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July 21

Backup autocorrect spelling Word 2010

Hi, I'm doing a clean install of Win 7 and was wondering if there is a way to backup the autocorrect spelling entries in Word 2010?

Thanks, --58.175.33.226 (talk) 02:33, 21 July 2011 (UTC)

If it hasn't changed since word 2007 then this might help.. Vespine (talk) 08:47, 21 July 2011 (UTC)

Sort files into date folders

Hi, I have a bunch of home video files that are just sitting in a loose mass. I was wondering if anyone knew of a program which could automatically sort the files into date folders (the date would be that of creation of the file -> ie when I took the movie).

Cheers, --58.175.33.226 (talk) 06:54, 21 July 2011 (UTC)

I wrote it as a bash script for my photos. The specific syntax depends on the scripting language you like, but it isn't complicated:

1. Set the source folder as SOURCE
2. Set the destination folder as DEST
3. For each FILE in SOURCE
   1. Set CTIME to be the file's creation time
   2. Split CTIME into YEAR, MONTH, and DAY
   3. If DEST/YEAR does not exist, create it
   4. If DEST/YEAR/MONTH does not exist, create it
   5. If DEST/YEAR/MONTH/DAY does not exist, create it.
   6. Set DFILE to be the same name as FILE
   7. While DEST/YEAR/MONTH/DAY/DFILE exists
      1. Append "c" to the front of FILE
   8. Move SOURCE/FILE to DEST/YEAR/MONTH/DAY/DFILE

Now, when you run this, it will copy all of the files in the SOURCE folder to the DEST folder in subdirectories for year, month, and day. -- kainaw™ 14:47, 21 July 2011 (UTC)

Python: sum of sets

In Python, if X is a list of sets, what's the customary way to say X[0] | X[1] | ... | X[-1] ? —Tamfang (talk) 07:46, 21 July 2011 (UTC)

If you had a = [ set([1,2]), set([3,4]), set([5,6,7,8]) ]

then you could take the union of them with reduce (set.union, a)

In Python3 you'd need to import reduce from functools -- Finlay McWalter ☻ Talk 09:54, 21 July 2011 (UTC)

Or, being rather contrarian, set(itertools.chain(*[list(x) for x in a])) -- Finlay McWalter ☻ Talk 12:10, 21 July 2011 (UTC)

Better set(itertools.chain(*a)) -- Finlay McWalter ☻ Talk 12:22, 21 July 2011 (UTC)

Or {x for s in a for x in s}. But the method below is better, I think. -- BenRG (talk) 18:24, 21 July 2011 (UTC)

set.union(*X) works since Python 2.6. -- BenRG (talk) 18:24, 21 July 2011 (UTC)

Gorgeous. I hope I remember that gimmick, it looks like it would have many applications. —Tamfang (talk) 04:38, 22 July 2011 (UTC)

If performance is an issue, I did some profiling (python 2.7). Unsurprisingly BenRG's set.union is the fastest; the better itertools thing and BenRG's set comprehension are both about 65% of its speed; the reduce thing comes at a sluggish 18%. -- Finlay McWalter ☻ Talk 23:30, 21 July 2011 (UTC)

Presumably the reduce approach is slow because it creates intermediate sets of steadily increasing size, making it O(n²) (ignoring log factors). The other approaches amount to s = set(); for t in X: s.update(t), which is O(n) (ignoring log factors). -- BenRG (talk) 22:05, 23 July 2011 (UTC)

How to recover deleted SMS

Is it possible to recover recently deleted SMS from mobile phone that has no blue tooth connectivity say for example an old Samsung SGH X160.If possible will some one give brief idea about the process involved.Ichgab (talk) 11:16, 21 July 2011 (UTC)

This is the area of digital forensics, obtaining the contents of a digital device including deleted files and data.

If the messages are stored on a SIM card, you may be able to use a sim card reader (search Amazon or another hardware supplier) to take a dump of the SIM card contents, which may include the text of the deleted message. Various software is available for analysing SIM cards.

If the messages are in the phone memory, then you need to make a copy of the phone's memory and then search that for possible deleted messages. If the phone has a USB or similar connection, the low-tech way of doing this would be with a bootloader or similar software, which can read and write the phone's flash memory over USB. Such software is available for many phones, though some use encryption. You could then use a hex editor or similar software to study the memory dump. A mobile phone shop that specialises in jailbreaking and unlocking phones would probably have such a tool and might be able to help.

There are experts in mobile phone forensics who specialise in reading data from mobile phones, which can be important in law enforcement, security, private investigations, and civil legal cases. They use a variety of sophisticated and very expensive equipment e.g.[1] If it was really important you may be able to find a private investigator or digital forensics expert. --Colapeninsula (talk) 12:07, 21 July 2011 (UTC)

General Programming and access times

I just had a question about programming in general, with regard to the speed to access/display information. I am asking this not of any language in particular, so i am looking at almost any language whether it is able to be compiled into executable code or if it is more like scripting and is interpreted on run-time.

The question is, is there a general ranking to the speed of different types of data access and retrieval? For instance... can i say that from shortest to longest, it is faster to....

1. Store data to memory/read it from memory (variables, arrays, etc)

2. Read/Write that data to a file

3. Output information to a screen

I am asking in the interest in learning to code a little more efficiently. I was told by a programming professor that output to the screen generally takes more time, so i should alert the user to something only when necessary. Wouldn't it be more efficient, regardless of language, to make an algorithm that works by storing data in memory to use, instead of in files? etc

Thanks

216.173.144.164 (talk) 14:04, 21 July 2011 (UTC)

Storing in memory is faster than storing in a file, until memory is full. At that point the operating system moves the information to a file, and retrieves it when it is needed. On average then, memory is much faster, but a specific store or retrieve may be no better than a file access. Jc3s5h (talk) 14:08, 21 July 2011 (UTC)

Most programming languages store memory in RAM by default; to store memory in a file requires opening a file stream or something along those lines. So I think that's your answer to your last question. --Mr.98 (talk) 14:23, 21 July 2011 (UTC)

Input/Output to memory is much faster than input/output to a disk. The issue is size. A computer usually has far more space on a disk than it has in memory - so you cannot place everything in memory. Output to a screen is a complicated issue. If it is a text-only system, output is not overly complicated. If it is a GUI, output to the screen may required building a window, adding widgets to it, drawing the borders, adding a text widget, filling it with text, adding listeners for mouse clicks, updating the whole GUI, etc... In general, a text-based system will send a lot more information to the user than a GUI system. -- kainaw™ 14:41, 21 July 2011 (UTC)

Depends how you want to define "information" sent to the user. A graphical output of 1024x768 pixels at 60 frames per second at 24 bits-per-pixel is delivering over a gigabit of information to the user each second. You will not find any text-I/O system on the planet that can transmit or receive a gigabit per second with a human in a serial character-stream. On the other hand, the "information density" may be higher in a character-stream, if you abstract semantic meanings from the character-stream in ways that the graphical interface cannot. But, purely from the technical standpoint, no command-line interface on any modern computer is nearly as fast as a graphics bus.

