: internal HD

25 files of size 16777216    0.376 sec   0.01504 sec each
25 files of size  4194304    0.089 sec   0.00356 sec each
25 files of size  1048576    0.044 sec   0.00174 sec each
25 files of size   262144    0.023 sec   0.00092 sec each
25 files of size    65536    0.022 sec   0.00089 sec each
25 files of size    16384    0.020 sec   0.00081 sec each
25 files of size     4096    0.019 sec   0.00075 sec each

...

Drive I: Seagate 4TB USB3

25 files of size 16777216    7.277 sec   0.29107 sec each
25 files of size  4194304    3.995 sec   0.15980 sec each
25 files of size  1048576    2.924 sec   0.11697 sec each
25 files of size   262144    2.670 sec   0.10680 sec each
25 files of size    65536    2.559 sec   0.10234 sec each
25 files of size    16384    2.967 sec   0.11869 sec each
25 files of size     4096    2.690 sec   0.10759 sec each

Notice how large the minimum time is on the Seagate. I Tabulated the overhead, based on the time to write 4KB:

Drive C internal HD            0.0007 seconds overhead
Drive F WD 6TB USB3            0.0127 seconds overhead
Drive G Seagate 3TB USB3       0.3614 seconds overhead
Drive H 2nd internal HD        0.0008 seconds overhead
Drive I Seagate 4TB USB3       0.1076 seconds overhead
Drive L HP 1TB USB2            0.0128 seconds overhead

Notice how much overhead there is on the Seagates. But they are fast per MB when writing large files. Why would the time be so large on the Seagates? Bubba73 ^{You talkin' to me?} 02:30, 18 March 2013 (UTC)

And how do you get things like this to line up vertically, as they do in a text editor with fixed-width fonts? Bubba73 ^{You talkin' to me?} 02:37, 18 March 2013 (UTC)

You can use the <code> </code> tag:

WWW

III

Or just put a space in front, like so:

WWW
III

StuRat (talk) 02:48, 18 March 2013 (UTC)

Write-back caching may be disabled on the USB drive. Try the "option two" described here. (I fixed the text alignment.) -- BenRG (talk) 02:57, 18 March 2013 (UTC)

That was it!!

Drive C internal HD            0.0010 seconds overhead
Drive F WD 6TB USB3            0.0008 seconds overhead
Drive G Seagate 3TB USB3       0.0007 seconds overhead
Drive H 2nd internal HD        0.0008 seconds overhead
Drive I Seagate 4TB USB3       0.0008 seconds overhead
Drive L HP 1TB USB2            0.0007 seconds overhead

All of the external drives had "quick removal" selected instead of "better performance". The Seagates also had the Write Cache buffer flushing on, I turned them off. The other two externals didn't have that option.

When you are writing > 300,000 files, a 0.1 second overhead is a lot.

Resolved

Bubba73 ^{You talkin' to me?} 03:35, 18 March 2013 (UTC)

All of the drives are actually taking the longer times. But with write caching enabled and write cache buffer flushing disabled, Windows is telling you "it's done!" when the data is not actually on the drive yet. It does get flushed eventually (regardless of the option) but.. if you run external drives that way, make very certain that you go through the "request to remove" procedure before removing them. For the internals, be sure you do an orderly Windows shutdown, don't just power off. Otherwise you risk losing some of your writes. When they give you a choice between "optimize for performance" and "optimize for reliability", they're not kidding. Jeh (talk) 19:07, 18 March 2013 (UTC)

Resolved

And now copying the second internal drive to the external USB 3 drive (discussed above as "moving a large number of files") took less than 2 hours instead of the projected > 1 day. Bubba73 ^{You talkin' to me?} 01:59, 19 March 2013 (UTC)

Crucial.com equivalent that recommends graphics cards for my PC ?

