Wikipedia:Reference desk/Archives/Computing/2008 February 1

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[edit] February 1

[edit] 3.5 floppy

i have successfully saved articles from the wikipedia online reference and now i can't seem to find a way to recall the information from the disk. it shows up on the "my computer" element of the desk top, but i havn't found a way to see it in its entirety. lookin for characters on tool bars or icons in the desk top.63.215.29.80 (talk) 00:15, 1 February 2008 (UTC)

After seeing your questions on the Help Desk and then here, I can only assume that you put a floppy disk in your drive, told AOL to save the page on the floppy, and now you can't find it in the My Computer window. There are many possible problems. First, are you certain that you saved it on the floppy? If you don't select a place to save, AOL likes to put things in some weird place called a file cabinet or something similar. Technically, it is not on your computer at all. It is on AOL's server. Assuming you actually saved it to your computer, did you specifically select the floppy drive? It should be marked as either an A: or B; drive. If not, it is most likely saved either on your Desktop or in your My Documents directory. Assuming you did save it on the floppy without problems, is the floppy any good? Is the drive any good? Floppies are not dependable anymore because they are not in high use. About 5 years ago, I was involved in purchasing floppies for the University I worked at. We purchased them in lots of 10,000. A third of them were completely unusable right out of the box. Another third would fail after a little use. The floppy drives were no better. Half the computers on campus had bad floppy drives. The quality surely has gone down since then. So, let's assume you saved it on the floppy and the floppy works. Is the floppy still in your floppy drive? If not, there is no way your computer will be able to pull up the file. If it is in your drive, what do you see when you click on My Computer and then the A: drive? You should see the file. If you double-click on it, Internet Explorer will attempt to open it and show it to you. It is very likely that it will look funny because it probably didn't save any of the images or style sheets. But, the content of the page should eb visible. If none of that has anything to do with your problem, please explain in detail what the issue is. -- kainaw™ 04:08, 1 February 2008 (UTC)

[edit] Code Question

Could someone please give me the code for the "not equal" sign? (i.e. "=" with a mark through it) Zrs 12 (talk) 01:55, 1 February 2008 (UTC)

Still working on the code, but here's one: ≠ Useight (talk) 02:06, 1 February 2008 (UTC)
Well, in Unicode it's 2260, and in programming languages it's often referred to as <> or !=, but I doubt any of those helped. Useight (talk) 02:12, 1 February 2008 (UTC)
U+2260 in hex equals 8800 in decimal, you could use &#8800; in HTML. List of XML and HTML character entity references shows &ne; also. And Help:Math leads me to \neq for TeX. Any of that helping? --tcsetattr (talk / contribs) 02:19, 1 February 2008 (UTC)

No, thanks though. I need the LaTeX code for it to type a mathematical formula with it here on Wikipedia and the symbol at the bottom of the screen (≠) gives me an error message when I try to use it. Zrs 12 (talk) 02:23, 1 February 2008 (UTC) Oops srry reposted after an edit conflict and didn't see where you gave it in LaTeX. So, yeah, thanks, that's it. Zrs 12 (talk) 02:25, 1 February 2008 (UTC)

[edit] Are the Wikimedia servers still in Florida?

I know Wikimedia mover to California. Did they move the servers? Jet (talk) 07:21, 1 February 2008 (UTC)

No, they're staying at the datacenter in Tampa. --Dapeteばか 16:23, 1 February 2008 (UTC)

[edit] MacBook, Black MacBook, or MacBook Pro

Should I get a MacBook, a Black MacBook, or a MacBook Pro? Jet (talk) 07:32, 1 February 2008 (UTC)

Well what do you want it for? If you just want a cheap laptop that runs OSX then I guess get a MacBook, although you might find the MacBook Air more to your suiting. It isn't out yet though I don't think. If you need a powerful work laptop (that runs OSX) then a Macbook Pro would be what you want. You should know that you can get a laptop that is quite a bit more powerful for the same amount of money a Mac costs, if you don't care about OSX TheGreatZorko (talk) 08:45, 1 February 2008 (UTC)