However, most programmers are unable or unwilling to directly program the graphics output; so they rely on windowing toolkits and software abstraction layers. The result is that the maximum information throughput is limited to many orders of magnitude lower than the hardware can support. If you build a window, and print an 80-character string to it, your graphics bus still delivered a gigabit of data each second - but only 80 bytes was "useful" information from the program I/O! The information-density is, by this metric, very very low; and you could have made better use of resources with a serial-port or console emulator. Nimur (talk) 19:34, 21 July 2011 (UTC)

The issue isn't the speed of the graphics bus - it is the overhead of object/struct construction. To pop up a little modal window just to say "Hi dude!", you need to construct the entire window object in memory and attach it to the desktop display and then send that off to the windowing manager for display. Then, the high-speed graphics card will display it quickly. For a text-only display, you call a print command which requires very much less overhead in the terminal control. The worst you'll run into is management of a scroll buffer. -- kainaw™ 00:44, 22 July 2011 (UTC)

Issue with flash security and a CD im using..........

I am running some training software which is essentially HTML pages with embedded flash videos etc. I get an error when i run the main page from the CD.

It says...

Adobe Flash player has stopped a potentially unsafe operation...

The following application on your computer or network: (swf file path) is trying to communicate with this internet enabled location: (html file path)

it says i have to change the settings to allow it to work. However, flash thinks that this is on the internet, so i cant specify a url to allow. allowing all sites doesnt work either. I also tried the loopback address (127.0.0.1) to no avail. how do i allow the content to communicate so i can view it properly? I have current version of internet explorer and flash on win 7.

216.173.144.164 (talk) 15:26, 21 July 2011 (UTC)

If you hunt around on the disk with Windows Explorer you should be able to find the Flash Video files (probably .flv files) and if so you can play them directly with VLC media player. Hopefully the authors of the disk will have chosen sensible names, or sensible locations, for these, so you can know which file corresponds with which training lesson. -- Finlay McWalter ☻ Talk 15:30, 21 July 2011 (UTC)

The problem is that the swf files control navigation to the different pages etc. I fixed it however, by adding my cd drive to trusted locations for development rofl. Thanks anyway!

216.173.144.164 (talk) 15:32, 21 July 2011 (UTC)

802.11n technical question

Quick technical question on 802.11n. Am I right that MIMO is independent for how many transmit and receive channels an adapter has? In other words, a 1T1R adapter (including ones in APs of course) can still have MIMO, although obviously it's limited to 150mbps? I've seen some things which suggest yes but they're not entirely trustworthy (although our article on MIMO also suggests yes to me) and I did read one thing suggesting no. If MIMO requires multiple channels (in other words a 1T1R can't be MIMO), how are two antenna used on a 1T1R adapter? Does one transmit and one receive? Nil Einne (talk) 18:44, 21 July 2011 (UTC)

1T1R refers to number of RF output stages. You can connect one output to arbitrarily many antennas, constructing a passive antenna array. You can have multiple inputs received or transmitted through the same physical antenna using separate frequencies (channels), if your RF input/output PHY supports that broad RF bandwidth. Consider MIMO to be synonymous with FDMA in that case. Nimur (talk) 19:26, 21 July 2011 (UTC)

Firefox sync

I logged into my account for the first time in months, I've changed computers, and I can't find the option to sync up my data to my browser on my new computer. Anyone know where it is? 173.2.165.251 (talk) 18:48, 21 July 2011 (UTC)

Have you tried doing it from inside Firefox? Go to tools>set up sync. Fribbler (talk) 15:11, 22 July 2011 (UTC)

Updating information on the Memorial Sloan-Kettering Cancer Center Wikipedia site.

1. I would like to know if the Memorial Sloan-Kettering Cancer Center Wiki page is protected from being updated?

2. Is there a way to find out who submitted the Memorial Sloan-Kettering Cancer Center Wiki page in case we need permission to update the information?

Davidthelion2 (talk) 20:22, 21 July 2011 (UTC)David

It isn't locked at present (there's no padlock on the top-right of the page, the second tab is 'Edit', not 'View Source', and the edit link works). To see who's edited the page, click on 'History' on the page. CS Miller (talk) 20:27, 21 July 2011 (UTC)

• The Memorial Sloan–Kettering Cancer Center article is not protected
• You can edit it, or you can discuss your changes on the article's talk page talk:Memorial Sloan–Kettering Cancer Center
• In general the best place for questions about Wikipedia is a specific article's talk page, or at wikipedia:help desk: -- Finlay McWalter ☻ Talk 20:28, 21 July 2011 (UTC)

Every page has a visible History, which can be accessed from a tab at the top, showing all editing contributions. In this case a look at the history shows that Davidthelion2 has made about 20 edits to the page over the past week, which have in whole or part been reverted because they apparently contain copyright violations and other problematic material. The right way to proceed is to start a discussion at Talk:Memorial Sloan–Kettering Cancer Center. Looie496 (talk) 23:29, 21 July 2011 (UTC)

And you do have permission to change what is there. This is part of the conditions of the creative commons license that the content was submitted under. Graeme Bartlett (talk) 09:00, 25 July 2011 (UTC)

Slow startup of PC

I have a PC with 2.25GB RAM, 1.38 GHz processor and 160GB hard disk. The OS is Windows XP SP3. Recently, it has started taking a lot of time to start, as compared to a few days back. I even uninstalled a few programs, but it was of no use. The C drive has 26GB free space. Could someone please tell me the reason for this sudden slow startup and how I can get it to start up faster? Zebec 21:41, 21 July 2011 (UTC)

Consider reading this technical document from Microsoft: Troubleshooting the Startup Process. With the information you have provided, it is impossible for us to diagnose anything. But, after reviewing the startup event logs, as explained in this technical doc, you may be able to solve the problem yourself, or at least provide us with the information we need to give any meaningful feedback.

The first step is to identify what stage of startup is taking a long time. You should investigate your System Event Log - read the log, determine what process or event is taking a long time, and then we can proceed to make some suggestions. Nimur (talk) 22:17, 21 July 2011 (UTC)

Another option is to check using the "system configuration utility" - type "msconfig" in the run window (ie start >> run >>msconfig) - here you can see some useful info - the "Startup tab" gives a list of programs that run on start up, whilst the "boot.ini" shows the boot thingy. You might see something on these lists that looks new or unusual. I'd assume that something you've installed recently is causing it. Another possibility is some updated driver that is having difficulty loading. Or maybe a virus? - If you haven't already do a full scan - you could use http://www.microsoft.com/security/pc-security/mse.aspx amongst others to scan.

Defragment the hard drive just in case... When you use Task Manager how much memory is marked as "PF Usage" after startup- for XP I'd expect less than 300MB. If nothing obvious turns up from these - you'll probably need to go to Nimur's event logs above.

Have you done anything different in that last weeks on the computer? Imgaril (talk) 13:06, 22 July 2011 (UTC)

I've used a program called Soluto to get information on what is running during the startup process and how long it's taking. --LarryMac | Talk 13:31, 22 July 2011 (UTC)

It may be loading a lot of unwanted programs during start up, instead of loading them when and if needed. Use Ccleaner to manage and remove what is loaded at start-up. 92.28.245.233 (talk) 19:26, 23 July 2011 (UTC)

Thank you all for your suggestions.
LarryMac:I downloaded Soluto. It showed 33 applications running in the startup. I paused some of them. Then the boot time reduced to 48 sec till the last boot. It shows 22 applications which run at startup which cannot be removed with Soluto (yet). Why is that? And the time varies with each boot. Why is it fluctuating? Also, it takes 48 sec to boot, but it also takes an additional 1min12sec for the icons to come on the desktop. Why is that? Thanks for suggesting Soluto, because it showed all the programs running at startup, which was not the case with msconfig.
Imgaril: I defragmented all the hard drives before posting this question. So it was of no use. I use Norton Internet Security. So can it still be a virus? The PF usage just after startup is 375MB.
I also downloaded Ccleaner and will try it out.
Nimur: Thanks for your advice. I'm trying out all other options now, if nothing else works, I'll go to the logs. Thanks a lot,all the same.
Zebec 21:18, 24 July 2011 (UTC)

