Wikipedia:Reference desk/Archives/Computing/2006 September 27

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On Intelligence

Has anyone read this? If so, what do you think of it? Have you tried out any of its ideas? Black Carrot 06:55, 27 September 2006 (UTC)

You'd probably be better off asking this question on the science desk. — QuantumEleven 07:47, 27 September 2006 (UTC)

I could, but people get pissy when you double-post, and I'm really more interested in whether something like that could be usefully implemented on a PC than whether it's how our brain works. There's a lot I don't get, and it's entirely to do with the data structure he's proposing. Besides, I can just ask my mom about the brain part. If you've read it (and understood it), I'd appreciate comments, starting with "He's a visionary" v "He's stupid/insane/lying". Black Carrot 14:23, 27 September 2006 (UTC)

Visionary's and Insane People are the same. the thread that divides those two words is called history(most of the visionary's of now were called insane in the past)Graendal 06:33, 28 September 2006 (UTC)

Informative indeed. I was hoping for something more specific, though. For instance, has anyone here worked in AI, especially on neural nets? If so, would what he's suggesting actually be able to train itself properly? I know that's one of the big problems with large, complex nets that don't use backpropagation. Would it actually be able to better model patterns than a normal net, or is it essentially equivalent? And how does it adjust weights? He doesn't really mention that. Black Carrot 00:53, 29 September 2006 (UTC)

software

41.220.14.7 10:37, 27 September 2006 (UTC)can i be able to get software of any type to help me in my field of computing? DAVID

Yes, you can. And, if you wish to tell us what type of software you're looking for, we may even be able to help you find it. StuRat 11:48, 27 September 2006 (UTC)

Perhaps. --Proficient 03:56, 30 September 2006 (UTC)

ＤＶＤ

What's the deal with the Unicode characters ＤＶＤ, and what purpose do they serve? They're definitely not the ASCII letters DVD, because (a) in some fonts, they're shorter and/or wider-spaced, and (b) unlike DVD, they return no results in a search of Wikipedia (although both get the same Google results). They came in a piece of Japanese spam. (Why I'd be getting Japanese spam, I don't know.) NeonMerlin 10:57, 27 September 2006 (UTC)

These are unicode characters FF24 and FF36, which are named "FULLWIDTH LATIN CAPITAL LETTER D" and "FULLWIDTH LATIN CAPITAL LETTER V" (along with the rest of the alphabet, and lowercase "fullwidth" characters at nearby codes[1].) Quite why the Unicode Consortium decided to put them in, I don't know, but that's what they are. Your spammer was proably using them to try to get round filters which only know about ASCII. And as for why you're getting Japanese spam, well, a Japanese spammer has probably picked up your email address, and doesn't care in the slightest that you're never going to buy anything from them. -- AJR | Talk 12:23, 27 September 2006 (UTC)

Might they be used as Roman numerals? Sum0 22:36, 28 September 2006 (UTC)

No, IIRC they exist for round-trip compatibility with legacy character encodings. --cesarb 15:45, 29 September 2006 (UTC)

Though I don't know what their original purpose was, they're useful for aligning Chinese text, since all Chinese characters are written fixed-width.  freshofftheufoΓΛĿЌ  16:25, 1 October 2006 (UTC)

Homemade Media Centre Extender?

I've got a Media PC with Windows MCE installed on it, running my TV/PVR. I also have a spare computer around that I would like to use as a Windows Media Center Extender, to let me watch stuff on a second TV. I've tried just using Remote Desktop to connect it in (using the multi-session hack), but Media Center doesn't allow the playing of video over a Remote Desktop connection. Is there anyway around this, to make the spare computer act as an Extender (instead of buying the extra Extender hardware) and connect in that way, so that it could play the video? --Maelwys 11:48, 27 September 2006 (UTC)

I'm not familar with Windows MCE but it can share files like regular Windows XP, yes? If that's the case, you could mount those files as a network drive on your other computer. From there you should be able to play the files off that computer. —Mitaphane _talk 02:04, 29 September 2006 (UTC)

Mitaphane is correct. Simply share the files and Windows Media Player can play them on your second computer. For your reference the files are located in <local system drive>\Documents and Settings\Public\Recorded TV on Windows XP systems and in <local system drive>\Users\Public\Recorded TV on Windows Vista. For those who do not know how, you do not really need to mount a drive for them. You can simply browse to them through the network neighborhood.

