Wikipedia:Reference desk/Archives/Computing/2009 November 1

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November 1[edit]

bad impacts of information system to an organisation[edit]

can anyone tell me what is the bad impacts of information system to an organisation?? i need more information about this.. waiting for your reply soon —Preceding unsigned comment added by 60.48.253.97 (talk) 05:24, 1 November 2009 (UTC)[reply]

Please do your own homework.
Welcome to Wikipedia. Your question appears to be a homework question. I apologize if this is a misinterpretation, but it is our aim here not to do people's homework for them, but to merely aid them in doing it themselves. Letting someone else do your homework does not help you learn nearly as much as doing it yourself. Please attempt to solve the problem or answer the question yourself first. If you need help with a specific part of your homework, feel free to tell us where you are stuck and ask for help. If you need help grasping the concept of a problem, by all means let us know. Tempshill (talk) 05:46, 1 November 2009 (UTC)[reply]
... meanwhile, have you read our articles on Information system and Information systems discipline? An appropriate and well-designed information system can be an enormous benefit to an organisation. The opposite can be a disaster! Dbfirs 08:04, 1 November 2009 (UTC)[reply]
I have to add my two bits - an appropriate and well-designed information system will bring zilch benefits if the people don't use it or don't use it properly. I experienced this myself - installing something isn't enough, it should be run often and be used, too. --Ouro (blah blah) 11:57, 1 November 2009 (UTC)[reply]

to Tempshill: i not just want the answer... i just dunno what is the bad or disadvantages of information system to an organisation... so i post here to get some information... so that i can concentrate on the information i get here and try to understand it.. and this is not my homework... just for my self study... if u can please give me some information about it.. or you can tell me about your experience or any cases about this happened to you... i will very appreciate for your information... —Preceding unsigned comment added by 60.50.111.87 (talk) 14:12, 1 November 2009 (UTC)[reply]


i found that one of the disadvantages of IS is>> Everything has to be kept private at all times. This could be hard to do. anyone can tell me why it is hard? —Preceding unsigned comment added by 60.50.111.87 (talk) 16:27, 1 November 2009 (UTC)[reply]

Yes, computer privacy and security are big issues here if the information is at all sensitive. The organisation needs to employ technicians who are totally trustworthy, and to use a database system that prevents unauthorised users copying the data. And Ouro makes a good point: the system will be a disaster if the users are not willing and well-trained. Dbfirs 09:32, 2 November 2009 (UTC)[reply]

Unknown website[edit]

Hello there, I am having trouble with an unknown website. Whenever I tried to connect to internet this webpage automatically opened up. I cleaned browser and ran spyware search and destroy software but nothing happened. How can I get rid of this nasty webpage? Thanks--119.30.36.35 (talk) 11:25, 1 November 2009 (UTC)[reply]

Autostart? Home page settings of browser? Settings of dial-up application (or whatever you use to connect) to automatically open a specific page was effected? What was the usual case before this site started harassing you?
Try installing a different browser (i. e. Opera if you are normally a Firefoxer) and see what happens. Come back then and tell us what happened. --Ouro (blah blah) 11:54, 1 November 2009 (UTC)[reply]
If you use Internet Explorer then run HijackThis to see if it picks anything up. Rjwilmsi 13:58, 1 November 2009 (UTC)[reply]
Check your hosts file.–RHolton– 23:48, 1 November 2009 (UTC)[reply]

Vista Sidebar RSS Gadet Text-Rendering Anomaly[edit]

Since the day I upgraded to Windows Vista (= the day it was made available in Sweden), I have wondered why the exactly (seemingly, at least) same string is rendered in different ways sometimes in the RSS sidebar gadget. See this image for an example. Normally, computers are highly predictable and deterministic, so it is rather surprising that the same string is rendered differently on different occasions. Exactly when does this happen? Why? Can you give me an example from Win32 API when this happens? --Andreas Rejbrand (talk) 13:15, 1 November 2009 (UTC)[reply]

Could it be there is some HTML code in the original source feed that is causing one entry to display in a Narrow font? Sussexonian (talk) 22:15, 2 November 2009 (UTC)[reply]
I did not believe that this simple gadget respected HTML tags. But you might be right - it sounds fairly reasonable. Unfortunately, however, I do not have access to the code that generated the image any more. But there might be more examples in the future. --Andreas Rejbrand (talk) 08:45, 3 November 2009 (UTC)[reply]

pixel intensity??[edit]

every image is saved by a computer in form of a intensity matrix,defining a value for each pixel.can any one tell me in which units the values are so that i can apply some radiation formulae like weins law,stfans law on it. yours sci-hunter SCI-hunter (talk) —Preceding undated comment added 14:37, 1 November 2009 (UTC).[reply]