July 22

restoring read-only files to read-write

Somehow, I don't know how, all my files in a few folders were made into read-only. Is there a way I can make them all read-write again? (I wonder if it happened due to some combination "shortcut" keys I accidentally typed (being a poor typist)?) The OS is Vista. --Halcatalyst (talk) 01:02, 22 July 2011 (UTC)

You should be able to change it in the folder/file properties. Right-click on a folder or file, then go to properties. Down the bottom is a tick-box option for read-only. - Akamad (talk) 01:27, 22 July 2011 (UTC)

That was easy! Thank you very much. --Halcatalyst (talk) 02:32, 22 July 2011 (UTC)

Radio on the ipad

Hi. Is it possible to listen to BBC Radio 4 on the ipad? Googling left me utterly confused. Thanks, Robinh (talk) 01:25, 22 July 2011 (UTC)

It is. Just open the web browser, go to the Radio 4 website (bbc.co.uk/radio4) and click on the play live. Hope this helps. Rcsprinter (talk) 12:00, 22 July 2011 (UTC)

hi. nope, does not work; when i try, it says I need to download flash, which does not work on the iPad. any other ideas? Robinh (talk) 04:15, 23 July 2011 (UTC)

See here http://faq.external.bbc.co.uk/questions/radio/online_radiohowto/?src=interstitial for non-flash Radio access to BBC Radio. ny156uk (talk) 06:53, 23 July 2011 (UTC)

or get the bbc iplayer app for Ipad (sorry that's probably a simpler solution - it's free too, at least here in the UK). ny156uk (talk) 06:55, 23 July 2011 (UTC)

Thanks for this. Unfortunately I seem to be hitting brick walls (I'm based in NZ, which seems to make a difference). There doesn't seem to be an ipad app that works for radio, and the BBC FAQ doesn't seem to help. Does any refdesker not in the UK have access to Radio 4 on an ipad? Cheers, Robinh (talk) 08:09, 23 July 2011 (UTC)

Are security requirements considered to be a Non-functional requirement

It is certainly on the list in the article, but many elements seem to me to be functional requirements. For example audit, non-repudiation, single sign on, etc. -- Q Chris (talk) 12:40, 22 July 2011 (UTC)

The difference is purely semantic. Various authors of systems-engineering textbooks will use different terminology to describe system design. Nimur (talk) 16:27, 22 July 2011 (UTC)

Security requirements are usually categorized as non-functional requirements. However, depending on the requirement, sometimes specific features, behaviors, and/or design choices are mandated. You can make a good argument that requirements like that are not non-functional. The bottom-line is: categorizing requirements is just a practice for organizing and managing them; it does not affect the substantive criteria that define what an acceptable solution is. The important thing is you have a complete, correct, and well-expressed set of requirements. There is some value in organizing requirements into categories, but beyond a certain point, finding the single "correct" category to put a requirement in may become an unproductive exercise, especially if it involves hair-splitting. --98.114.98.196 (talk) 14:22, 23 July 2011 (UTC)

Facebook down?

I keep getting "Account temporarily unavailable Your account is currently unavailable due to a site issue. We expect this to be resolved shortly. Please try again in a few minutes." Anyone else having problems? DuncanHill (talk) 13:29, 22 July 2011 (UTC)

Nope. But it has been a few minutes since you posted this. --Mr.98 (talk) 14:05, 22 July 2011 (UTC)

I find the site http://www.downforeveryoneorjustme.com/ to be quite useful at times like that. ny156uk (talk) 06:52, 23 July 2011 (UTC)

I don't think that would work in this case. DuncanHill isn't claiming that Facebook is offline entirely, just that they're having some sort of malfunction. DownForEveryoneOrJustMe.Com would connect to facebook dot com, retrieve their page that says "Account temporarily unavailable..." and say "Yup! This web page is still online! It's still serving content!". It's not smart enough to know that the content is just a page explaining that facebook isn't working. APL (talk) 10:16, 23 July 2011 (UTC)

Thanks, sorry I didn't get back sooner. Well, it resolved itself after a few minutes. What was puzzling me was that although I've occasionally have Facebook go down entirely, I've never had the "Account temporarily unavailable" message before. DuncanHill (talk) 16:06, 24 July 2011 (UTC)

what's the best computing language to learn?

Hi folks :) is C++ the best all-purpose computer language to learn if one is interested in a career in comp/sci or programming, or has Java or C-sharp taken over? It's been emotional (talk) 18:22, 22 July 2011 (UTC)

You should learn several programming languages if you intend to become a professional software engineer. After you have learned three or four different types of languages, you should take a break, far from any computers (I recommend a camping trip without any electricity or network connection). And, you should sit alone in the woods, and say, "Am I a Systems Programmer? C : Java;" Nimur (talk) 18:32, 22 July 2011 (UTC)

C/C++ is the most all-purpose language in that if you know the basics of C/C++, you can quickly pick up all the other popular languages. As an example: Technically, I learned assembly first, but my first normal language was C, then C++. In the military, I needed to know COBOL. I picked it up while flipping through a COBOL manual in the truck on the way to the programming office. Then, in college, I needed to know Java. I flipped through a Java textbook and picked it up in a couple hours. A harder one was ADA. I needed it for an Air Force contract. It took me a weekend to pick it up. You don't become an expert programmer in a couple hours, but you "get" the syntax because it is very similar to C/C++. Then, you can quickly look at how it is different from C/C++ and go from there. I see it as starting at the trunk of the programming tree and going out on the branches. If you first learn the tip of a branch, it takes a lot more effort to figure out how to work at the tip of another branch. -- kainaw™ 18:48, 22 July 2011 (UTC)

Thanks, very helpful advice. Nimur, is it a compromise if I just find some place like the one on your userpage? I'm not good at surviving without electricity, although I could probably make do without a network (read: Wikipedia) for a while, just to get some work done :) It's been emotional (talk) 18:59, 22 July 2011 (UTC)

I always suggest that people start by learning a simple, clean, powerful language like Racket or Python. Industry-oriented languages have a lot of cruft that can get in the way of the really important stuff. If the only language you know is some big, heavy thing like Java or C++, you'll tend to focus too much on trivial decisions instead of on getting a good overall design. Picking up new languages is easy, but learning how to think about computation is hard and very important, so learn with as clean and simple a language as possible, not one that was designed to trade programmer effort for faster execution time. Paul (Stansifer) 23:46, 22 July 2011 (UTC)

I think that's good sound advice. Also you should always try scripting the use of other tools first when solving a problem, it's normally far faster at getting an adequate solution and shows up any real problems much quicker than rolling your own. Dmcq (talk) 15:38, 23 July 2011 (UTC)

Norton Anti-Virus

Resolved

I have realised (somewhat to my shock) that over half of my laptop's internal hard drive is given over to Norton's "Virus Defs" folder.