world town and city distances

I want to obtain software so that i can determine the distances between all cities and towns around the world please but cannot find it. Can you please advise. It would be the same as on some dating sites where they tell your possible date how far they are away from you in miles etc. Please could you advise me on <email address removed>. Many thanks, Evan Williams

Remember to not include your e-mail address (as stated at the top of the page). What you're looking for is a great-circle distance calculator, and possibly a table of geographical coordinates for various cities. You can find many free online instances of the first from the article, and the second is satisfied by Wikipedia's appropriate municipal articles. Anything else? --Tardis 14:19, 27 September 2006 (UTC)

Google Earth might be a user friendly way to do it. It includes a ruler (measures direct distance), as well as a directions thingamabobber. -- Consumed Crustacean (talk) 03:00, 29 September 2006 (UTC)

Computer Temperature

What would be a safe temperature to let a computer run at? I've noticed that a lot of motherboards which are able to regulate fan speed according to temperature tend to have as a default keeping temperature around 50 degrees centigrade. My machine is almost always around the high 30s and I'm interested in reducing noise overnight occassionally and if I trust these defaults it seems to suggest I could lower the fan speed enough to raise temperature 10 degrees or so and it should still be safe. --Kiltman67

My computer is very quiet at night because I turn it off. --Kainaw ^(talk) 15:54, 27 September 2006 (UTC)

Depends on what model of CPU you've got, and what part of the computer you're talking about. With my computer (late-model Athlon XP) I try to keep the CPU below 70C, the northbridge below 40C, and the hard drives and general case temperature below 35C. The CPU can safely be run at temperatures up to the point where it starts crashing or giving bad results (it will crash before temperatures reach the danger zone), but doing so can reduce the life expectancy somewhat -- instead of failing after ten years, it might fail after eight. --Serie 19:37, 27 September 2006 (UTC)

My CPU is an Intel Core 2 Duo E6300. Intel quote a thermal specification of 61.4 C but I don't know exactly how this should be taken: whether I should take that as a maximum safe operating temperature or merely the limit of what the processor can take. --Kiltman67 19:47, 27 September 2006 (UTC)

Intel chips have a circuit that slows the CPU down as it starts to get too hot. The limit of 61.4C is probably the point at which this kicks in, so running the computer at 50C overnight won't be a problem. --Serie 20:38, 29 September 2006 (UTC)

Another way of reducing noise is to get a quieter CPU cooler. I bought a Zalman heat-sink/fan and now the noisiest thing in my computer is the hard drive. - Rainwarrior 07:23, 28 September 2006 (UTC)

Which version of Linux is easiest for newbies?

I have an old computer which I no longer use but is still resonably powerful (1GHz CPU & 512MB RAM) so rather than let it rot in a cupboard I thought I might install Linux on it and get it running again. But my question is: which version should I use? I know this depends on what you want from Linux, but essentially I want something that feels a bit like Windows (simply because that's what I'm familiar with) and which doesn't require me to invest a huge amount of time into getting it installed and running, as I'm currently studying for the final year of a degree course. Is there a "mainstream" version of Linux that Average Joe (me) can use as a replacement for Windows. --Ukdan999 16:35, 27 September 2006 (UTC)

Ubuntu seems to be consdidered the best distro for those new to Linux. You download the ISO, burn it to a CD and then boot from the CD. During the boot process it does a scan of your hardware and configures itself as necessary. You can choose to install it from the CD as well, but you don't have to. --LarryMac 16:40, 27 September 2006 (UTC)

Thanks, I've decided to go with Ubuntu and am currently downloading it. I just need to know what I have to do to get my PC ready installation. It currently has Windows ME and a trial version of XP sitting on it, but I don't want to keep them. Should I format the PC entirely or just "uninstall" them, or what? And is formatting the hard disk done through Windows/DOS/Other? --Ukdan999 20:17, 27 September 2006 (UTC)

Check this page, in particular the "Select A Disk" section. You can have the installer format your disk, which will effectively uninstall ME and XP. --LarryMac 21:34, 27 September 2006 (UTC)

