Wikipedia:Reference desk/Archives/Computing/2006 September 24

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How does SMS to 466453 work?

Does anyone know how an SMS to 466453 ("Google SMS") work? I've read various things, and most just say that shortcodes are service-provider implemented, and that there's a shortcode database that manages stuff like this. But really, how does the message get routed? Does it go through an email gateway, then to Google, and back? Jdstroy 06:23, 24 September 2006 (UTC)

Big Screen, slow Computer

Hi! I plan to buy a 20 inch TFT screen. I´m using a eight year old Pentium II computer with a Riva 128 graphics card (without DVI connector) running Linux (Debian Etch). Can a computer be too slow for a big screen? Will the operating system and the graphics card be able to facilitate a 1400x1050 or 1600x1200 (SyncMaster 203B or 204B) resolution? Thanks in advance, Michael --208.101.59.30 07:39, 24 September 2006 (UTC)

From the RIVA 128 article I see that it supports up to 4MB of memory (the ZX version supports 8MB). I can confidently say that it will not be able to reach such resolutions. ----龙★Ukdragon37★翔^talk 16:34, 24 September 2006 (UTC)

Thank You! I´ve got the 8MB version. If I multiply the resolution with the color depth, I get: 1600 x 1200 x 24bit = 5.5MB. Does this mean it will work? If not, how much do I need? --208.101.59.30 17:04, 24 September 2006 (UTC)

Well, there are other things to taken into consideration such as refresh rates as well. Fortunately, I shall take back my former statement. The NVIDIA press release for RIVA 128ZX[1] says "up to 1600x1200x32bpp @ 85Hz" which sounds rather like the extremes of what this card can do. Of course, don't expect to play games on it! To be on the safe side, I recommend buying a slightly better card, for example a TNT2 or GeForce 256 with at least 16MB as they cost peanuts nowadays. Of course, beware of AGP incompatibilities. Hope this helps! ---龙★Ukdragon37★翔^talk 18:29, 24 September 2006 (UTC)

Thank you very much for your advice, Ukdragon! --208.101.59.30 14:42, 26 September 2006 (UTC) Michael

programming in python

Hello, I have been trying to write a programme in python to mark a sudoku already solved by a play.I must confess that it has not been easy. Please could you just give me a clue? Thanks 196.21.78.18 12:19, 24 September 2006 (UTC)Margaret

I'm not exactly sure what you mean by "mark a sudoku already solved by a play" but you can solve sudoku puzzles fairly easily with a program, just teach the program the rules of sudoku, then have it put the first number that doesn't break a rule into the first open spot, then put the next number that doesn't break a rule into the next open spot and so on, if you ever can't place a number, you have to go back and change the last number you placed (and you may have to do this multiple times). Hope this general algorithm is understandable.

It sounds like the questioner wants a python program that tells you if a puzzle is correctly solved or not. It isn't difficult in any way. First, make sure there are no blanks - quick check. Then, check every row to make sure it contains 1-9, check every column to make sure it contains 1-9. Finally, check each 3x3 box. You may want to hard-code the indexes for those as it will only be 9 3x3 box checks. I would use a shortcut solution. If I find a blank, return false. If any row/col/box doesn't have 1-9, return a false. If I get through it all without returning a false, return a true. --Kainaw ^(talk) 14:57, 25 September 2006 (UTC)

Mediawiki + NTLM

I have a problem on implementing NTLM on Mediawiki 1.7.1 on Ubuntu 6.06. i cannot get mod_ntlm to work on Apache2. it just don't compile. What i really need is a automatic login on windows infested intranet. Nothing fancy, i just want mediawiki to fetch username and password from Active Directory. I'm not too good with php. Any suggestions how to proceed to overcome this obstacle?

http://modntlm.sourceforge.net/

http://www.thebluesmokeband.com/mod_ntlm.php

--Ilmawi 12:50, 24 September 2006 (UTC)

could this work? does it work as a module? http://search.cpan.org/~speeves/Apache2-AuthenNTLM-0.02/