I'm keen to free up that space on the computer. So my question is this: if I move that folder to an external hard drive, how can I make Norton "map" to the new location and find its Virus Defs there? And, of course, force it to update its Virus Defs at the new location, also, whenever it updates? AndyJones (talk) 21:33, 22 July 2011 (UTC)

Either your laptop has a very small hard drive, or you should replace Norton. I'd probably replace Norton regardless, it's awful. ¦ Reisio (talk) 02:10, 23 July 2011 (UTC)

Well I'm personally using Norton Internet Security 2011 and I don't have any problems with it. I don't know if perhaps your experiences are based on versions from about 5+ years ago (which truely were bloated/terrible), but the last few releases haven't caused me any issues or noticeable slowdown, it just works. To the original poster, the definition files should be around 200Mb in total, at least that's what I get based on definitions released a few hours ago. My version is only keeps the latest definitions though so depending on which version of Norton you have it may be storing the previous 2-3 different defintions and thus 3 times that disk space. If you have considerably more space being used than that being used though then it might be worth uninstalling and reinstalling it to see if that fixes the problem. As far as I know though it isn't possible to move the definitions to another drive, probably because they're treated as critical files and therefore must/should be available at all times and as such the C: is the only place for them, but another person may know otherwise!  ZX81  ^talk 02:26, 23 July 2011 (UTC)

Seems to only get worse as time goes by IME. 2011 still needs a "removal tool" to uninstall it after you "uninstall" it, right? :p ¦ Reisio (talk) 07:27, 23 July 2011 (UTC)

To put my question into context, the VirusDefs "properties" dialog tells me it has a "size on disk" of 34.8GB, and contains 15,426 files in 781 folders. The answers above suggest it shouldn't look like that, at all. Is there any merit in just removing the folder (onto a backup disk rather than just deleting), then sending Norton off to do a live update (which would presumably restore the current set only)? AndyJones (talk) 11:43, 23 July 2011 (UTC)

Thank you to those who replied. Problem resolved by using the Norton removal tool. AndyJones (talk) 13:10, 23 July 2011 (UTC)

July 23

Sata power connector

I'm building a computer, and most of it is functional, but when it boots, neither the HD or OD are recognized. The light on the optical drive doesn't turn on, I can't eject either, and the hard drive isn't spinning, so I'm assuming it's a problem with the power somehow. The cable I'm using is a Cooler Master cable that looks like this. I tried swapping in a hard drive I know works, but that didn't work. I also tried switching the SATA power cable for a 4-pin molex, and using an adapter to change that to SATA, but that didn't work either. However, when that same molex cable is connected to the fans, it works just fine. How would I find the source of the problem? KyuubiSeal (talk) 02:36, 23 July 2011 (UTC)

Does the optical drive light come on if you unplug the data cable while leaving the power plugged in? Nil Einne (talk) 08:41, 23 July 2011 (UTC)

I suspect that the fan is more tolerant of power that's outside of specs, like low voltage. Those other devices might even have safety features to prevent operation (which might cause damage) using a defective power supply. Try swapping in a new power supply. StuRat (talk) 14:12, 23 July 2011 (UTC)

I don't happen to have another power supply on hand. I do have a voltmeter though. Would it be safe to test the voltage and current on either cable while it's running? KyuubiSeal (talk) 14:35, 23 July 2011 (UTC)

Sure, that's easy enough for the Molex connector, but trickier for the SATA. Black->yellow should be 12V and black->red should be 5V; note that systems frequently draw maximum power for a few seconds as they boot, so watching the voltages as the system boots (rather than when it's quietly cruising along) can be instructive. That said, in my experience, when the drive-connector rails in a PC PSU are overtaxed the symptom is usually that a given drive starts, spins up, and then is depowered (sometimes a cycle of powerup/down develops). For neither device to even start to spin up would suggest the power isn't getting through at all, or at a very low voltage, suggesting either a bad connector somewhere or a defective PSU altogether. -- Finlay McWalter ☻ Talk 14:58, 23 July 2011 (UTC)

You were right, very little power was coming through. Also, a few minutes after we tested it, there was a huge spark, the fan stopped, and no power came from any port. Could have damaged something if we hadn't disconnected it to test it. Thank you so much! KyuubiSeal (talk) 02:11, 24 July 2011 (UTC)

Facebook - Exporting list of page fans ('likes')

Hi, does anybody know a straightforward way to export a list of people that 'like' a facebook page that you are an admin on? I've had a look through facebook, and range range of blogs and articles about it, and I cant seem to find an easy way to do this that appears entirely white-hat - We don't want to do anything that facebook or our fans might react poorly to.

In my case, I would need to be able to export the public names of several thousand profiles that 'like' the page. This isn't for any devious purpose, the place where I work operates a number of different internal and external digital social platforms, and we want to avoid bombarding people that may have accounts across several of those platforms with the same information. Ideally, if it is possible, I would like to be able to export as a CSV (or anything else easily compatible with Excel).

I can't find anything on facebook that forbids doing this, nor can I find anything that says it is ok to do this.

Facebook does appear to have a tool that allows you to do something similar for facebook groups, but hasn't rolled out a tool for 'pages'.

I keen to hear about any thoughts, experiences or tips you might have.

Thanks Computing helpdesk people. 86.182.254.23 (talk) 11:37, 23 July 2011 (UTC)

Enumerating "likes" certainly seems to be supported by the Facebook graph API (docs). -- Finlay McWalter ☻ Talk 11:46, 23 July 2011 (UTC)

Hi, thanks, I did have a look at that page, but I am afraid to say it mostly went over my head, and I wasn't sure if I could use it to do what I want. Given that you suggest I may be able to use that to pull out the details I'm after, I may invest some time in working out how to use the API properly. Thanks Finlay McWalter 86.182.254.23 (talk) 12:27, 23 July 2011 (UTC)

These APIs are intended for an audience of programmers, most of whom manipulate them through a wrapper adapter specific to whatever programming language they're using. The APIs show that, at least in theory, the information you want is accessible to programs (although I've not read the terms-of-service carefully; API users tend to have to be careful in that regard, lest they be treated as being not entirely white-hat). But if you're not a programmer, and don't have the help of one to hand, the mere evidence that an API exists which could allow a program to do what you want obviously isn't the same as actually having such a program. You may need to recruit a programmer temporarily, if no-one else can find a pre-existing program that uses the API in the fashion you want. -- Finlay McWalter ☻ Talk 14:29, 23 July 2011 (UTC)

Hi Finlay McWalter, thanks for the additional reply. I can confirm that I am in no way what-so-ever a programmer, although, I do pick things up reasonably quickly. If I can't master the programming quickly (which I assume will be the case), I shall ask the powers-that-be how much they want to invest to pull in the data. I really do appreciate your additional advice, it is very helpful. In the words of my peers: "Cheers" (poet, didn't know it etc.), 86.182.254.23 (talk) 17:00, 23 July 2011 (UTC)

Facebook has created a Graph Explorer to walk the Graph (you will need to authorize the app using the 'Get access token' button there first), which might help you see if the data you want is available using that route. Click around a bit or type your page's ID in the input field there to get a bit of information. I haven't been able to find the Likes for a page using it yet though - if I enter a <pageid>/likes, I get an empty list, although I am able to get a list of people liking a specific post by following <pageid>/posts. 82.75.188.107 (talk) 18:27, 23 July 2011 (UTC)

relief map

i wasn't sure where to ask this question but is there any software by which i can make (imaginary) relief maps, very easily in a simcity like way?(i want it for a sci-fi story)--Irrational number (talk) 14:00, 23 July 2011 (UTC)

The scenery generator and fractal landscape articles list a few programs that can do this. -- Finlay McWalter ☻ Talk 14:04, 23 July 2011 (UTC)

Connecting subwoofer to receiver

I've recently upgraded from a plasma TV-based setup to a home cinema with projector, but I'm having trouble connecting my old subwoofer to my new receiver (it is this model). My subwoofer seems to use the same connection as my other speakers (here's a pic]) but there doesn't seem to be a port for it to connect to. Would I have to use some kind of adapter? doomgaze (talk) 15:20, 23 July 2011 (UTC)