I disagree, SuSE is the premiere "windows look alike" and KDE would probably make the job of getting used to linux a little easier than gnome, which kind of takes for granted the *nix directory structure (usr, bin, etc, etc ;p). However suse does a little too good of a job of it- it's a 6 cd install, though you do get a LOT of packages. Ubuntu seems a little more stable though. Eh I guess you made a good choice but maybe you would have been happier with suse. --froth^{T C} 03:37, 28 September 2006 (UTC)

I agree with the previous post, I run opensuse 10.1 on both of my desktops here, my parents seem to be getting used to it very fast and they really dont give a damn about technical stuff. There is also an excellent tool called YaST which is like control panel, only a million times better. For one the software management tool gives you access to thousands of apps and you can use add-on repositories for even more cool stuff, so the searching, download, install and configure is all done for you with a mouse click! Finally, if you have broadband, dont waste your time downloading all the CD isos, just download the boot CD and install via FTP from a local mirror, that way you only download what you need (my default install downloaded only 900mb of data, but would have needed most of the CD's to get my packages!). www.opensuse.org is the place to go. There are many other interesting distro's to play with though, one example is www.linuxfromscratch.org which teaches you how to custom build your own linux distro from the ground up, tweaking everything for you machine, it takes hours (if not days) but teaches you lots about unix in the process, it's worth doing if only as a learning excercise. Regards Phill (phillip.upson@hotmail.co.uk)

Converting an AVI file

I have a movie in the AVI format , i.e ".avi" . Windows Media Player is encountering a problem in playing this file, mentioning something about a Codec. Could anyone pl help me in suggesting a suitable codec and how to use it also ??? Thank you a lot.

User : Sanchit

Download VLC Video Player, more than likely it will play your file. --Kiltman67 17:15, 27 September 2006 (UTC)

Hi....i also encountered a similar problem as you sanchit. try downloading D-i-v-X AV Codec Pack from: http://www.download.com/AV-Codec-Pack/3000-2194_4-10509746.html?tag=lst-0-1 after the download just try playing your AVI file.hope this helps you

I wouldn't advise this. According to one "user review", this codec pack has some integrated adware/spyware nonsense (most seem to). Codec packs often have compatiblity issues anyways. Go with VLC, or find out which codec you need by using a tool like GSpot. -- Consumed Crustacean (talk) 22:05, 27 September 2006 (UTC)

Chances are it's xvid or divx, locate binaries for each and install them, then windows media player should play it fine --froth^{T C} 03:38, 28 September 2006 (UTC)

NEVER, NEVER, NEVER download codec packs, chances are you have no idea what they have bundled in them, including possible replacements for the default mpeg and avi encoders on your system, which can harm the stability and or security of your PC. If you need to install extra codecs, do them one at a time, www.doom9.net is a good place to learn about video files. Finally, you seem unsure in your question, a codec is a COmpressor/DECompressor. Computers can only play video as uncompressed AVI (about 1.5GB per hour of video) so most of us compress these into smaller forms, such as MPEG, divx, xvid etc.. The job of the codec is to decompress the video file back to a normal AVI (Audio Visual Interleave in case you wondered) so your computer can understand it. Audio works in the same way, WAV being the only true audio format and all others being compressed forms of it, such as MP3 files. Phill (email removed)

Thank you so much for your help, guys!

Internet sharing problems

My household just got high speed internet last week, and my computer shares the internet with the main computer. However the problem is that my internet connection to it doesn't always work properly. When it isn't working right I can get on web sites fine like Wikipedia and such (albeit a lil slower) but I cannot play games online or do downloading or even go on MSN Messenger. Take last night it was working for me fine, but when i turned it on this morning it was back not working and i haven't been able to get it working properly. It sometimes starts working fine, but it never stops working after it's been working when i keep the computer on. It always seems to work fine on the main computer. Now my question is where is the problem? Any help on this would be greatly appreciated. Croat Canuck Go Jays Go 17:34, 27 September 2006 (UTC)

How are the computers sharing the connection? Through a seperate router or something else? --Kiltman67 19:07, 27 September 2006 (UTC)

Well we have a router in between our computers, sorry I forgot to mention that. Croat Canuck Go Jays Go 19:59, 27 September 2006 (UTC)

Since some things are working and other things aren't might be worth checking the firewall settings on the router, in particular port forwarding. When I was using DHCP on my router I used to notice I'd have problems with MSN if I wasn't given the IP Address the port for MSN was opened for. --Kiltman67 20:30, 27 September 2006 (UTC)