--Ilmawi 13:30, 24 September 2006 (UTC)

Access hidden options in BIOS and Memory Timing Settings

How can I access the options hidden by the manufacturer in the BIOS? I googled around and I tried the Ctrl+F1 and SHIFT+F2+ALT+F3 combinations but they didn't work. I use an Award bios with MS-6719 motherboard from MSI (which is an oem-only board). I am trying to avoid flashing my BIOS. The reason is that I wish to upgrade my RAM but unfortunately the Memory timing settings (CAS Latency and such) is hidden. I'm not sure if I need to modify them but I thought I would just make them available just to make sure.

Also is there a program that allows me to modify bios settings from Windows? --龙★Ukdragon37★翔^talk 14:33, 24 September 2006 (UTC)

I've never seen a windows program that can modify BIOS settings... In fact I think the only way to modify these settings is to use the BIOS configuration utility or to flash the BIOS with a BIOS that already has the settings you want --froth^{T C} 17:12, 24 September 2006 (UTC)

Actually, AOpen's Winbios[2] lets you acess the bios setup screen but it only works for AOpen motherboards. Also a program called AMISetup seems to do what I want but it only supports AMI bioses. The program CtCHIPZ supports other bioses but I do not have the chipsets required. I know how to modify a bios image file to unhide the settings but that involves flashing. Unfortunately my computer is shared and I am very much afraid of other users' wrath if I mess it up. I am planning to upgrade to PC3200 DDR memory modules even though my motherboard only supports up to PC2700. The PC2700 version of the same modules were selling at the same price so I thought I would get the faster ones. Is it really that necessary to access the RAM Timing settings in the BIOS or should just install and hope for the best? ----龙★Ukdragon37★翔^talk 17:27, 24 September 2006 (UTC)

Disconnecting without turning off modem

Since I use a always on DSL connection, and use it through an Ethernet port, I must turn off modem everytime I want to disconnect. Can I disable LAN by right clicking on it everytime I want to disconnect? If I disable and enable LAN, will it cause any trouble for LAN card or modem? Is there no problem if I do it and do it as many times I want? Is there any better way to disconnect than disabling LAN?

As far as I'm aware, disabling LAN is the only simple way to disconnect from the network without doing it to the hardware physically (unplugging the network cable etc.). There are other software methods (firewalls usually provide a "stop all network traffic" function for example) but obviously they are not bundled with Windows. Disable LAN in windows just makes the operating system disacknowledge the NIC so therefore it won't do damage to the hardware. Although this method is effective, every time the connection is enabled again it will do a connecting sequence, e.g. configuring from a DHCP server among other things, which will usually only take a few seconds but it may get on your nerves. The only alternative I think will be using a software firewall that has a one-click traffic-pinching feature wich jsut blocks all traffic in or out of your computer. --龙★Ukdragon37★翔^talk 16:13, 24 September 2006 (UTC)

Here's just two examples of firewalls that "pinches" network traffic: both ZoneAlarm and Norton Internet Security have the block traffic button on the top left corner, as you can see from the picture in their articles. --龙★Ukdragon37★翔^talk 16:19, 24 September 2006 (UTC)

files management

I always create file in one location.But the file is related to various folders.So i create shortcuts in other folders so that all shortcuts have the same target. The problem is when i make a back up copy in a CD or Flash drive the shortcuts are also copied with the same target.When i open that CD or flash drive in another computer the target file is not found in that computer.Is there any way to avoid this problem?

