Wikipedia:Reference desk/Archives/Computing/2009 July 6

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July 6

ActiveX on Wikipedia

The company that I work for disabled Flash and ActiveX for all our web browsers about 6 months ago. Until recently, Wikipedia had no issues with this. Well, one small issue is that I never see the WP logo in the top left of the page. Anyway, something has possibly changed at WP because as of tonight, every time that I go to a new page, I get a warning saying that ActiveX controls are not permitted with my browser's security settings and that the page may not display properly. I can't change policy here at work but is there some work around for this on WP? Can I change one of my preferences here so that I don't get this message twice with every page here? (yes, I get the message twice with every page.) Thanks, Dismas|^(talk) 00:30, 6 July 2009 (UTC)

This came up at WP:VPT#Why is there ActiveX on WP?. Algebraist 00:59, 6 July 2009 (UTC)

Well, that helped a little. I took the suggestion of disabling the auto suggestions in the search box and now I only have to clear that error message once per page instead of twice... Thanks for the link, Dismas|^(talk) 02:47, 6 July 2009 (UTC)

Question on size of English Wikipedia

If one added up all text, images and other media in all the 2.7 million mainspace articles on en.wp, what would the total size be? Where can I find this out? Muchos appreciated RD. 99.231.25.27 (talk) 03:08, 6 July 2009 (UTC)

Wikipedia:Size of Wikipedia. Algebraist 03:10, 6 July 2009 (UTC)

Looked there already. It doesn't have it. 99.231.25.27 (talk) 03:17, 6 July 2009 (UTC)

The latest dump of the plain wikicode of all articles runs to five gigabytes (compressed). That doesn't include media files, some non-article pages, or history (the history dump was 2.8 terabytes last time it worked, back in '08). It's hard to find figures on the total size of media used on en.wikipedia, partly because many of them are hosted on commons. 03:26, 6 July 2009 (UTC)

To complicate things... Many of the media files are on commons, not wikipedia. So, does this question want to include only the media actually on wikipedia or all media pulled in from commons? -- kainaw™ 12:57, 6 July 2009 (UTC)

Missing file: NTDETECT

I recently deleted a file from my computer called "NTDETECT", found right in the C: drive. The computer runs Windows XP SP3. I had Googled the filename "ntdetect.exe", and the sites that came up suggested it was malicious, so I deleted it. Bah! Foolish of me! Apparently this is a necessary component for bootup. Next time I restarted, the computer was stuck in a bootup loop. It cycles through two screens:

• One with the manufacturer logo which says

BOOT Menu: <F10>

BIOS Settings: <F2>

• The other with the info on IDE, Bus Nos., Slave/Master designations, etc. which says at the bottom

Press F11 to start recovery (which is followed by a counter)

How can I replace this crucial file? I don't have a boot disc. There is a partition on the hard drive for System Restore—but doesn't this format the drive before re-installing the OS and system files? — Twas Now ( talk • contribs • e-mail ) 05:05, 6 July 2009 (UTC)

Can you create a BartPE disk? Simply copy ntdetect.exe from another computer and use your BartPE CD to copy it over to C:\. --wj32 ^t/c 06:43, 6 July 2009 (UTC)

Or even better, a Knoppix or Ubuntu LiveCD. --antilived^{T | C | G} 10:39, 6 July 2009 (UTC)

I used a BartPE disk to try booting up. I checked on the computer I'm using now that the file ntdetect.com (it's a COM file) is on the boot disk. It got me out of the loop, but didn't boot up. It took me to a screen that ended with:

[DR-DOS] A:\

So I typed:

copy e:\i386\ntdetect.com c:\ (e: is my CD drive)

However, it says that the file is not found. I'll try putting the bad hard drive into this computer, copying the file, and see if that works. 99.225.38.10 (talk) 14:46, 6 July 2009 (UTC)