In fact, The MacBook Air seems to be available now: [1] jeffjon (talk) 14:33, 1 February 2008 (UTC)
Note that even a "regular" MacBook is a pretty powerful machine. I use mine for a wide variety of processor-intensive tasks (virtualization—including virtualization of DirectX games, photo manipulation, video editing, desktop publishing, etc.) and it does them all very, very well. --24.147.69.31 (talk) 16:03, 1 February 2008 (UTC)
The black one is pretty impressive looking but scarcely better than the white macbook (which I have - 2ghz dual core, 1gb ram). The Macbook Pro is nice but personally I think unless you're after a real power-house of a laptop the macbook will do fine. Of course your best bet is to go off and read reviews of each of them to help you make up your mind. With that in mind (http://www.notebookreview.com/), happy hunting ny156uk (talk) 17:10, 1 February 2008 (UTC)

The short answer is ... it depends on what you want it to do. Could you delineate a few main tasks that you want you computer to accomplish? Kushalt 01:12, 2 February 2008 (UTC)

Yes if you want to accomplish editing a home movie while balancing your laptop on the end of your knee and listening to your ipod and eating a p'zone and admiring your designer jeans and staring frantically as your iphone gets hacked from 30 miles away while wondering why apple built in forward-obsolescence so you inexplicably can't boot Leopard through Boot Camp, then buy a mac. If you're really crazy about OS X, then you're really crazy :D\=< (talk) 02:00, 2 February 2008 (UTC)
Right, and then you can think about which of the many flavors of Vista you'd like to get ripped off with so you have essentially a Mac-like GUI layered over Windows XP and wonder why so much of your processor time is devoted to anti-virus and anti-spyware. And then you can wonder why you bought into an operating system that is only seriously updated once a decade, by a company that is about as forward-looking as a rear-view mirror. --24.147.69.31 (talk) 17:55, 2 February 2008 (UTC)
Any half-paralyzed invalid with an opposite half a brain doesn't need antivirus software, and nobody actually buys vista anyway --:D\=< (talk) 18:50, 2 February 2008 (UTC)

Froth, a hundred million mindless zombies have already done so according to New York Times [2]

The most recent version of Windows, released almost exactly a year ago, has already been installed in 100 million computers.

or are they mindless zombies? Kushalt 01:54, 3 February 2008 (UTC)

I mean, I use Apple Mac OS X and I know that they are not invincible. Kushalt 02:01, 3 February 2008 (UTC)

[edit] Embedded images to attachments

Can I make Gmail convert an embedded image in an incoming mail to an attachment, particularly if it can't find where the image is embedded? NeonMerlin 08:16, 1 February 2008 (UTC)

Download mails as POP using the free software, Mozilla Thunderbird? Kushalt 12:11, 1 February 2008 (UTC)

You need to enable POP access in your Gmail settings and then you can use Mozilla Thunderbird to access the email. As far as I know, you cannot download spam with POP (IMAP allows access to spam). If you don't want to spend hours downloading every email since the beginning of time into your computer, IMAP is a good option too. Mozilla Thunderbird supports POP as well as IMAP. (This is original research, I know but it is not an article) Kushalt 02:00, 3 February 2008 (UTC)

[edit] Tape Drives

Hi. I was reading 81.79's 'biggest memory' question, and in the Petabyte article that Algebraist linked to, in the 'Petabytes in use' section it says that CERN has 10 PB of data stored on robotic tape store. I thought tape backups were an old, slow, unreliable technology and generally no longer used. Or, is this kind of tape store different to the one I'm thinking of? -JoeTalkWork 08:28, 1 February 2008 (UTC)

Tape is still used as one of the more common backup medias, actually. Mostly for the reason that per megabyte it works out quite a lot cheaper than hard drives, and can be more compact. The fact that it is slow to access doesn't really matter when being used for backup purposes.

See the article on Magnetic tape data storage TheGreatZorko (talk) 08:41, 1 February 2008 (UTC)