Well i wasn't able to find the port forwarding part on the firewall (unless i have to do it from the main computer), but another thing I found is that the problem doesn't arrive if when I turn off the computer I keep the power bar on. However i usually turn the power bar off because otherwise my mouse stays on and illuminates the whole room, which is kinda annoying. Croat Canuck Go Leafs Go 22:17, 27 September 2006

If the only thing keeping you from having the power bar on 24/7 is the light on the mouse you could always cover it with a box or piece of fabric at night. --Kiltman67 01:02, 28 September 2006 (UTC)

Are there only two computers? What makes one the 'main' computer? Is it running an internet connection sharing tool? When you say there is a router between your computers do you mean both computers connect to that to receive their internet connection? Also, if you want your mouse light to go away power off your computer with the main switch on the back (if it has one). If you can't get the internet to work right ask a computer savvy friend to take a look at the setup, it's probably just a layout problem. --Jmeden2000 20:22, 28 September 2006 (UTC)

MS Access

I am using a to_char and to_number function in sql. To make sure that my query runs successfully I created a mirror database in MS Access and I am trying that query there. But MS Access does not recognize to_cahr and to_number. Can anyone tell me what is the eqvivalent functions for to_char and to_number in MS Access?

I don't see these functions in the MS Jet SQL reference. You may want to install a copy of MSDE or SQL 2005 Express to test queries for SQL Server. --24.159.108.105 03:47, 28 September 2006 (UTC)

MS Access uses Visual Basic functions for data type conversions like this, so you'd use "Str$(number)" to convert a number to a string, and "Val(string)" to convert a string to a number. --Canley 06:43, 28 September 2006 (UTC)

Blu-ray and HD-DVD

What's the point of massive Blu-ray or HD-DVD discs? I was under the impression that XViD/DivX/H.264 could easily fit a 1080p movie on a normal single or double layered DVD, the previously mentioned formats certainly seem to work wonders with standard-resolution movies. Also, H.264 is part of the Blu-ray/HD-DVD standard anyway, so why the excessive bitrates? This would only increase the cost of Blu-ray/HD-DVD equipment. --Frenchman113 on wheels! 19:27, 27 September 2006 (UTC)

I found somewhere that .21 bits per pixel is a good measure for good quality xvid. If you take the number of pixels per frame, 1920 * 1080, multiply it by the numer of frames per second (25 for europeans), and multiply that by 60 * 120 (for a two hour movie), you get the number of pixels in the movie. Multiplying that by .21 gets a rough number of bits for a good quality HD xvid encode. Divide that by 8 to get to bytes and three times by 1024 to get to kilobytes, megabytes and gigabytes respectively. I come out at about nine gigabytes, which is half a gigabyte larger than the capacity of a double layer DVD. Ofcourse h.624 will compress better than xvid, but add a 5-channel high quality soundtrack to the mix, and the fact that DVD's should (emphasis on should) feature a quality that is better than just good, it's clear that regular DVD's don't measure up.

The main thing, however is that it's not so much a question of necessity as of possibility. The reason that HD-DVD/Bluray is coming out is not that we need them foor our HD foootage, but rather that we can produce them at a decent cost. 25 GB is the next generation in optical storage. After that come the possibilities, which include not only HD movies, but also games with a greater detail in texture and personal data storage needs. The whole thought process starts with the capacity of the disks, and from that flow the ideas of what to do with them.

Of course, there's also the Holographic Versatile Disc, which comes out before the HD-DVD/Bluray, and has a capacity four times that of a bluray disc. Depending on the price of the first hardware, it might negate the whole next gen DVD wars. risk 22:14, 27 September 2006 (UTC)

AFAIK licensing costs for MPEG4 and h.264 may have been high. In any case, I guess the studios already have the appropriate systems and so would prefer to stick with MPEG2 for now. Finally, the studios would probably prefer their HD content to be larger rather then smaller to slow down P2P (obviously you may be able to recompress it but that's an extra step) and bluray/HD-DVD burners and media are going to cost a lot more for a long time. We can also assume it'll take a while for the professional pirates in Asia start to get in to the habit. On that note, the studios would have less of an excuse to add all their junk anti-choice (aka anti-piracy) measures if they were justing using DVDs. Nil Einne 00:10, 28 September 2006 (UTC)