That seems to have worked. Thanks for the tip on BartPE! I have to ask though, since my computer has SP3 and the BartPE disk is supposed to be SP2, will this cause any problems? — Twas Now ( talk • contribs • e-mail ) 15:20, 6 July 2009 (UTC)

Laptop battery life

Is it true that using a laptop on battery for a long time and charging it only when it becomes low , increases the battery life? Shraktu (talk) 11:02, 6 July 2009 (UTC)

Yes and no. It depends on the battery type that is being used. The article Lithium-ion battery has some useful info, infact the section Lithium-ion battery#Advantages and disadvantages has more info. Basically some battery technologies (in general older battery products) used to like the deep-cycle, but these days it's different. 194.221.133.226 (talk) 11:47, 6 July 2009 (UTC)

WinTV Software Alternatives

I have a USB WinTV Nova - T stick with the correct drivers on cd. I am wondering, is there any alternatives to the wintv software for actually viewing channels? Like free, open source alternatives. This is for Windows XP / Vista computer. Thanks --

You can try DScaler and see if your device is supported. --24.162.196.86 (talk) 06:29, 8 July 2009 (UTC)

Hibernation

What is the difference b/w hibernation and stand by in Windows shut down options?Shraktu (talk) 11:53, 6 July 2009 (UTC)

In hibernation the RAM is written to hard disk before power is turned off. When you turn it on again, RAM is brought back to the earlier state and you can resume your unsaved work from there. Sleep mode (standby) is not a state of "power off"—RAM is still active and consumes some power but other unnecessary components are turned off. —SpaceFlight89 (talk) 12:09, 6 July 2009 (UTC)

Outlook 2003 IMAP warning

right I have two computers with Outlook 2003 working with the same mailbox via IMAP. There are many mails, so one computer often shows IMAP server notifications "Account is over quota" (see picture). Currently, I can't clean the mailbox, so I need a way to temporary disable these notifications which are annoying. On another computer (same version of Outlook, same mailbox), those notifications are much less often. Can I somehow disable these notifications of make them appear less often on the first computer? Please don't tell me to clean the mailbox, currently it's out of question for me. 0xFFFF (talk) 11:59, 6 July 2009 (UTC)

Go into the mail server and change the quota. Do you really believe that you can make a change on your computer that will somehow magically change the quota on the server or allow your computer to somehow get magical status and tell the server that you don't need no stinkin' quota? The warning is not something your computer is doing to annoy you. The warning is there because you have too much email and you are over the quota allowed by the server. In other words, the server is the source of the warning, not your computer. -- kainaw™ 12:55, 6 July 2009 (UTC)

I totally understand the meaning of the warning. No, I don't think that I can change the quota on my computer. I understand, that outlook gets the warning from IMAP server and shows it to me. But, I have another computer, with the same mailbox, which shows the said warning once a day, not once a minute. How can it be? 0xFFFF (talk) 18:32, 6 July 2009 (UTC)

Are they both set to check for new mail at the same frequency? The quota warning normally only appears when you attempt to send mail or you move mail from one mailbox to another (this includes anti-spam filters that automatically move mail from you inbox to a junk folder). -- kainaw™ 19:04, 6 July 2009 (UTC)

context free grammar and regular expressions

Is it possible to verify "multiple lines of text" confirms to a defined set of simple context free grammar rules using regex (perl / java) ? CFG, and regular expression wiki pages are confusing. --V4vijayakumar (talk) 12:57, 6 July 2009 (UTC)

No. You cannot capture a (truly) context free grammar by regular expressions. But then, yes, you can use perl/java to build a parser that parses your cfg, which might uses regular expressions for some of the simpler rules. One simple example of a cfg is { S->x; S->(x) } . The language generated contains the letter x enclosed in parentheses, but only if there are exactly a much opening as closing parentheses. This is more than a regexp can do. 93.132.180.226 (talk) 14:51, 6 July 2009 (UTC)