Your receiver has a line-level output for the subwoofer. You can use a powered subwoofer (that is, one with a built-in amplifier) with it. If you want to use your existing (non-powered) subwoofer, you'll need an amplifier to drive it. Try searching the web or your favorite shopping sites using "mono subwoofer amplifier" and variations of it. --98.114.98.196 (talk) 16:38, 23 July 2011 (UTC)

And you might find you can get a more modern sub-woofer for less than the amplifier will cost. That's what I did. I got a decent 2.1 system (right speaker, left speaker, and powered mono sub-woofer) for $30. StuRat (talk) 18:11, 23 July 2011 (UTC)

Mm I was going to make that observation too, looks like I'll just replace the subwoofer. Thanks guys, doomgaze (talk) 18:33, 23 July 2011 (UTC)

Missing edit links in Reference Desks

Wikipedia seems to a longstanding problem with sporadic disappearances of page and section "edit" links. Right now none of the Reference Desks has any edit links, either for the page or for individual sections. (I'm relying on a workaround to post this.) Does anyone know what the cause of the problem is? --98.114.98.196 (talk) 17:25, 23 July 2011 (UTC)

It seems to only be a problem for anonymous I/P's, like yourself. I suspect it's the lowest level of protection, to prevent spambots from plastering these pages with ads. You can sign up with Wikipedia for free, to avoid this problem in the future. StuRat (talk) 18:02, 23 July 2011 (UTC)

There's zero evidence for that and it seems rather unlikely since the foundation doesn't tend to play nasty tricks. All evidence suggests it's a bug that no one has tracked down. The reason it only affects anons is likely because only they use the cached version. Nil Einne (talk) 18:56, 23 July 2011 (UTC)

It's still happening here too. Nothing seems to come of the threads on Village Pump either. Someone suggested filing a bugzilla report, I've no idea how to do that though. 82.43.90.27 (talk) 21:22, 23 July 2011 (UTC)

I do like to call it as "fake protection" or "spoofed/cloaked protection". That means, the page seems to be protected and you cannot edit it, but actually can. Testor Ploa (talk) 04:05, 24 July 2011 (UTC)

No, no, it is not true that you cannot edit a page if the edit links of sections are not visible (simply press the Edit tab at the top), and missing edit links do not only affect anons. See Wikipedia:Purge for the cause and the solution. --Espoo (talk) 16:08, 8 October 2011 (UTC)

Should routers make faint noises?

Should DSL routers with a DC input make very faint high pitched noises, audible only when you put your ears against them? What causes the to make this noise? Bahr456 (talk) 21:05, 23 July 2011 (UTC)

I often hear the flyback transformer in old television sets, and very often hear capacitors audibly squealing inside the switching power supply in a lot of small electronics. I particularly noticed a ~15 kHz squeal on the power supply of my old Linksys 802.11b wireless router. Although such noises indicate a power supply whose design or manufacturing-tolerances were "imperfect," they rarely indicate a failure or imminent problem. "Theoretically," acoustic resonance in a capacitor may reduce its expected lifetime, but I've never seen this in practice.

The root cause, in many cases, is a sort of 'piezoelectric effect' In the power supply capacitor. A signal is passing through the cap, which by design should (usually) be outside the audible range - say, 1 MHz, for switch mode power conversion. Due to imperfect design, some signal may leak into an audible band. Then, because the capacitor dielectric is subject to a mechanical force due to electrostatic attraction, the acoustic frequency electromagnetic signal can cause an acoustic vibration of the capacitor dielectric. This can cause a faint audible buzz, hum, or squeal.

There are probably dozens of other possible root causes for faint squeals or hums in your router, but this one seems most common in my experience. Nimur (talk) 04:16, 25 July 2011 (UTC)

screen recording device

Taking note that the people here are experienced with computers, could you please recommend to me some free software that records what you do on the screen that does not slow down the computer significantly nor advertise itself in the playbacked video? Thanks. --Thebackofmymind (talk) 21:32, 23 July 2011 (UTC)

CamStudio or VLC would be my recommendations. In VLC to record the screen go Media - > Convert / Save -> Capture Device - > Capture Mode -> Desktop. Both programs require some processing power to operate, which may slow down your computer. I don't think there's any way to work around that without upgrading your computer. AvrillirvA (talk) 23:15, 23 July 2011 (UTC)

Check out Comparison of screencasting software.

APL (talk) 06:11, 24 July 2011 (UTC)

To avoid a significant slowdown, you'd need a very low frame rate and/or resolution/color depth, or to give up on using the computer to record itself and use an external video cameras instead (or maybe clone the images going to the monitor and send half to another computer's video input, and have it store the images). StuRat (talk) 06:16, 24 July 2011 (UTC)

July 24

Speech recognition

I used a speech recognition software to recognize the lyrics of a song and the result was incorrect. Any idea? Testor Ploa (talk) 04:01, 24 July 2011 (UTC)

Not particularly surprising. As our speech recognition article indicates, this works best in the context of a narrowly-defined field, where the vocabulary is small, and the semantics clear. Song lyrics are almost the polar opposite of this. Time flies like an arrow, fruit flies like bananas, and my love is like a red red rose... AndyTheGrump (talk) 04:36, 24 July 2011 (UTC)

Time flies like an arrow... but we can decelerate it. Testor Ploa (talk) 04:51, 24 July 2011 (UTC)

Even people with good hearing have difficulty figuring out song lyrics. See mondegreen.--Shantavira|^{feed me} 05:38, 24 July 2011 (UTC)

I'm afraid this is just a limit of the technology. Even with no background noise (musical accompaniment counts as 'noise' in this context) speech recognition is far from flawless. APL (talk) 06:17, 24 July 2011 (UTC)

That's a good point. The human auditory system is readily and instinctively able to distinguish language from background noice/musical overlay and process it effortlessly. On the other hand, computers so far struggle immensely with this distinction and processing. Simply, a computer can't do any better making out the lyrics of some recording than your ear can.--el Aprel (^facta-_facienda) 21:53, 24 July 2011 (UTC)

Chances of tracking down attempted SQL injection

OK so i did a stupid think i tried "how to hack" youtube video and tried to hack as an Admin onto a website. After an "Admin" username and string [1'or'1'='1], this message in red letters popped up that this security breach attempt was forwarded to their IT department.

I was in firefox, with private browsing enabled (similar to Google incognito, http://support.mozilla.com/en-US/kb/Private%20Browsing), and had Tor, which allows me to connect to multiple anonymous servers (bouncing your communications around a distributed network of relays). What are the chances I can get tracked down for this?--DSbanker (talk) 04:11, 24 July 2011 (UTC)

I suspect this will depend very much on the website you were trying to hack. If it was some random forum, you may very well get away with it (scary warnings don't necessarily mean much), but if it was the CIA, don't make any long-term plans. But why would you think that YouTube was a sensible place to look for help on this in the first place? Anything there is more or less certain to be either wrong, simplistic, or just plain useless. AndyTheGrump (talk) 04:22, 24 July 2011 (UTC)

It was actually the website of a midsize business in another state.

i am 15 years old, and yes what i tried was stupid. But i did plan for this scenario to come up and planned to be untraceable, as i am beginning learning python and etc. The only problem, i connected to Tor from a home IP address (stupid) Correction: this should be called "Chances of tracking down attempted SQL injection?"--DSbanker (talk) 04:26, 24 July 2011 (UTC)

It isn't just stupid, it is wrong. Breaking into websites is as bad as breaking into houses. If you develop criminal habits at the age of 15, you are going to find it hard to unlearn them. Give it up! There are better ways to get your kicks. Looie496 (talk) 05:43, 24 July 2011 (UTC)

If you were properly using TOR, I think the chances of them tracking you down would be pretty low. Even without TOR they'd need to contact the FBI who would need to get a warrent to your ISP's records and then confiscate your computers to verify that it was you and not someone controlling your machine remotely. Tor's biggest known vulnerability requires a number of "bad apple" nodes hidden within the network. I'm sure a number of law enforcement agencies have done this, but I don't think they'd "out" them for such a juvenile and unsuccessful attack.