I apparently need a new graphics card with OpenGL 2.1 and GLSL 120 support. I'd like to run a scanner like the one at Crucial.com, and have it recommend a range of graphics cards for me. But, Crucial.com apparently doesn't do graphics cards. Is there another web site which does ? StuRat (talk) 03:05, 18 March 2013 (UTC)

Every electronics site: Newegg, Amazon, the Best Buy's of the world. In your case you need to make sure 1) you have a slot that can take the card (PCI x16 I think is what most use these days but someone correct that if I'm wrong) and that you have enough space in your compact desktop, 2) that you have an extra 5V powerline coming out of your power supply. I would suggest getting a few candidates and search for benchmarks for them and compare that way to find the best price/performance tradeoff. Also, be leery of the model numbers; their performance is often not related to the series number and same series cards can vary wildly in performance. As for the standards, I assume any modern desktop card will have both, but check in case because it seems you need those. Shadowjams (talk) 09:19, 18 March 2013 (UTC)

I'm trying to avoid having to dissect my computer before I get the new graphics card, to find out all that info. That's why I was hoping for software which can just scan the computer to figure all that out. Otherwise, I either am without the computer until I get the new card, or I have to jam it back together with the old card, just to dissect it again when I get the replacement card. StuRat (talk) 04:42, 19 March 2013 (UTC)

speaking from experience, definitely pay attention to the requirements of the card regarding the capacity of the power supply (in addition to the dedicated extra graphics card power cable). in my case (pretty bottom of the barrel by current standards, doesn't have the extra power cable) like a 10% shortage in the power supply rating meant the replacement card would not run at all, the next step down card which was speced for total power which the PS could deliver runs fine. Why I consider this odd/interesting, is that I assume the rest of the PC must vary in how much power it consumes, therefore for a given rated power supply, I would have assumed that given a particular power supply, the amount of spare power left over for the graphics board would vary from one pc to another, but ?? Gzuckier (talk) 15:58, 18 March 2013 (UTC)

UPDATE: OK, I give up on finding a scanner to do this, but, on what web site can I do the following:

1) Give it my computer model (Dell Optiplex 320 DT, compact form).

2) Give it my requirements (such as OpenGL 2.1 and GLSL 120 support, and power supply wattage and RAM limitations).

3) Get a list of matching graphics cards.

4) Compare each on price and features.

Dell's site does 1 and 3 only. Best Buy does 3 and 4 only. StuRat (talk) 19:17, 19 March 2013 (UTC)

Hard drive failed?

I just bought a new desktop to replace a 2006 laptop. I also have a Dell Dimension 8200 from 2003, that has been sitting under my desk not being used for years. Since my new desktop will be located under my desk as well, I want to remove the 8200 and put it into storage, but before putting it away I wanted to do a total backup (just in case there was anything of importance that I didn't put on my laptop in 2006). I began the backup, which proceeded fine for about 30 minutes, until the hard drive began clicking (a sort-of click of death, in groups of four, a pause, then four, pause, etc) and everything completely froze. During my many cycling attempts, sometimes it will boot into XP extremely slowly, and sometimes it will fail to boot the OS at all. Just to be sure, I took the hard drive out, cleared it of dust, then reconnected it, to no avail. Is there any hope for recovery? -- Tohler (talk) 03:09, 18 March 2013 (UTC)

If you copied over anything you thought worthwhile in 2006 and haven't wanted stuff since there is no need to bother with anything on that old computer. Its only purpose in the world now is to frustrate you and waste your time. I would suggest you carefully remove the drive from he old computer, put it on a spare concrete block or thick piece of wood on the ground, and then hit it viciously with a sledge hammer. That will stop you worrying about recovering anything from it and make you feel much better. Dmcq (talk) 08:20, 18 March 2013 (UTC)

Someone believes I should help you waste your time so in that case you can probably put the old disk into the new machine and then run a disk checker or even a professional package on it. This will avoid needing to boot from the disk and the disk may still click a lot before the checker finishes but it probably won't crash the machine. I'd put the disk on iits side too and tap it lightly while off in case some flake or dust has come free. Plus it may work better if left for a little while to warm up a bit inside the new desktop. Also with it in the new desktop you can look at some directories even if there are problems elsewhere. The new drive may cause the line it is on to run slow so take the disk out when you've finished with it. Then when you find there really isn't anything worth the bother there you can crush it. Dmcq (talk) 15:36, 18 March 2013 (UTC)

Thanks for your reply. I already attempted to get all the dust possible off, with no success. I will try with the new desktop later. Thank you for your humorous first comment, it made me laugh :) -- Tohler (talk) 17:43, 19 March 2013 (UTC)

SAMSUNG T10 MP3 PLAYER

where can I find the software (driver) for Samsung T10 MP3 Player? Thank you.175.157.1.97 (talk) 08:49, 18 March 2013 (UTC)

Quick - to the Google! First hit is Samsungs product page - seems like good place to start. WegianWarrior (talk) 09:14, 18 March 2013 (UTC)