(EC) In theory, no, but in practice, yes. Some languages that can be described by CFG's, such as "all strings that start with some number of as and end with that same number of bs", can not be described by formal regular expressions. That said, they can easily be described by general programming languages with approaches like:

say "matched" if /^(a*)(b*)$/ && length($1) == length($2)

You could also use a parsing framework like yacc or Parse::RecDescent. If you post exactly what you're looking to match you might get some more specific advice. --Sean 14:55, 6 July 2009 (UTC)

It's been a while since I reviewed theory here, but wouldn't these exceptions that have been brought up be "context"? By definition, shouldn't a context-free grammar not need to save state, like "number of as counted last time"? So, in that case, the issues that regular expressions cannot handle are not really a case of failure for "context-free" grammars. I could be incorrect here, this stuff was always mind-boggling to me... Nimur (talk) 15:15, 6 July 2009 (UTC)

Context-free refers to the non-terminal fired, not to some state the recognizing machine has reached. See Context-sensitive grammar. There, you can fire (expand) a non-terminal only if it is preceded and followed by special strings that are part of the rule. 93.132.180.226 (talk) 15:48, 6 July 2009 (UTC)

Ubuntu operating system?

Is is technically correct to say that Ubuntu is an operating system? From a neutral/unbiased point of view of a computer scientist? Or is it Linux (or GNU/Linux or GNU/Linux/X) that is the operating system? SF007 (talk) 16:32, 6 July 2009 (UTC)

Please, avoid ethical/philosophical/political opinions, that is not the point of the question SF007 (talk) 16:33, 6 July 2009 (UTC)

Ubuntu is a distribution (or flavor) of Linux. The key point is that the different distributions use the same operating system. They use different package managers (or use the same one with different versions of the packages). -- kainaw™ 16:36, 6 July 2009 (UTC)

Is the difference between two Linux-based distributions comparable to two different Windows or Mac OS iterations? Put another way, are Gentoo and Ubuntu (or any two Linux distributions) more alike than Windows 95 and Windows 98 (or any two Windows iterations)? — Twas Now ( talk • contribs • e-mail ) 17:54, 6 July 2009 (UTC)

Not at all. An equivalence would be comparing the Linux 2.4 kernel to the Linux 2.6 kernel. A single distribution may contain multiple versions of the kernel. For example, Fedora began with the 2.4 kernel but has adopted the new kernel. So, it comes down to "what is the difference between Ubuntu and Fedora?" They are both using the 2.6 kernel. Most of the optional packages, such as Gnome, KDE, Firefox, Thunderbird, etc... are the same versions on both distributions. The difference is that Fedora uses RPM format packages and Ubuntu uses deb format packages. So, if you want to be technical (which the question is asking for), Ubuntu could be called the "Ubuntu GNU/Linux Operating System". If you say "Ubuntu Operating System", everyone will know that GNU/Linux is implied. -- kainaw™ 19:01, 6 July 2009 (UTC)

It would be correct or incorrect based on one's definition of "operating system". The general public usually thinks of an operating system as the system software and all the stuff that comes with it (so Ubuntu would be one). Computer scientists often think of operating systems as the kernel (computing) only (so Ubuntu would not be one). They are both correct, in given contexts. --Sean 21:35, 6 July 2009 (UTC)

In all technical terms, anything that can handle multiple tasks and provides things like semaphores is an operating system (see things like uC OS). Linux is the operating system of Ubuntu. Ubuntu is Linux running GNU programs. GNU likes to combine both and call it GNU/Linux operating system, because they believe the kernal is useless without the programs. On Windows the GUI is tied to the kernal, not so on GNU/Linux, so its hard to believe GNUs position. It is fair to say Ubuntu is GNU/Linux, but its probably not fair to say Ubuntu is an operating system.--155.144.40.31 (talk) 22:20, 7 July 2009 (UTC)

M4A conversion software

Hi, I had to sing the Thriller on my iPhone and send it to my friend (don't ask). But the file emailed as a M4A and not a MP3. What conversion software let's you convert the two said file types? --32.161.10.116 (talk) 18:29, 6 July 2009 (UTC)

I use this program. It's free. There are probably many others available, too. — Twas Now ( talk • contribs • e-mail ) 19:18, 6 July 2009 (UTC)

question about library programs for solving partial differential equations

On someone elses behalf, please see Wikipedia:Reference_desk/Science#Simulate_semiconductor - question 2.