Try changing the shortcuts so that they use relative paths instead of absolute paths. See Path (computing). For example, suppose we have a directory "foo" in the root C: drive. Its path will be "C:\foo". Inside that directory we have a file called "file.txt" and another directory called "bar". If we create a shortcut linking to "file.txt" inside the directory "bar" we can either use an absolute path or a relative path. With an absolute path the shortcut will point to "C:\foo\file.txt" but with a relative path the shortcut will point to "..\file.txt" (literally meaning pointing to file.txt in the parent folder). They both serve the same functions and will yield the same result. However, if we move the folder "foo" onto a CD and load that into another computer, the shortcuts will stay the same. Therefore, the absolute path will still point to "C:\foo\file.txt" which probably does not exist on the hard drive of the second computer and a not found error is displayed. The relative path will still point to "..\file.txt" but because it says "go to file.txt in the parent folder" which actually means the file copied in the CD. Absolute path is a specific location which can be located from any directory but it may break if moved to a different computer. Relative path is an instruction telling where to go from the current directory therefore it will not break if moved into another medium as long as each location where it points to is also copied along with it. Hope you can decipher my seemingly meaningful drabble! :) ----龙★Ukdragon37★翔^talk 18:47, 24 September 2006 (UTC)

Thanks Ukdragon for very very valuable answer.That was what i exactly wanted.I tried it in my PC.But it did not work.I typed the relative path name on 'Target' box of the properties window of the shortcut.The system did not accept it saying 'invalid path name' or 'path name does not exist' [user:amrahs]

I just did more research and found that the inability to use relative paths is an inherent weakness in the Windows shortcuts file format. However, I have found a workaround. In the target field of the shortcut, put in "%windir%\system32\start.exe " (without quotation marks, and with the space after start.exe) and straight after it put in your relative path but surround the path with quotation marks. Then in the start in field put in "%cd%". Start.exe has the same effect as double clicking a file. What this does is it passes the relative path to start.exe which starts the file. The start in field is also passed to start.exe so it knows where to go from. The variable "%cd%" simply translates automatically into the current folder path. Therefore, using my example above, a shortcut in the folder c:\foo\bar linking to the file c:\foo\file1.txt will have [%windir%\system32\start.exe "..\file1.txt"] (without square brackets) in the target box and [%cd%] in the start in box. Then you can change the shorcut icon to match target file instead of using start.exe's plain program box icon. Hope this helps! ----龙★Ukdragon37★翔^talk 17:20, 26 September 2006 (UTC)

NVidia VGAs

I have a question. Which one of these two NVidia VGAs are more "powerful"? The GeForce FX 5200 (64 ou 128 Mb) or the GeForce4 MX 4000 (128 Mb)? Thank you. Answer urgent!! CG 19:13, 24 September 2006 (UTC)

If you read the table of GeForce FX models in its article you will see it being described as "Replacement for GeForce4 MX family." The answer is therefore obvious. By the way, the FX series is the 5th generation of the GeForce series despite it having an odd-one-out name. --龙★Ukdragon37★翔^talk 22:23, 24 September 2006 (UTC)

Also if you read the GeForce 4 article it describes the GeForce 4 MX as:"it is a GeForce4 in name only. Many criticized the GeForce MX name as a misleading marketing ploy since it was less advanced than the preceding GeForce 3. On its release, disappointed enthusiasts described the GeForce4 MX as a GeForce 2 MX with a better (128-bit DDR) memory controller." ----龙★Ukdragon37★翔^talk 22:26, 24 September 2006 (UTC)

Thank you a lot!!! CG 14:15, 26 September 2006 (UTC)

File Loss in Torrents

I've been downloading several 3+gb torrents using Azureus for the past couple of weeks. Recently Azureus has been crashing for an unknown reason. When I restart it everything is fine with my downloads. Last night Azureus crashed again and when I restarted 4 of the 5 torrents which were downloading which were at around 50-60% were all suddenly reporting that only 4% of each torrent was complete. On checking further I noticed that the pieces which remained were mostly clustered around the first files worth of pieces. Can anybody explain what's happened? I can see small amounts being deleted if it was corrupt but why would ~50% suddenly become corrupted when it's survived crashing in the past. --Kiltman67 20:49, 24 September 2006 (UTC)