March 19

Pipe command-line output to Python instead of Perl

If I got something like

find -type f -name "*.txt" -print0 | perl -nle ...

can I pipe the output to Python instead of Perl? How would Python deal with the list it's getting? OsmanRF34 (talk) 00:39, 19 March 2013 (UTC)

Yes, and you would receive the input from the "sys.stdin" file-like object. The easiest way to deal with the input would probably be to slurp the entire input into a string, and then split it on the null characters. e.g. sys.stdin.read().split('\0'). That will give you a list of the entries (as well as a final empty string). As far as I know, there isn't a generator version of split (one that will yield entries as they come in, rather than all at once after the find command has exited), though you can write a simple one (See [5] for examples). - Note that in most cases, unlike perl, a python one-liner probably isn't going to work for you, so you'll probably have to write a small script to a file before you can use it in a pipe. -- 205.175.124.30 (talk) 03:03, 19 March 2013 (UTC)

And what makes Python less appropriate for one-liners than Perl? OsmanRF34 (talk) 13:58, 19 March 2013 (UTC)

If nothing else, the rule that only one colon may appear on a Python line. The off-side rule would also be confusing, at least. You can, however, write multi-line "one-liners" with one of a few tricks:

$ python -c "if 1:
>   print 2"  # or single quotes
$ python <<EOF
> if 1:
>   print 2
> EOF
$ python -c $'if 1:\n  print 2'
$ nl=$'\n'; python -c "if 1:${nl}  print 2"

(Only the last two are literally single lines, of course.) These are written for bash (shell); most can be modified to work with tcsh. --Tardis (talk) 14:47, 19 March 2013 (UTC)

While the syntactic use of newlines and indentation would likely be the primary technical limitation, there's a social component that also shouldn't be overlooked. Piping input to a command line one-liner is one of the core use cases of Perl. There are websites out there dedicated to collecting and indexing useful Perl one-liners. If a Python site talks about a one-liner, it's usually regarded as a linguistic curiosity or the use of an esoteric language feature. Additionally, if you ask a group of helpful Perlites for help in transforming your program into a one-liner, they'll likely try to one-up each other for the shortest/most elegant/most "one-liney" version of the program. In contrast, a group of helpful Pythonistas would probably question why you need a one-liner in the first place. It's not just getting help with one liners - the culture also influences language development. If you went to the Perl maintainers with the argument "if you added this new feature, it would make writing one-liners easier for these use cases", they'd probably seriously consider your proposal (in part because of TIMTOWTDI). If you did the same to the Python maintainers, they'd (perhaps vehemently) disagree that one-liners are a use case that deserves consideration in language design, demanding other rationales for adding things to the language (c.f. The Zen of Python). As such, Perl has more features that are helpful for one-liner writing than Python does. -- 205.175.124.30 (talk) 21:13, 19 March 2013 (UTC)

How do I contact someone on Wikidoc

This question is duplicated from the humanities desk, where I have answered it. Looie496 (talk) 01:48, 19 March 2013 (UTC)
The following discussion has been closed. Please do not modify it.
My problem is I need to ask a question. To a person who edited on wikidoc. She did not state her source of information. she does not have a talk page. I can not get a wikidoc account. Because I am not a college student in med school. I cant edit either. So how would i be able to contact is there a way. I need to ask her a question. Because I cant find the source of her statement. — Preceding unsigned comment added by 209.174.186.167 (talk) 01:07, 19 March 2013 (UTC)

IP Address

I have just done a geolocate on an IP address on a question on the Lingo desk, and the website I use first tells me my own, before I can input the one I am asking about. Today, it said my IP geolocated to Poland. I am in the UK. Why would this happen? I am not using a proxy. KägeTorä - (影虎) (TALK) 02:42, 19 March 2013 (UTC)

Does the site correctly identify your ISP? - Cucumber Mike (talk) 10:11, 19 March 2013 (UTC)

Strange. It only happens when I am using the Opera browser. It must be something in the browser itself, then - maybe the Turbo settings or something. Firefox correctly says UK. KägeTorä - (影虎) (TALK) 11:58, 19 March 2013 (UTC)

Yup, you've got it. Turbo mode uses Opera's servers to pre cache sites - effectively they suck the data in at high speed at their data centre and compress them, then you download the sites from them. The sites therefore see your location as that of Opera's servers. I'm not sure if this happens for all sites, or just frequently visited ones. Funnily enough I haven't been able to find confirmation of the effect on IP geolocation from Opera themselves, but there is plenty of anecdotal evidence out there on 'tinterweb. - Cucumber Mike (talk) 15:05, 19 March 2013 (UTC)

Is it possible to create a n-body pertubation simulation app with the Blender (software)?