83.100.250.79 (talk) 21:51, 6 July 2009 (UTC)

gnuplot

Hello,i'm having a question about gnuplot and i was hoping that someone could help me find a solution. I'm trying to make a contour out of some files with gnuplot for a 2-d graph.Although i've read the manual i can;t find the way to do it.Either it expects more data so that it can make a third axe for 3-d plot or it doesn't make contour. —Preceding unsigned comment added by Zzzmith (talk • contribs) 22:21, 6 July 2009 (UTC)

Post some input data and describe what you want the output to look like. --Sean 14:27, 7 July 2009 (UTC)

I want to plot 10 dat files with two coloumns in every file all together in one 2-d plot(x,y)with only one y number to correspond in every x number.One of these files would be for example like this:

0 , 2
0 , 3
1 , 5
2 , 7
2 , 8
3 , 9
4 , 9.5
4 , 10       

etc. So by plotting all the 10 files i want to have 10 different lines in one plot. THAKS FOR YOUR EFFORT —Preceding unsigned comment added by 188.4.16.71 (talk) 18:25, 7 July 2009 (UTC)

Just type/paste in the following (all on one line):

plot "1.data" with lines, "2.data" with lines, "3.data" with lines, "4.data" with lines,
     "5.data" with lines, "6.data" with lines, "7.data" with lines, "8.data" with lines,
     "9.data" with lines, "10.data" with lines

You'll need to first remove the commas from your data files. --Sean 16:00, 8 July 2009 (UTC)

comp

what is the role of o.s in developing the software

Read our article operating system, which will probably help you. Tempshill (talk) 03:26, 7 July 2009 (UTC)

OS means operating system. The article in Wikipedia here may help. --98.154.26.247 (talk) 05:55, 7 July 2009 (UTC)

Adding MP3 durations

I have hundreds of MP3 files, by various artists, and it would be convenient if I could quickly add up the duration of groups of MP3s on the fly, without having to go through them and laboriously add them mentally. But when I highlight a group of songs, right-click, and enter 'Properties', the 'duration' value is 'multiple values', so that doesn't help. I've tried various things, like copying the songs into a separate folder, or selecting them and pressing 'play selection', but I'm just groping in the dark. Does anyone have a solution? LANTZY^TALK 23:09, 6 July 2009 (UTC)

iTunes can do this easily. I expect other music players can too. Algebraist 23:23, 6 July 2009 (UTC)

Using Windows Media Player, you can (temporarily) create a playlist. The total play time of the playlist is displayed at the bottom (or top?) of the list. Astronaut (talk) 13:08, 7 July 2009 (UTC)

On Linux you could do:

mp3info -p '%S\n' song1.mp3 song2.mp3 song3.mp3 | perl -lne '$t += $_; END { print $t }'

--Sean 14:21, 7 July 2009 (UTC)

Thanks, everyone. I figured it out. LANTZY^TALK 17:22, 7 July 2009 (UTC)

BEAV for Windows 98 ?

I'm looking for something like the Binary Editor And Viewer that runs under Linux. I have a 2GB binary file I'd like to view with it. In case you're wondering, the file is an apparently corrupted file cabinet full of my AOL e-mails, which AOL can no longer read. I'd like to be able to view the data in any way possible. Thanks. StuRat (talk) 23:54, 6 July 2009 (UTC)

Comparison_of_hex_editors - maybe someone who knows the program could add a link from BEAV to a description on this page as well?83.100.250.79 (talk) —Preceding undated comment added 00:01, 7 July 2009 (UTC).

Thanks. StuRat (talk) 12:33, 10 July 2009 (UTC)