There are many ways to store images. See image file. The Graphics Interchange Format article has some good technical details. --Sean 16:05, 1 November 2009 (UTC)[reply]
Image file formats store intensity data in an abstract, dimensionless quantity. Computer display technologies take this information and use it to emit light of the appropriate intensity; often there is a bounded linear relationship between the value in the image file and the intensity, in other cases a gamma nonlinearity is applied. This gamma is partially a function of the characteristics of the display device (and it settings), of the graphics hardware and it settings, and sometimes (as is the case with formats like PNG) gamma information is encoded in the original image. So if you're looking for a concrete physical value, you need to know a lot about the capabilities and calibrations of the particular display devices involved - in practice they vary quite a lot in terms of their intensity curve, frequency response, and colour gamut. -- Finlay McWalterTalk 16:20, 1 November 2009 (UTC)[reply]
(EC) This entirely depends on the image file format. It is possibly GIF, but it might also be PNG, BMP, JPG, TIFF, XPM, TGA, etc. See bitmap (BMP) for a far more simple image format than GIF. In a BMP file, after all headers and the optional palette, the image data might be RLE compressed. If it is not compressed, and if the bitmap is 24-bit (the simplest case), each pixel is represented by three bytes (i.e. 24 bits), each byte (a number between 0 and 255) being the B (blue), G (green), and R (red) RGB coordinate of the pixel. Normally (depends on the sign of the height value in the header, if I remember correctly) the scanlines (lines of pixels) are stored bottom-up (rather than the more intuitive top-down order). Also, one must take care of padding bytes in the end of each scanline... --Andreas Rejbrand (talk) 16:22, 1 November 2009 (UTC)[reply]
Also, some images embed a ICC profile which attempts to regularise the relationship between colour values in the image and actual colour values in the output; this still doesn't get you to absolute physical intensity levels, as there's still plenty of scope for variety of intensity between different physical display devices. -- Finlay McWalterTalk 16:30, 1 November 2009 (UTC)[reply]

explorer.exe[edit]

explorer.exe from windows 95 was able to run in Windows 95, 98 and ME. Why doesn't it work in XP or Vista, when even the much older progman.exe from Windows 3.1 still works? Also, why doesn't explorer.exe from XP work on Vista? —Preceding unsigned comment added by 82.43.88.201 (talk) 16:45, 1 November 2009 (UTC)[reply]

Why do you want to run a different browser on a different OS? The usual reason is checking out web development efforts with various browsers, but maybe that is not your reason. --DThomsen8 (talk) 18:21, 1 November 2009 (UTC)[reply]
The OP is asking about explorer.exe, which is the program for Windows Explorer the file browser, not Internet Explorer the web browser. --KageTora - SPQW - (影虎) (talk) 20:51, 1 November 2009 (UTC)[reply]
Yes. Internet Explorer is named iexplore.exe. --Andreas Rejbrand (talk) 08:59, 2 November 2009 (UTC)[reply]
The first answer does not address the question. The person asking didn't say they wanted to do this; they asked why it wouldn't work.
Computer programs are sets of instructions that run in a certain environment; by that, I mean that the instructions can call on their environment to do certain things for them. When a program wants to connect to the internet, or read a file, or get the current user's name, a program often has to do different things on different operating systems, and even on different versions of the same operating system.
Microsoft made some things compatible among different versions of Windows, and some things not. For some period of time (evidently), the instructions used on W95, 98, and ME were compatible with all three versions. So the version of the XP browser that runs in Vista must have to do some things that are not available in Windows 95. This is common; as an environment such as Windows ages, changes and additions are made, and it is difficult (and arguably unnecessary) to maintain compatibility for very long. Keep in mind that Microsoft makes its money selling software, not keeping things compatible for years and years. Besides that, often new features require instructions that were not thought of and therefore not available in the older system. ralphcook —Preceding undated comment added 18:55, 1 November 2009 (UTC).[reply]
Though, on the last point, it's worth noting that the #1 selling point that people use when discussing why they stay with Windows (despite its many flaws) is that it is compatible with the most number of people, and etc. So some compatibility is built into their business model—it's part of the reason people use their software in the first place. If they neglect that, it will definitely impact the business model. That being said, expecting a core system program from 14 years ago to still work on every operating system is a little bit extreme. Your time would be better spent figuring out what it was about that program that you liked and finding a modern equivalent (which probably exists). --Mr.98 (talk) 01:58, 2 November 2009 (UTC)[reply]