I want to allow the user to enter input data from the keyboard and to copy data from clipboard. 1.55.38.245 (talk) 09:33, 19 March 2013 (UTC)

Anything is possible... Blender is scriptable in Python. You can even create custom GUIs. Is it the best way to implement an n-body simulation? Probably not; you're cornering yourself into limiting the simulation accuracy and performance by explicitly tying the simulation to its 3-D animation. But, you know your application needs better than anyone else. Nimur (talk) 11:47, 19 March 2013 (UTC)

Also, you may like VPython better than Blender, if you're aiming for simplicity in physics simulation and animation. Nimur (talk) 12:01, 19 March 2013 (UTC)

Problems compiling

Hi all, I'm hoping for some general advice on pesky compiles, and specifically some how-to on hunting the bugs. I am attempting to compile software written in C and Fortran, using gcc and gfortran on a Mac. The software has several dependencies, including Hierarchical Data Format (4 and 5), and Message_Passing_Interface, which I believe are all installed correctly. Anyway, when I ./install.sh, I get errors like "Can't find file: mpif.h" and "make[1]: *** No rule to make target `rconstants.mod', needed by `consts_coms.o'. Stop. make: *** [all] Error 2"

So, I conclude that I haven't properly setup my makefiles to point the the correct directories for includes, headers etc. My main question: how can I find *where* it was looking for e.g. mpif.h? How do I determine which makefile and line # was being processed when the error was given? This kind of info should theoretically help me track down and fix the problem, right? I am somewhat Unix conversant, but don't usually do much compiling (outside of Macports, which always works fine). Any specific or general advice is welcome. Thanks in advance! SemanticMantis (talk) 14:45, 19 March 2013 (UTC)

The makefile should pass lists of include file directories to gcc with the -I dir directive; you may need to first look at the trace of the compile run to determine that, and then find the corresponding rule in the makefile. In some cases these will be direct (from makefile variables) and in other cases they may result from the output of a program like pkg-config. GNUmake has a -d option to get it to show it's workings, but it's usually not very helpful. -- Finlay McWalterჷTalk 15:28, 19 March 2013 (UTC)

If all else fails, you can do debugging by putting a print between every line. The bug which stops the compiler should occur between the last line to print and the first line not to. If there are just too many places to put prints, you can do it in steps. For example, in a 1000 line file, you could put in 10, evenly spaced ("Trace 1" - "Trace 10"). Try to compile, and that will get you to a 100 line chunk where it fails. Then add 10 prints there, evenly spaced, to get it down to 10 lines (say "Trace 3.1" - "Trace "3.10"). Finally, add prints on every line in that 10 line chunk (say, "Trace 3.4.1" - "Trace 3.4.10").

If all else fails, you can do debugging by putting a print between every line. The bug which stops the compiler should occur between the last line to print and the first line not to. If there are just too many places to put prints, you can do it in steps. For example, in a 1000 line file, you could put in 10, evenly spaced ("Trace 1" - "Trace 10"). Try to compile, and that will get you to a 100 line chunk where it fails. Then add 10 prints there, evenly spaced, to get it down to 10 lines (say "Trace 3.1" - "Trace "3.10"). Finally, add prints on every line in that 10 line chunk (say, "Trace 3.4.1" - "Trace 3.4.10").

A few things to watch for doing this, though:

1) There are cases where, due to flushing of different buffers, the prints are not synchronized with the error messages. So, you could get:

 Trace 1.2.3
File not found
 Trace 1.2.4

But this doesn't necessarily mean the line between those two prints produced the error. However, if the compiler actually stops, then the last trace print should be a legit way to find the error.

2) The place where a bug manifestation occurs is not always the cause of the bug. For example, the "File not found" error could mean some previous command to define the search path failed.