To be honest, the fact that they've got an error message specifically designed to be scary makes me think that they get a lot of people trying it. So I wouldn't lose too much sleep over it if I were you. APL (talk) 06:07, 24 July 2011 (UTC)

I'm a bit annoyed here. We ought not to be assisting people with criminal activity, or helping people to avoid facing the consequences of criminal activity. Looie496 (talk) 17:31, 24 July 2011 (UTC)

I'm just asking something here. I am not gna be trying it again.--DSbanker (talk) 23:59, 24 July 2011 (UTC)

It's not clear that the OP violated any laws (even if he/she had gotten in, cybercrime is a really problematic area, esp. with mere intrusion into a private server). We're not assisting anything illegal in any case. We're telling them that they aren't going to be tracked down anytime soon for such an amateurish little thing. Which is undoubtedly true.

I will point out that one of the first things I did when learning about SQL injection (which I started SQL programming) was to try a rather simple injection on a website I was using, and was shocked to find that it was wide open exposed. I sent the sysadmin an e-mail and they patched it up. Nobody tracked me down to arrest me. It was a good lesson. --Mr.98 (talk) 01:33, 25 July 2011 (UTC)

...and what would the OP have done if their hack had been successful? People have been arrested and convicted to prison terms for hacking. Like Looie, I don't think we should encourage criminal activity. Astronaut (talk) 15:01, 25 July 2011 (UTC)

I didn't get in, and I don't plan to do anything of the sort again. I was just going to see if what I saw on YouTube worked. I was just fooling around, which was stupid. Il confine my ideas of such activities to theory.--DSbanker (talk) 15:43, 25 July 2011 (UTC)

If you want to become an ethical penetration tester, want to become a sysadmin or are just interested in the field, practice on 'intentionally vulnerable' systems like OWASP WebGoat or Metasploitable, which are legal training kits intended for training pentesters, security consultants and security-minded sysadmins, running in an isolated virtual machine on your own computer. Never practice on someone else's live system without permission. CaptainVindaloo ^{t c e} 16:21, 25 July 2011 (UTC)

Hey thanks for info on that stuff! really appreciate it.--DSbanker (talk) 16:41, 25 July 2011 (UTC)

A command for checking how much memory a program uses during its runtime (in Linux)...

Hi! I'm a bit new to using Linux and the command-line, but I'm already falling in love with it. I have a question though: if I want to find out exactly how much time a program takes to execute, I can simply use the very convenient time utility. Is there a corresponding utility for memory? Like, you type something like "memory something", and it lists the maximum amount of memory "something" needed during runtime? The reason I want this is just as an easy way to check if some optimizations to a program I'm making is actually working. I realize that there are much better ways to do it, but I just want a very quick and dirty way to get some idea about it, much like how the time-command gives you a quick and dirty way to find out if your program becomes faster. 80.216.71.133 (talk) 07:45, 24 July 2011 (UTC)

valgrind, by default, provides a basic summary with the info you're looking for. Moreover valgrind can report all kinds of stuff, to an overwhelming level of detail. Incidentally, once you feel "time" isn't giving you enough detail of where the time is being spend, gprof is very informative. Equally strace (which shows system calls and their arguments) and ltrace (which does likewise for library calls) can be very informative. -- Finlay McWalter ☻ Talk 10:01, 24 July 2011 (UTC)

To be on the this topic, is there one more detailed (for Windows) than Task Manager in Windows (other than Sysinternals) that is rather cheap on memory resources? General Rommel (talk) 11:05, 24 July 2011 (UTC)

Purify is very good. -- Finlay McWalter ☻ Talk 11:28, 24 July 2011 (UTC)

How about top? Also, vm_stat on some Linux/Unix platforms, though that doesn't break memory down by process, it does show different types of page allocations, which may help diagnose performance issues. Nimur (talk) 03:26, 25 July 2011 (UTC)

Games that spontaneously alt-tab

I enjoy the game Heroes III. (Yes, even though it's old.) Once in a while, though, it will dump me to the desktop. I can easily alt-tab back to it and continue where I left off, but recently I've been trying to find out why it happens - checking for malware, turning off various services and so on. Does anybody know, is this:

• A known bug in Heroes III,
• A known side-effect of any specific spyware,
• A known problem with some part of Windows XP?

I've sometimes observed the same thing in other games, though that might be coincidence. I've never known it happen in any of the various art programs and IDEs I run, only while playing games - and not very often. It might be related to programs that run full-screen, although I've never noticed it affect Blender.  Card Zero  (talk) 11:40, 24 July 2011 (UTC)

A guess: when you run old games in fullscreen mode, often they have to switch resolutions and video modes and etc. as they segue between different parts of the game (e.g. menus, the main game, whatever). I seem to recall on my old computer that sometimes these transitions would bug out or fail or something. Does it happen while just playing, or is it something that happens when switching between different resolutions? Does it happen while you are actively playing, or when you've not done anything for awhile? --Mr.98 (talk) 12:24, 24 July 2011 (UTC)

Good thought, but no - today it happened just before some AI-controlled vampire lords flew over my castle wall to attack something, which doesn't involve any sort of switch between screens. I have a vague feeling that it might always happen just before a sound is played, and so I am suspicious of my sound driver, but I don't find the idea very plausible (lots of sounds are played in the course of a game, and why would the sound driver suddenly dislike one of them, and ... so I'm just being superstitious really). I think it can happen while the game is idling, too.  Card Zero  (talk) 12:34, 24 July 2011 (UTC)

Could it be a different application (eg messaging) trying to get your attention, which would switch you out of the fullscreen game ? Unilynx (talk) 14:33, 24 July 2011 (UTC)

do you know how to check the event log? There might be a clue there. Vespine (talk) 05:06, 25 July 2011 (UTC)

laptop booting

my laptop bios wont accept the os which i put...aft pressin enter wen it prompts to press any key for boot it shows a blinking cursor with a black background.....help me out pls.... — Preceding unsigned comment added by 59.161.181.224 (talk) 14:28, 24 July 2011 (UTC)

What OS are you trying to boot? Can you boot any other OS? This problem generally means that the bios can't locate or read the boot commands, but there are many possible causes, including hardware failures, disk corruption, or an incorrectly set up boot sector. Looie496 (talk) 17:25, 24 July 2011 (UTC)

wget article history

How would you use wget to output all the IP contributors to let's say the Example article to a text file ? Drogonov 19:42, 24 July 2011 (UTC)

I don't think that's a task wget could do on its own. Wget is just a download program, it can download the history page but you'd need to use some other program to process it, extract ip addresses, and output them to a text file. Maybe something like grep 82.43.90.27 (talk) 22:20, 24 July 2011 (UTC)