Why don't movie companies just compress the video? ... mpeg2 is practically lossless, and it offers only a tiny fraction of the compression offered by even a high-quality double pass xvid compress --froth^{T C} 23:34, 28 September 2006 (UTC)

I think that's the point that the original poster was asking. I have no idea. Last I heard, it was something to do with the movie studios' video encoding tools not having a mature MPEG4 (h.264 ?) implementation yet. I don't know why they wouldn't, as the format has been around for awhile and is supposed to be supported by both HD-disc players. -- Consumed Crustacean (talk) 23:38, 28 September 2006 (UTC)

Bigger font for firefox

Can anybody tell me how to make the font in firefox big by default? I know how to change it in a given window, but I want all of my tabs to be in a large font by default.

If you click on the Tools menu at the top and select Options then click the Content tab, I beleive its in there --Ukdan999 20:20, 27 September 2006 (UTC)

That's only the "default font" --froth^{T C} 03:33, 28 September 2006 (UTC)

Isn't that exactly what the OP wanted to change? It works as expected for me. —da Pete (ばか) 08:41, 28 September 2006 (UTC)

View>Texts size>Increase. Or hold down control and scroll the middle mouse button.

Or do ^+ (hold down control and press plus - the one in the numeric keypad is conveniently located and nice and big). But you'd have to do that for every window you open and the steps are too big to my liking. Then again, the same goes for altering the default font (which, by the way, is at edit > preferences > content in my version of Firefox). Of course you could also change the resolution of your monitor, but that would make everything bigger. DirkvdM 08:44, 30 September 2006 (UTC)

Displaying Hidden Documents

I have a Windows machine. How do I get it to not display hidden documents when I go to Start>Documents? --Yanwen 20:53, 27 September 2006 (UTC)

go to control panel>folder options>View(tab)>choose Do not show hidden files or folders [2]

I already did that. But when you click Start and go to Documents, it still shows hidden files. --24.107.18.155 21:33, 27 September 2006 (UTC) Ops. forgot to sign in. --Yanwen 22:01, 27 September 2006 (UTC)

You mean the recent documents list? I don't think there is a way to do this. You can disable it altogether (right click on the task bar, click properties, start menu, customize, advanced, and uncheck the thing at the bottom). -- Consumed Crustacean (talk) 22:08, 27 September 2006 (UTC)

ActiveX

When I go to certain web pages, a pop up comes up asking me if i want to run an ActiveX control. Is there a way I can stop this from coming up every time.

207.200.116.65 23:12, 27 September 2006 (UTC)

Check your securtiy levels from options--RedStaR 23:59, 27 September 2006 (UTC)

Use firefox or links --froth^{T C} 03:23, 28 September 2006 (UTC)

Before turning off the message it is important to think about why the message is appearing. There are some nasty people in the world who write ActiveX controls that do things you really do not want to happen. Snooping on your web browser, keeping a list of on-line banking passwords you use and sending them back to the author is an example. Slyly adding links into other people's web pages you read that direct you to the author's business is another. Harvesting all the e-mail addresses in your e-mail program and sending them to a spamhouse is yet another. I prefer to leave the warnings on and choose whether or not I trust each web domain to have well behaved ActiveX controls as needed. The alternative can be far more inconvenient in the long run. --Dave 07:52, 7 October 2006 (UTC)

C++ code

Can someone write me a basic geometry calculator using C++ or any suggestions would be helpful. thanks

well you're going to want to include math.h ... --froth^{T C} 03:29, 28 September 2006 (UTC)

Include <cmath>, not <math.h> (math.h is a deprecated C header). But, the question posed is rather vague. If you want to do any of the standard functions, yeah, cmath has stuff like cos and sin and whatever (in radians). You'll probably want to use "double" for your numbers, as they're as accurate as you'll get without getting complicated.

Are you wanting to be able to type in an expression like "5.0 + cos(3.028) * 40.2" and have your program evaluate it? Or do you just want to do calculations? (And isn't there a free calculator program already written that you can use?) - Rainwarrior 03:46, 28 September 2006 (UTC)

Or maybe it's homework :) --froth^{T C} 21:21, 28 September 2006 (UTC)