3) Prints inside loops with many iterations can be excessive. Try to avoid putting prints in such places, unless you have determined the bug to be inside that loop. Even then, you might want to first set a counter, to determine how many runs of the loop succeed, and then only do prints after that number of runs of the loop. (If it fails after a variable number of runs of the loop, you're screwed. You'll just need to wade through the massive output file.) StuRat (talk) 15:36, 19 March 2013 (UTC)

Thanks, Finlay. First, can you clarify what you mean by "trace of the compile run"? Is it just the standard out stream of text, or something else? In this case, I know where mpif.h is (/usr/local/include), and the makefile has MPI_PATH=-I/usr/local/include/ -- but I still get "Can't find file: mpif.h" which is repeated about 20X. Does that mean it's looking in 20 places and failing all of them? I'm sure I'm betraying some ignorance here, but I do appreciate the help.

Stu, that's an interesting idea. But I'm not sure where you mean to put print statements. I don't think I'm even getting to any "real" compiling, just failing on dependencies (your second option). So, do you mean to put print statements within the makefiles? I really thought there would be a way to get it so spit out something like " mpif.h not found in foo-dir... mpif.h not found in bar-dir", etc., so that I can tell which paths and path variables it is working in. (In this case, I suspect it is looking for mpif.h in places other than what is declared by MPI_PATH=) SemanticMantis (talk) 15:53, 19 March 2013 (UTC)

Yes, I was talking about putting prints in the makefile. If it calls other makefiles, you can then add prints to those, once you determine which of those is the problem.

One things you can try for "file not found" errors is copying the file into the current directory, which is often included in any search path. StuRat (talk) 15:58, 19 March 2013 (UTC)

Problems connecting to the Internet with new computer

I have a brand new computer that I am unable to connect to the Internet with. It's not a hardware problem with the ethernet cable nor the modem itself, as I can use the cable on the laptop and have no problems. The modem is a "Surfboard Digital Voice Modem" (picture of it here), and my setup for all the hardware seems to be (Computer + Cat5) > modem > (component that splits, one line coming from the television, one from the modem) > wall jack. My ISP is Cox Communications, if it helps. Could my cable modem be blocking the second computer, and if so, how can I fix it? -- Tohler (talk) 18:16, 19 March 2013 (UTC)

Yes, it could be. Modems and routers sometimes do something called 'MAC filtering' - basically only allowing certain computers to connect; it's a little like a gate that only opens for cars with a certain registration. To check if that's the case, try this: connect the cable to your laptop, and then open a web browser on the laptop. Click here -> http://192.168.0.1 and, if a password is requested, enter username admin and password motorola. Do you get a configuration page? If so, have a hunt around in the menus for MAC filtering and turn it off. Now try connecting the new computer.

If you can't get to the configuration page, post back here and we'll try and think of something else. - Cucumber Mike (talk) 19:48, 19 March 2013 (UTC)

Scrub that, I've just had a thought. Try this: Unplug the Ethernet cable from your laptop. Switch off the modem (i.e. turn the power off) and wait 30 seconds. Now plug the Ethernet cable into your new computer and, finally, turn the modem back on. Any joy? - Cucumber Mike (talk) 20:01, 19 March 2013 (UTC)

• "I am unable to connect to the Internet" is a useless problem report. What specific action did you take, what result did you expect, and what result did you observe? In other words, what is the observation that tells you that you are failing to connect? (Also, what kind of computer is it and what OS is it running?) Looie496 (talk) 21:05, 19 March 2013 (UTC)

running two OSes in parallel

I know I can dual boot my harddrive so I can choose between running either, for example, linux or windows when I load up, and I can have dual screen and be doing two different things at once, but is there any way of combining these and running a different OS on each screen?

Kitutal (talk) 20:44, 19 March 2013 (UTC)

If you have a powerful enough computer you could run one OS in a Virtual machine. However it does need quite a lot of computing power (if you think about it, you'd effectively be running two computers on the same machine), so you might find it quite slow if you are trying to complete two tasks at once. - Cucumber Mike (talk) 21:02, 19 March 2013 (UTC)

(ec) You'd want two different computers to do that, or each O/S would compete with the others for resources. I have two different computers (with a switch-box) running here, just like that. I find it's a good way to put old computers to good use. Each computer can be dedicated to do just one thing, so they don't get bogged down. StuRat (talk) 21:05, 19 March 2013 (UTC)

• See VMware, a system that allows you to do just that -- but it's not nearly as easy to set up as a dual boot, and might cost substantial money. Looie496 (talk) 21:09, 19 March 2013 (UTC)