As long as Drogonov didn't need to do anything more, wget+grep should be enough. But if the real goal is to do more processing (e.g. to retrieve and analyse the contributions of the IP contributors) then scraping the HTML becomes a pain. The Mediawiki API (and the accompanying wrapper libraries for various programming languages) makes doing this kind of thing much, much easier. -- Finlay McWalter ☻ Talk 23:44, 24 July 2011 (UTC)

Linux distribution system requirements

I have an old Windows 98 second edition PC that is idling and I'm thinking about trying out Linux on it. Is there a list of hardware system requirements for the older Linux distributions? In particular, I'm considering Ubuntu. My PC uses Intel 82443BX Pentium (r) II processor with 128 MB Ram & 19 GB hard disk. Thanks. Axl ¤ [Talk] 20:24, 24 July 2011 (UTC)

That's well below the recommended requirements for Ubuntu Desktop. A lightweight Linux distribution like Puppy Linux should be okay. -- Finlay McWalter ☻ Talk 20:30, 24 July 2011 (UTC)

But if you intend to use the machine only as a (slow) server, it's just within the requirements of the Ubuntu Server CLI. -- Finlay McWalter ☻ Talk

Finlay, thanks for your answer. Is even the oldest version of Ubuntu too advanced for my machine? What about Windows XP? I think that Windows XP should work, right? Axl ¤ [Talk] 21:28, 24 July 2011 (UTC)

Running an older-than-current version of Ubuntu is a bad idea; only one older version is still supported, and it's not that old. You're talking about a machine that's at least 13 years old; asking it to run anything other than a very low-end system isn't practical. If you want to eke out a few more years of minimal functionality from this thing, use Puppy Linux. It might just run XP, but XP licences are hard to get and would be wasted on this thing. Equally any Linux on this thing is going to be a basic experience at best. If you're curious about what a modern mature and feature-rich Linux experience is like, but don't want to commit a nice new-ish machine, you can install Ubuntu on Windows (where it's kinda like an application) using Wubi (which comes on the Ubuntu install disk); this won't damage your existing Windows install. As to the Pentium II - frankly I'd either put this thing in the bin or I'd get it running Win98 nicely and pack it up carefully and put it in the attic, and in 20 years it'll be worth donating to a museum. -- Finlay McWalter ☻ Talk 21:53, 24 July 2011 (UTC)

Okay, thanks Finlay. Axl ¤ [Talk] 22:05, 24 July 2011 (UTC)

You could try a LiveCD to try out something like PuppyLinux without installing it. See List_of_live_CDs#Linux-based. 2.101.4.222 (talk) 09:36, 25 July 2011 (UTC)

Yeah, I'll try one of the lightweight versions from USB, maybe Lubuntu. Thanks. Axl ¤ [Talk] 18:24, 25 July 2011 (UTC)

See also Lightweight Linux distribution and List of Linux distributions that run from RAM. 2.97.216.222 (talk) 21:03, 25 July 2011 (UTC)

July 25

Does logging in enhance access to this desk?

Hi I noticed that when I am not logged into Wikipedia, I can only see up to July 21, but when I am logged in, it takes me to the current forum. Is this supposed to happen--DSbanker (talk) 00:01, 25 July 2011 (UTC)?

No. —Jeremy v^_^v ^{Components:V S M} 00:09, 25 July 2011 (UTC)

We have previously noticed that (either by design or by accident) that many users who are not logged in see old, cached versions of the reference desks. That may also entail that the page appears read-only. If you're curious about details, search this page's archives for "caching" and "wikipedia" - if you need help finding some of the numerous prior detailed discussions, I or one of the other refdesk regulars can probably track down the archived discussions. Nimur (talk) 04:24, 25 July 2011 (UTC)

Some of the archived discussions;[2][3][4] [5]There's also a thread further up this page about it [6] and some threads from Village pump;[7][8]. The workaround at the moment is to purge Wikipedias server cache, see WP:Purge for how. This will force the current version of the page to appear, and you may have to keep doing it as for some reason pages often revert back to the out of date versions. Something really needs to be done about this entire situation, it has been going on for ages now AvrillirvA (talk) 10:40, 25 July 2011 (UTC)

Yes, this is happening to me as well, a lot of old revisions of pages are appearing, and as read-only. 80.123.210.172 (talk) 14:50, 25 July 2011 (UTC)

Ideal programming language(s) for beginning bioinformatics

I am a high school sophomore and visited a professor in the molecular biology sciences who is also an expert programmer. (He builds robots, biochips, and a bunch of other cool gadgets.) In discussing other things, he urged me to learn Python programming, and now im very interested in computer science, and progressing rapidly. I know Python is a powerful language for its simple syntax. But if I want to go into bioinformatics (especially to use the tool http://www.ncbi.nlm.nih.gov/BLAST/) and computer programming in general, maybe even study cybersecurity, is it an ideal language to start with? or is C/C++ a better choice?--DSbanker (talk) 15:33, 25 July 2011 (UTC)

In the long term, it doesn't make any difference. The skill you hope to acquire is programming; it's a bit like driving - you can learn to drive in a mini or a van and then drive anything in between, with a skill that's a head-start for learning to ride motorcycles or drive big-rig trucks. Any decent programmer can change to another language without a great struggle. -- Finlay McWalter ☻ Talk 16:11, 25 July 2011 (UTC)

Are there programming languages that would be especially bad choices for a beginning programmer; either because they are especially difficult to learn or eccentric in their approach and thus not easily transferable to other languages? Wanderer57 (talk) 16:40, 25 July 2011 (UTC)

Yes. There are many. Mumps is one that I like to pick on for being a terrible language to learn. Then, there are ones that are languages that are great for their intended purpose, but trying to use them as a general all-purpose language is a mistake, such as Lisp, Perl, or QBasic. -- kainaw™ 16:45, 25 July 2011 (UTC)

Lisp is definitely not a special-purpose language! Because of their macro systems, Lisp-like languages are perhaps the most general-purpose languages possible. A number of schools teach Scheme (a Lisp-derived language) as a first language because they're nice and simple, yet powerful. Paul (Stansifer) 18:46, 25 July 2011 (UTC)

This is just proof that any claim that anyone makes in the realm of computer science is certain to be met with contradiction without sufficient explanation. Scheme, as mentioned, is a dialect of Lisp that reduces emphasis on list processing and increases emphasis on minimalism and extendability. As such, it is more general purpose than Lisp - which is why I didn't include Lisp in a very short list of programming languages that are primarily used as specialty languages. Similarly, I didn't include ML, which is my preferred dialect of Lisp. -- kainaw™ 19:41, 25 July 2011 (UTC)

There's a claim (which to my mind is a total myth) that the first language you learn somehow warps your mind (like some kind of neuroplastic Whorfian fugue) and that if you learn the wrong language (which is whatever language industry actually wants right now, and thus is unfashionably associated with drab accounting programs) you're forever scarred. If this were true, programmers of my age, who learned on a motley collection of BASIC, 8-bit assembly, forth, and some pascal, should by rights be gurgling imbeciles, our code neither (as the song would have it) functional nor elegant. In practice there's mostly a continuum from the mechanical end (VHDL, asm, C) through the procedural (pascal, python, javascript, java, perl) to the functional (ml, haskell, scheme) and logical (prolog). Although most people end up making their living writing C++ or Javascript or the like many universities try to start their CS (and sometimes EE) people off with lisp or haskell (and I've heard of places, at least a decade or so ago, still starting people with prolog). It is a bigger jump from Haskell to C than from Python to C, but clearly plenty of people of reasonable intelligence graduate from one to the other without their minds exploding. A friend of mine worked for decades in Cobol, a language decried by the fashionistas as everything that's wrong with the world, but in practice the programs he was producing did complex distributed time-sensitive operations; the programs probably looked rather ugly, but the ideas they represented were beautiful. There are some wilfully abstruse ghetto languages, but in general any language of moderate maturity, whose creators designed it to get stuff done and not just to make a point, should be just fine. -- Finlay McWalter ☻ Talk 17:08, 25 July 2011 (UTC)