Thank you for the interesting answers. I am still confused though; why would explorer.exe be too old to work yet ever older programs from Windows 3.1 like File manager and Program Manager still work on XP and Vista? —Preceding unsigned comment added by 82.43.88.201 (talk) 09:22, 2 November 2009 (UTC)[reply]

The age of the program does not, by itself, make a difference. What matters is what instructions it has in it. Programs have instructions in them that ask the operating system to do things for them, and for it to work, the operating system must be able to satisfy those requests. As Windows has aged, clearly some requests have kept their same "format", i.e., the way a program makes its request in Win98 is the same way it makes that request in XP. But some requests have been removed, or their format has changed, so when a program makes that request the "old" way, the "newer" operating system does not understand what it is asking and the request does not work.
A program can be written to make requests either way, depending on the operating system on which it is running, but an older program cannot usually be programmed to run on an operating system that is not in existence when the program is written.
So I expect that programs that still do work only make requests that are still there and still in the same format, and programs that do not make requests that are not still there or now in a different format. —Preceding unsigned comment added by Ralphcook (talkcontribs) 16:51, 4 November 2009 (UTC)[reply]

Isn't the answer that Win95 Explorer used the Win95 style Registry, which is not the same as the XP registry, while File Manager doesn't use the registry at all (obviously) but only WIN.INI or something similar? The more intriguing question is why WinVista Explorer doesn't work in WinVista.Sussexonian (talk) 22:14, 6 November 2009 (UTC)[reply]

External hard drive blocked[edit]

I just moved all my files from my Noteship external hard drive to another which worked great but it's now not allowing me to put anything new on it anymore... Every time I try to add something to it it tells me I don't have permission and that it's "read only". It was never like this before and if anyone could shed some light on this issue that would be greatly appreciated. Pineapplegirls (talk) 18:18, 1 November 2009 (UTC)[reply]

What is the external drive formatted as (e.g., NTFS, FAT32?), and what is the OS you are using to access it with (XP, Vista, Windows 7, Mac OSX?)? --Mr.98 (talk) 20:43, 1 November 2009 (UTC)[reply]
Not sure what has caused the problem, but, I would suggest (if you are using Windows) right-clicking on the drive, selecting properties, then making sure that 'read only' is not checked - if it is, then uncheck it. --KageTora - SPQW - (影虎) (talk) 20:47, 1 November 2009 (UTC)[reply]

I'm using Mac OX and i'm not sure how it's formatted... How should I check that? thanks for your help

In Finder, click on the drive (should be on your desktop when connected), then go to File > Get Info (Apple+I). Look for the line that says "Format". My bet is that it is formatted for NTFS, which OS X can read, but cannot write.
If you are only going to use the drive with Macs, you should reformat the drive as "Mac OS Extended" format (using Disk Utility—but be aware it will clear the drive when you do this!). If you are going to use it on both PCs and Macs, you can format it as FAT32 (also with Disk Utility), though there are downsides to that format (it cannot handle files over 4GB in size, which depending on what you do, could be an issue). You can also, I believe, download software that lets OS X write to NTFS drives, though I've never used any myself (but if you Google it, it is out there). --Mr.98 (talk) 22:44, 1 November 2009 (UTC)[reply]

Ok, excellent. So if I format it to Mac and try to open or copy the files to a Windows drive will it work? Or will I just not be able to add anything to it from a windows OS?.. Thanks —Preceding unsigned comment added by 80.39.184.228 (talk) 12:44, 2 November 2009 (UTC)[reply]

I believe you'd have to install special drivers for a Windows (NTFS) drive to be able to read the Mac-formatted drive. I know, what a pain—Macs can't use Windows correctly, Windows can't use Macs correctly. It's like we're still in 1991 or something. FAT32 is the only format that can be read by both (and, as stated, it has issues, in particular with very large files), so if you need something that can work easily/instantly on both (not installing any special software), use FAT32 (which you can do in Disk Utility). (Remember, as I said, that reformatting in Disk Utility will necessarily wipe the drive clean the first time you do it...!) --Mr.98 (talk) 14:31, 2 November 2009 (UTC)[reply]
Actually Windows Vista and Windows 7 support writing and reading to UDF as does Mac OS X for a while (not sure but think 10.4.6 at least but I don't use Macs) and also of course most *nix variants (FreeBSD not sure, Linux since 2.6.2 possibly, Solaris not sure). However formatting drives as UDF is I believe often not that easy. (May be possible from the CLI, usually not from the GUI.) While UDF was originally invented for optical media, AFAIK there's no reason why it can't be used (or wouldn't work well) on different media. In fact because rewritable optical media suffers from the same limited write cycle as most flash memory but to a greater extent, UDF from 1.5 have added features to give something similar to wear levelling. While this isn't particularly relevant to extern al hard disks, it does have several advantages over FAT32 (notably including no 2GB file size limit). I've believed since perhaps 2004/5? that given the absence of a clear cut cross platform available by default option other then FAT* (excluding FATex64 or whatever it's called since that's problematic), moving to UDF would be a good idea but only a few people seem to have considered the same thing [1] [2] [3] [4] [5]. The difficulty formating drives as UDF, it's association with optical media and the slow demise of XP likely haven't helped. Nil Einne (talk) 16:46, 2 November 2009 (UTC)[reply]