Tape also allows for inexpensive off-site, fire-safe storage. There's an old joke in computing:
Q: What data transport method has the highest aggregate data transmission bandwidth?
A: An 18-wheeler full of magtapes!
Atlant (talk) 13:02, 1 February 2008 (UTC)
Is this joke actually true? If so, in what sense - What is it that we are measuring? Is it \frac{Data \cdot Distance}{Cost}? Would a cargo ship be more effective? -- Meni Rosenfeld (talk) 13:38, 1 February 2008 (UTC)
If one ignored the time spent creating and reading the magtapes and merely considered how long it took the truck to move (in the good old days) a terabyte of data from, say, Boston to Waltham, the joke certainly could have been construed as "true". Nowadays, when a truck probably holds a petabyte of data easily, it's probably still true in the same limited contexts as originally.
Atlant (talk) 15:07, 1 February 2008 (UTC)
I've heard similar jokes. We IT guys are a laugh riot! But anyway, cost isn't usually a factor in bandwidth calculations. --LarryMac | Talk 14:15, 1 February 2008 (UTC)
Hm? Surely with unbounded resources you can get virtually unbounded bandwidth? -- Meni Rosenfeld (talk) 14:18, 1 February 2008 (UTC)
Well yes, of course, but that's the point of measuring bandwidth - the resources are not unbounded. Of course the strict definition of bandwidth is all about analog frequencies and such, but as most commonly used, it is a measure of capacity. cf. flow rate. Still, cost does not play a part. --LarryMac | Talk 15:05, 1 February 2008 (UTC)
Did they mean 'resources=memory capacity' or 'resources=money' here. And shouldn't that last sentence read 'cost is a major factor'?87.102.12.64 (talk) 15:25, 1 February 2008 (UTC) Oh hang on I've got a cold - understood first joke though - wheelbarrow of SD cards. Ignore me.87.102.12.64 (talk) 15:27, 1 February 2008 (UTC)

The latency (engineering) makes the cargo ship ineffective. Kushalt 16:45, 1 February 2008 (UTC)

The version I always heard was "Never underestimate the bandwidth of a station wagon full of tapes". Which is sourced here: q:Andrew S. Tanenbaum --tcsetattr (talk / contribs) 21:31, 1 February 2008 (UTC)
Sound superior to IP over Avian Carriers. --— Gadget850 (Ed) talk - 21:56, 1 February 2008 (UTC)

Thanks guys, that was all very useful and interesting! --JoeTalkWork 09:18, 4 February 2008 (UTC)

[edit] Early computer displays

Why were green monochrome displays used in the 1970s and 1980s? Was to due to its supposed improved reading visibility? —Preceding unsigned comment added by 60.242.27.213 (talk) 10:34, 1 February 2008 (UTC)

Cathode ray tube says:
An oscilloscope trace can be any color without loss of information, so a phosphor with maximum effective luminosity is usually used. The eye is most sensitive to green: for visual and general-purpose use the P31 phosphor gives a visually bright trace, and also photographs well and is reasonably resistant to burning by the electron beam. For displays meant to be photographed rather than viewed, the blue trace of P11 phosphor gives higher photographic brightness; for extremely slow displays, very-long-persistence phosphors such as P7, which produce a blue trace followed by a longer-lasting amber or yellow afterimage, are used.
-- Finlay McWalter | Talk 11:45, 1 February 2008 (UTC)
There were multiple driving forces. Vector graphics systems were green for the reasons cited above. When raster-scanned character cell terminals arrived on the scene, I'm not sure why IBM settled on green for their ubiquitous 3270 terminals, but the reasons cited above are still reasonable and maybe it was just market expectations from the vector-scanned days. Digital Equipment Corporation, on the other hand, used cheap television monitors for their VT05 that, by default, had P4 (white) phosphors. Later, European health-and-safety regulations led to a lot of terminals with amber phosphors. but these were actually terrible screens; images "burned in" to the amber phosphor very easily. And after that, full-color terminals became very affordable so the whole thing became a "user preference" item.
Atlant (talk) 12:59, 1 February 2008 (UTC)

[edit] Customized context menu search

In Firefox, if I select text and right-click, I get the option to search for that text using whatever search engine is active in the upper-right-corner search menu. I search frequently with Google, Wikipedia, and WordReference. Is there a way to directly add all those links to the context menu? I've found this: [3] which, is pretty good, but it would be even better if I could directly place all those options in the root menu instead of selecting from a second-level menu each time. Thanks, jeffjon (talk) 14:30, 1 February 2008 (UTC)

SearchWith was suggested to me in a similar situation just over at the RefDesk a few weeks back. I recommend it, even though it too operates from the second level. But it does its job fine. Cheers, Ouro (blah blah) 15:20, 1 February 2008 (UTC)

[edit] Links

In Wikipedia, how would one provide a link to a specific part of another page and not just to the heading of another page? Zrs 12 (talk) 15:04, 1 February 2008 (UTC)

You can link to a section using #. For example, I can link to this question using [[Wikipedia:Reference desk/Computing#Links]]. -- kainaw™ 15:08, 1 February 2008 (UTC)
You can also link to things that aren't section titles. To do this, add {{anchor|anchor name}} to the target page in the desired place and link with [[Target page#anchor name]]. 131.111.8.104 (talk) 17:37, 1 February 2008 (UTC)

[edit] weird behavior of fsquirt.exe

Windows XP SP2 has a program %SystemRoot%\System32\fsquirt.exe which can send and receive files via Bluetooth. This program is acting weird:

  • When called from "SendTo", it receives the file being sent as a commandline parameter, and you just have to select the device. But when called as fsquirt file.txt it doesn't detect it.
  • When you drag a file on fsquirt.exe, it again offers to send the file, and you just click "Next". But when I rename it into, say, Bluetooth.exe, it won't work this way.