I don't know why I didn't think to mention this above, but I work in bioinformatics as a programmer. The language that I use about 90% of the time is PHP. I could use Python or Ruby or any scripting language. I use PHP because many of the libraries that I had access to when I started where in PHP and I'm not in the mood to rewrite them. The reason for using a scripted language instead of a compiled one is that much of the programming is based on some theory that some doctor has. So, a quick script is written to compare this, that, and something else and pump out a CSV file that the doctor can play with in Excel. On a day when I'm in a good mood, I'll even dump a PDF report with pretty graphs. The scripts are one-time use, so I don't have any need to compile and store a lot of executables. The runtime hit for scripting isn't important. I just start the script and move on to the next project. When the script eventually ends, I send the results off to the doctor. -- kainaw™ 19:45, 25 July 2011 (UTC)

I think starting with Python is perfectly fine. I wish it was around when I started programming. Well, it was around when I really started learning programming, but not to the point of being widely used. After Python, I'd look into Java. That's another language school like to use as a starting language, and it has a lot of usability for cyber-security. --Wirbelwindヴィルヴェルヴィント (talk) 00:09, 26 July 2011 (UTC)

A lot of the bioinformatics grad students and faculty I know like to use the R statistical programming language, particularly for when they use our HPC clusters. I agree that Python is a great way to get into programming, though, particularly since SciPy is almost as fast as the Matlab toolboxes that perform the same kind of operations. -- JSBillings 00:22, 26 July 2011 (UTC)

It depends with whom(projects are generally written in the same language) and with what you'll be working with. There are beginning books specifically for bioinformatics:

• Robert Gentleman (2009). R programming for bioinformatics. CRC Press. ISBN 9781420063677. Retrieved 25 July 2011.
• James D. Tisdall (2001). Beginning Perl for bioinformatics. O'Reilly Media, Inc. ISBN 9780596000806. Retrieved 25 July 2011.
• Jon Ison; Ison/Rice/Bleasby; Alan Bleasby (1 March 2008). Bioinformatics Programming with EMBOSS. Cambridge University Press. ISBN 9780521607247. Retrieved 25 July 2011. {{cite book}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
• Mitchell L. Model (23 December 2009). Bioinformatics Programming Using Python. O'Reilly Media, Inc. ISBN 9780596154509. Retrieved 25 July 2011.
• Ruediger-Marcus Flaig (2008). Bioinformatics programming in Python: a practical course for beginners. Wiley-VCH. ISBN 9783527320943. Retrieved 25 July 2011.
• Harshawardhan Bal; Johnny Hujol (2007). Java for bioinformatics and biomedical applications. Springer. ISBN 9780387372358. Retrieved 25 July 2011.

Depending on how intensive the task, you may need to learn assembly for CPU and GPUs which are increasingly being used such as CUDA.Smallman12q (talk) 01:48, 26 July 2011 (UTC)

What is bioinformatics?

This question is a followup to the previous one.

I looked up bioinformatics and read: "Bioinformatics (i/ˌbaɪoʊˌɪnfərˈmætɪks/) is the application of computer science and information technology to the field of biology."

To me that field is as wide as all outdoors. Is it really so broad as that? Thanks. Wanderer57 (talk) 03:07, 26 July 2011 (UTC)

Well, no. I think it would be more accurate to say that it is the application of database technology to biology. That might be a bit too limited, but the other is certainly too broad. Looie496 (talk) 03:22, 26 July 2011 (UTC)

Problem synching Google Calendar & Android phone

I have an Android phone, and use Google Calendar (which I had been using online for some time before getting the phone). Now, most of the time it synchs fine, but twice now I've found that appointments are disappearing from the calendar as seen on the phone (they are still on the calendar online). What might cause this, how can I stop it happening, and most importantly is there a way to make the phone pick up the events again easily? Thanks. DuncanHill (talk) 19:46, 25 July 2011 (UTC)

On my phone, in calendar, I hit the option button, select more, select calendars, and I can see a sync/visible icon next to each one. Then, I can set which ones are synced and which are visible. I can also see if they are in fact synced. Are the missing events from an unsynced account? -- kainaw™ 19:57, 25 July 2011 (UTC)

No, they are from calendars which it says are synched (they've got a tick in the bx next to their names). DuncanHill (talk) 20:01, 25 July 2011 (UTC)

After using Windows, Ubuntu cursor breaks

I dual boot my laptop with Ubuntu 11.04 and Windows 7. I use the Ubuntu partition a lot more, because I prefer it, it runs faster, it has all my files on, etc. But sometimes I run Windows-specific software/games, and have to go back to Windows 7.

However, every time I use Windows, the next time I load Ubuntu, the cursor jumps randomly around the screen and I have to restart using Ctrl+Alt+Delete or the button on my laptop. After a restart, it works fine.

This is an annoyance, and I wondered if anyone had any idea what causes it and/or how to fix it. Dendodge _T\^C 19:59, 25 July 2011 (UTC)

IGMP and PIM

Can someone please present a brief explanation of the roles of IGMP and PIM in a network and when would one or both be used? The respective articles do not relate each other. Thanks in advance. 81.193.153.78 (talk) 22:26, 25 July 2011 (UTC)

July 26

privacy & google maps street view

Looking at

this street view on Google Maps, I just see some ordinary boring houses; then I click on the white arrow to move further in the direction at the right side of the picture and see this ordinary-looking house, and click on the arrow again, and there's nothing unexpected; and so on, but then this one starts to show something different, and here something's definitely not in focus, and similarly here, and here, that's coming to an end, but not quite yet, and the next building is not concealed, but we're not past all that yet, and now we've moved on, and we're back to normal here.

Is this

• a problem with focus; or
• done deliberately for the sake of privacy because whoever lives there demanded it; or
• something else? Michael Hardy (talk) 01:34, 26 July 2011 (UTC)

Quite a few Germans didn't want their houses on Streetview: http://searchenginewatch.com/article/2050481/244000-Germans-Demand-Removal-of-Google-Street-View-Imagery Unilynx (talk) 05:13, 26 July 2011 (UTC)

The Streisand effect may be of interest to you as well. Dismas|^(talk) 05:28, 26 July 2011 (UTC)

Reliable Power Supply Unit

I'm planning on building a computer that requires 280W of power (actually more like 200W, but I like to be conservative). I'll be using this computer at a site with unreliable power produced by a small generator. I desperately need a reliable power supply unit that won't fail under larger-than-normal fluctuations in the amplitude, frequency, etc. of the input power. Can anyone recommend a PSU that has comprehensive protections built-in, and that produces a nice, clean output voltage despite "dirty" input power? --140.180.16.144 (talk) 05:24, 26 July 2011 (UTC)

Pulling up a nickname history on IRC

I was told that /who is the command to pull up the history of all usernames used on a hostmask. I tried that on my own; didn't work. (Someone else managed to succeed on that one, however.)

It should say "Nicknames seen on (hostmask): (list of all nicknames.)"

What exactly is the command that I type to get this? Is it even a "/who?" --70.179.165.67 (talk) 05:30, 26 July 2011 (UTC)