Is your hard drive dieing? Run chdisk if you're on Windows. If not, use the corresponding disk scanner.--Frenchman113 on wheels! 21:11, 24 September 2006 (UTC)

I'll give it a try when I get the chance but it's doubtful as I only bought the hard drive about a month ago. --Kiltman67 21:37, 24 September 2006 (UTC)

Managed to solve the problem by forcing Azureus to re-check the torrents. --Kiltman67 03:29, 25 September 2006 (UTC)

Volume Loss (Computer)

I'm not a computer professional who knows all about computers so I need help! My computer's volume is gone and it's not coming back! I checked the troubleshooting part of my computer and completed all the instructions to get the volume back, but it still doesn't work. This happened before but one my cousins fixed the problem, but I don't know how he did it! So if anyone could help it would be much appreciated. Himanyo 21:19, 24 September 2006 (UTC)

There should be a loudspeaker icon in your tasktray on the bottom right corner. Double click it and uncheck any "mute" checkboxes. There might be other causes but try this first. Remeber if you use Windows XP you may need to use the arrow button on the tasktray to show all the hidden icons. ----龙★Ukdragon37★翔^talk 22:19, 24 September 2006 (UTC)

Nothing. Himanyo 00:53, 25 September 2006 (UTC)

One way that could happen is if you don't have a soundcard installed. If your computer is old, maybe you're having hardware problems with your soundcard? --Kjoonlee 03:19, 25 September 2006 (UTC)

• You can lose sounds if the computer is out of memory. If so, a reboot will fix the problem. StuRat 08:53, 25 September 2006 (UTC)

• Some applications "take control" of the sound, and may not return control once shut down. Again, a reboot will usually cure this. StuRat 08:53, 25 September 2006 (UTC)

• And, of course, the speakers themselves may have been turned off, unplugged from the electrical outlet, or unplugged from the computer. Check all of those. At work I used to have trouble with the cleaning lady disconnecting things to plug in the vacuum cleaner. StuRat 08:56, 25 September 2006 (UTC)

Been there. Done that! I appreciate your help, but it didn't work. Thanks anyways! Himanyo 23:56, 25 September 2006 (UTC)

If you're using Windows XP, did you try clicking Control Panel in the Start menu?—EdGl 03:05, 26 September 2006 (UTC)

If you're talking about having lost the volume control thing in the taskbar, what you need to do is go into your control panel (through your start menu), get to the sound control, and find the checkbox that says something like "show volume control on the taskbar". - Rainwarrior 20:35, 26 September 2006 (UTC)

Bmp in Java

How do I read a bitmap file (like from Microsoft Paint, or possibly PaintShop Pro) into and out of an array in Java? Black Carrot 21:52, 24 September 2006 (UTC)

I'm not a Java programmer (I deal in the much more mundane Visual Basic) but I did some googling and point you to this page:[3] which seems to have some links on reading image files of a variety of formats including BMP. ----龙★Ukdragon37★翔^talk 22:33, 24 September 2006 (UTC)

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.*;

public class Bmp
{
    public static void main(String args[])
        throws IOException
    {
        File file = new File("image.bmp");
        BufferedImage image = ImageIO.read(file);
        System.out.println("size: " + image.getWidth() +
                           " x " + image.getHeight());
    }
}

See also: google java read image file, http://javaalmanac.com/ (examples of often-used stuff) and http://forum.java.sun.com/ (helpful folks knowledgeable in Java). Weregerbil 11:21, 25 September 2006 (UTC)

It's not working. I looked those terms up in the help system and they sound like they're right, but as it's written (with "image.bmp" replaced with an actual file, of course) it outputs a null pointer exception. I changed it to System.out.println(image), and it outputs null, which the ImageIO help file says means it doesn't recognize the file type. Any ideas? Also, once I've edited it with the BufferedImage system, how do I write it back into the file? Black Carrot 17:01, 25 September 2006 (UTC)