All these ways will pass the filename to the .exe, as fsquirt.exe C:\autoexec.bat

  • Drag C:\autoexec.bat over fsquirt.exe = "Send autoexec.bat"
  • Drag C:\autoexec.bat over fsquirt.exe renamed to anything.exe = "Welcome to Bluetooth File Transfer Wizard"
  • Call fsquirt.exe from SendTo = "Send autoexec.bat"
  • Type fsquirt.exe C:\autoexec.bat = "Welcome to Bluetooth File Transfer Wizard"

but they all should work the same way (you can test with a program that prints all commandline parameters). Why is that so? --grawity talk / PGP 18:37, 1 February 2008 (UTC)

Trying to get Windows to be consistent is a road to madness. The renaming thing suggests that there's some code in Windows somewhere that says:
if (filename == "fsquirt.exe")
  treat_it_specially();
else
  treat_it_in_the_usual_way();
You could probably create a small executable called "fsquirt.exe" that just prints its arguments and watch it in action. --Sean 22:06, 1 February 2008 (UTC)
Okay, I did one with Multimedia Builder ($me->skills['c++'] == 0;), and here are the results:
  • Command line, fsquirt.exe file => my app opens, says file
  • I drag a file over my new fsquirt => ..."Send file over Bluetooth" opens :?
  • I even tried renaming putty-0.60-installer.exe to fsquirt.exe and even it does the same.
When I drag something over my new %userprofile%\Desktop\fsquirt.exe, SysInternals' Process Explorer shows this windowsism (screenshot).
--grawity talk / PGP 15:27, 2 February 2008 (UTC)
Another screenshot: [4] —Preceding unsigned comment added by Grawity (talk • contribs) 15:41, 2 February 2008 (UTC)

[edit] Buying a video card

I'm in the market to buy a new video card. What do you guys think of this or this? Other ideas? I've got a buget of up to $300. What's the best card I can get? Useight (talk) 21:36, 1 February 2008 (UTC)

Traditionally, ATI cards do not behave quite nice with GNU/Linux or other free operating systems. I am not sure about this particular ATI card. I also have no idea on how ATI has changed since AMD bought it as AMD at least tries to be free software friendly. Kushalt 22:40, 1 February 2008 (UTC)

I'm using Windowx XP. Useight (talk) 22:47, 1 February 2008 (UTC)
Since you have Windows XP, just purchase the most recent ATI or nVidia card you can afford. You only notice video card deficiencies when playing games that are ridiculously graphics intensive. Cards for those games are more expensive than $300. My last video card was $580. So, either get the most recent version for $300 or keep saving for the latest and greatest model for around $600. -- kainaw™ 22:55, 1 February 2008 (UTC)
I would like to play Crysis on high on 1024x768 resolution. If you spent $580, you must have gotten the 8800GTX or something similar. Do you think an 8800GT would let me play Crysis on high settings? I have an FX-60 2.6GHz and 3GB DDR. Useight (talk) 23:50, 1 February 2008 (UTC)
The 8800GT you pointed out earlier will easily run Crysis at high on the settings you want. You could probably run Very High if you were under Vista TheGreatZorko (talk) 12:36, 6 February 2008 (UTC)
The 8800 is merely the recommended card. That implies to me that the developers had their hands on 9800 cards for development. It isn't abnormal for ATI and nVidia to give developers experimental cards so the games can be developed beyond the specs of what is commercially available. -- kainaw™ 01:07, 2 February 2008 (UTC)
If you have a named brand computer (like Dell or HP or something) its wise to check that the card will actually work in your computer before buying.--TreeSmiler (talk) 01:35, 2 February 2008 (UTC)
I built my own computer (computers are really the only thing I know a lot about, so that's why I'm answering questions here a lot), but I just wanted a second opinion before replacing my old GeForce 6800GS. I think I will go with this XFX 8800GT unless I can find one that has more factory overclocking. Useight (talk) 02:49, 2 February 2008 (UTC)

[edit] C++ versus Java

Hi:

Is it just me or do some of you also feel that Java is much cleaner and more consistent than C++ (efficiency aside)?