How to protect a picture?[edit]

Is it possible to protect a picture that you uploaded in a a social networking site? Beyond water-marking it, is there something that can be done?--81.47.159.223 (talk) 18:26, 1 November 2009 (UTC)[reply]

No, it's really not. The very property that makes digital media so useful and flexible is how innately easy it is to copy, move, and change it. Whenever someone cooks up some half-brained digital rights management scheme to limit unauthorised copies of things, they make things much more difficult for people they still want to view the media, but not very much more difficult for anyone wanting to misappropriate it. -- Finlay McWalterTalk 18:29, 1 November 2009 (UTC)[reply]
(EC) Everything you can see on the screen, you can copy. In almost all cases, Print Screen is sufficient, and a 100 % identical copy is obtained on the clipboard. In some rare cases, e.g. in some games and other full-screen applications, this is not possible. But, of course, you can always replace the computer monitor with some recording device (connect the DVI/VGA cable, from the computer, to this device instead of a monitor). If not even this is possible, you can place a camera in front of the screen. --Andreas Rejbrand (talk) 18:35, 1 November 2009 (UTC)[reply]
(Also, you can usually just turn off hardware acceleration, and this usually makes it possible to take a screenshot.) --Mr.98 (talk) 20:52, 1 November 2009 (UTC)[reply]
I once ran in a race where organisers hired an events photography company to photograph each runner. They noted (whether by fancy image recognition or manual labour) everyone's bib number and you could go to their website, enter a bib number, and it showed you a photo of that person. But they made you install a special IE-only plugin to see the image, once that made a special directX surface on which to display the image (so to avoid the printscreen/screengrab), and that refused to work if you disabled directX. So they lost a huge number of people straight off, who wouldn't install the plugin, and more who couldn't, and more still who couldn't get it to work. Even if you did get it to work all you got was a small and heavily watermarked image. I later heard from a friend of mine who was involved with the race organisation that, out of about 25,000 runners, they'd sold about a dozen copies. Given that they had several (I think five) photographers on duty, they clearly didn't make money. I appreciate that it's difficult to make money when what you're selling is so easy to copy, but surely they'd have made some money had they just put the watermarked images on the web plain. -- Finlay McWalterTalk 21:11, 1 November 2009 (UTC)[reply]
They could have easily just uploaded a very low res version (looks okay at maybe 2x3 inches, but would look bad at a 4x6, then sold the full versions. I can't believe someone can be smart enough to set up a system with directx to do images but so dumb to realize it's unnecessary.
If you don't want something circulated at all, don't upload it anywhere. If you don't want people using it for high-resolution purposes (e.g. in a magazine, or whatever), don't upload a high-res version. If you don't want someone using something without your permission, your only real recourse is copyright law (threaten to sue), not a technical fix, and even that does not give you 100% control over the image (there are fair use exceptions). --Mr.98 (talk) 20:54, 1 November 2009 (UTC)[reply]

Google search[edit]

I know the answer to this and when someone tells me I will kick myself, but how do you search google if you want to exclude results from wikipedia. BigDunc 18:38, 1 November 2009 (UTC)[reply]

I don't know how to specifically exclude a site, but simply adding "-wikipedia" to the query has the same effect (rather more so, but if you're looking for sources in a universe uncontaminated by wikipedia, it's not a bad thing to also omit every page that even admits wikipedia exists from the search). -- Finlay McWalterTalk 18:41, 1 November 2009 (UTC)[reply]
Google: -site:wikipedia.org whatYouWantToLookFor. Be sure to include the hyphen before "site:" or you will only get results from Wikipedia.--el Aprel (facta-facienda) 20:35, 1 November 2009 (UTC)[reply]
Thanks for the help. BigDunc 19:37, 2 November 2009 (UTC)[reply]