129.97.252.233 (talk) 22:32, 1 February 2008 (UTC)

I prefer C++, actually, at least for procedural-based programming (as opposed to object-oriented). Useight (talk) 22:46, 1 February 2008 (UTC)
Java is usually "cleaner" and "more consistent" in that there is one and only one official Java parser/compiler. There are many C++ parser/compilers. Therefore, you run into instances where sometimes main must return void. Sometimes it must return an int. Sometimes you have bool defined. Sometimes you don't. If all of your work is written for one and only one C++ parser/compiler, then you will have clean and consistent code. Also, as a side note, you don't have to know anything about reserving and freeing memory in Java. It attempts to do it for you. By removing all that code, you end up with cleaner looking code. In the end, it is a matter of opinion. If you have a high affinity for parenthesis, Lisp may be the cleanest and most consistent code in the world for you. -- kainaw™ 22:50, 1 February 2008 (UTC)
The presence of an "official" compiler and interpreter completely discredits java in my opinion as a legitimate programming language. The only reason Sun bothered to create a java specification is so they could call their little javac/java lemonparty a Computer Language. Now that it's been actually formalized, thoretically there should be fully open-source compilers and interpreters competing with the official implementation, but there really aren't. And the official implementation is only recently open-source, and it's not entirely open- Sun refuses to allow third parties access to their mind-boggling deep-magic-at-the-foundations-of-the-universe computer science turing theory..... stuff. Didn't this come up a couple months ago? Well, if nobody can find the link just know that it was so impressive I was on my knees facing the Sun. But it's not open, which makes java just stupid --:D\=< (talk) 01:43, 2 February 2008 (UTC)
Oh, and certain things in C++ are up to the implementation to decide how to handle, but usually that's just how to handle bad code, and if you follow the official specification your code should compile on any specification-compliant compiler --:D\=< (talk) 01:45, 2 February 2008 (UTC)
Java is much cleaner and more consistent than C++, because they have very different design goals. One of Java's was to be clean and consistent, while one of C++'s was to be backwards-compatible with C. Those two things are pretty much incompatible goals. --Sean 17:31, 2 February 2008 (UTC)

"Java is usually "cleaner" and "more consistent" in that there is one and only one official Java parser/compiler.". There are actually a number of different compilers, virtual machines, and class libraries out there. I use IBM's at work, for instance. 81.187.153.189 (talk) 00:17, 7 February 2008 (UTC)

[edit] Computer performance improvement with more memory

I have a Dell Dimension 2400 with 512 MB RAM. If I put in another 512 MB, what improvement in performance would i notice?--TreeSmiler (talk) 23:02, 1 February 2008 (UTC)

Having only 512MB RAM isn't good at all. You'll see noticeable differences in upgrading to 1GB if you're running Windows XP. Boot time should be quicker and game loading time should be better as well. The 2400 is a pretty old computer, so I'd actually recommend getting a newer one if budget allows. Useight (talk) 23:53, 1 February 2008 (UTC)
Extra memory will usually result in improvement. When you don't have enough memory, your hard drive is used. If you have a hard drive light, you'll it blinking all the time. Since it takes far less time to access memory than a hard drive, you get better performance with more memory. If, on the other hand, your hard drive light hardly ever blinks, you won't see much improvement as everything is already being done in the memory you have. With only 512MB, I would expect your hard drive to be doing a lot of overtime. -- kainaw™ 01:03, 2 February 2008 (UTC)
My mother had a very similar computer and I upgraded her to 1GB of memory last winter. Among her most immediate improvements were that the computer started up much faster, programs were much quicker to launch, and she no longer got virtual memory notices. Big improvements all around for not a whole lot of cash. --24.147.69.31 (talk) 01:37, 2 February 2008 (UTC)
Interesting. I have a slow startup problem --TreeSmiler (talk) 01:55, 2 February 2008 (UTC)

If you have Windows XP, you have already met the minimum recommended requirement with 512 MB. Before upgrading, it is advisable that you try to determine the cause of the slow startup. Do you have any application autoloading but you don't want it to? Do you have too many fonts that you don't use? Do you think you could disable some system services? Kushalt 15:24, 2 February 2008 (UTC) A little reminder: Please back up unreplaceable data before doing anything that is potentially irreversible.