Jump to content

Wikipedia:Reference desk/Archives/Computing/2007 August 6

From Wikipedia, the free encyclopedia
Computing desk
< August 5 << Jul | August | Sep >> August 7 >
Welcome to the Wikipedia Computing Reference Desk Archives
The page you are currently viewing is an archive page. While you can leave answers for any questions shown below, please ask new questions on one of the current reference desk pages.


August 6

[edit]

File and Print Sharing

[edit]

I am working on my girlfriends computer, ME unfortunately, and I am trying to set up File and Print Sharing with her other computer, XP, running Norton 360. I have put the IP range into allow, and it still doesnt work. Any Ideas?

Omnipotence407 00:21, 6 August 2007 (UTC)[reply]

What exactly doesn't work? And don't run Norton :). Splintercellguy 01:15, 6 August 2007 (UTC)[reply]
Assuming both are Windows, do not worry about IP addresses. Turn off all firewalls/anti-virus/computer protection programs for the moment (feel free to disconnect the Internet while doing this part). Right-click on the My Computer icon on each computer and set them so they have the same workgroup name but different computer names. They will need to reboot. Now, right-click on a folder and select Sharing and share it. If sharing isn't available, you must enable it in your network settings. Once you share a folder (and/or a printer) on each computer, they should see each other. If they don't, you probably have a networking problem. If you can see each computer in Network Neighborhood, you got it working. Now, turn back on all the firewalls/anti-virus/computer protection programs one at a time. One or more of them will block this sharing. You'll have to figure out how to get the program to stop blocking it. -- Kainaw(what?) 01:45, 6 August 2007 (UTC)[reply]

Here's exactly what wont work, the ME cannot find the printer that I have set up for sharing on XP, and each computer wont find the file on the other computer that is shared. I cant stop Norton bc/ its on her parents computer and they are paranoid.

as for Kainaw, I've done everything up to the turning off of individual programs.

Thanks for the help, if anyone has anymore ideas, id love to hear them, i cant try them out for another couple of days, but id love to go in with multiple strategies. Omnipotence407 11:17, 6 August 2007 (UTC)[reply]

I Tried to turn off everything, and it didnt work. Any other suggestions? --Omnipotence407 02:16, 9 August 2007 (UTC)[reply]

Its not that you should not run Anti Virus programs, its just that Norton specifically is a bad choice. Get your parents to choose a better Anti Virus programs. Theres avast! (free for home use), Kaspersky (40$ a year) or NOD32 (40$ a year), just, please, do not use Norton. As for your net problem, did you turn off everything or everything except Norton, because Norton itself might be the problem. — Shinhan < talk > 13:48, 10 August 2007 (UTC)[reply]

what are those things called?

[edit]

- is there a name for those twisted letters and numbers that come up when you're registering for an online mailing list or whatever, and you have to read them and enter them into a field in order to prove you're not a bot?

Thanks in advance Adambrowne666 04:36, 6 August 2007 (UTC)[reply]

They're called CAPTCHAs --Oskar 05:01, 6 August 2007 (UTC)[reply]
The name of these always make me laugh. When they recognise a user as not being a human, do we call them GOPTCHAs? Capuchin 08:30, 6 August 2007 (UTC)[reply]

Thanks for that. If I can't read the letters, does that mean I'm an AI? ;) Adambrowne666 23:05, 6 August 2007 (UTC)[reply]

File search in explorer in XP

[edit]

When I do a file search in explorer in XP, it insists on looking inside zip files. Is there anyway to tell search not to do this? -- SGBailey 08:45, 6 August 2007 (UTC)[reply]

Unregister the zip file handlers: regsvr32 /u %windir%\system32\zipfldr.dll --soum talk 09:09, 6 August 2007 (UTC)[reply]
Thanks. Worked a treat. -- SGBailey 09:28, 6 August 2007 (UTC)[reply]

oo confusion

[edit]

Is an object orientated programming language in essence a procedural language with built in support for a non-uniform data structure?

Or have I totally misunderstood, or missed addition features?87.102.34.140 10:26, 6 August 2007 (UTC)[reply]

OO is more than that. It attempts to repackage functionality into logical components. A very simple example is that a car has a dashboard, an engine, and wheels. The dashboard controls the engine, and the engine controls the wheels. The driver doesn't have to think about manipulating the engine, or turning the wheels, the driver simply manipulates the dashboard. Each component does it's own job. There's more to it of course, RTFA for more.
(doesn't the engine analogy apply to a well set out pascal program for example?)
ok so 'message passing' between proceedures/sub programs is included/supported - that's a sensible way to program complex systems. But was my summary too simple or what?87.102.34.140 11:06, 6 August 2007 (UTC)[reply]
Have you read the article on OO? Give it a try. You can't model inheritance in Pascal; using the same analogy, you could specify common functionality across all Dashboards and make the Dashboard for a car more specific -- add a gearshift lever for a Car, but you might not need this for an Aircraft dashboard. It's not so easy to model private and public variables/fields in non-OO languages either, nor can you create well-defined interfaces that are attached to data types in non-OO languages.
ok that's more specific - obviously inheritances is modelable in pascal (or any other language) but tediously difficult to do. Having support for a tree like data structure (or other) helps reduce the brain-ache.
I far as I can think the "repackage functionality into logical components" is not far off using discrete proceedures with set input and output fields for any 'operation' or function. Clearly most simple non 'oo' languages don't have support for a non-uniform databases, and so definately won't have any functions ('methods' in oo parlance) for getting info from such a database..
I just wanted to know if my simple summary was right or not - a yes or a no.87.102.34.140 11:37, 6 August 2007 (UTC)[reply]
You can have make-believe inheritance in non-OO languages but you cannot simply state that your new object inherits everything from a superclass and then go away and work; I believe you would have to copy everything by hand yourself.
You can have functions that operate on structures, but they are in no way tightly associated to the structure like an actual method is. Say for example in C I have a Vehicle struct and some functions start(struct Vehicle), stop(struct Vehicle), and steer(struct Vehicle). But a struct Car is a kind of Vehicle, but you can't start a struct Car because you've only defined start for Vehicles. Inheritance takes care of this typing problem.
Clearly for 'oo' inheritance is a bog standard feature nowadays. But if a programming lacks this feature/function but has the others is it still 'oo'?87.102.34.140 12:37, 6 August 2007 (UTC)[reply]
I'm not 100% sure what you mean by nonuniform data structure, but I think your summary only vaguely describes what an OO language can do. It's like saying a computer is in essence can compute sums when in fact there is much more to what a computer can do.
I meant data structures other than simple arrays (eg 10x10 array of integers) - including trees (of varying length arms, containing any data type), and also nets (with if necessary pointers between nodes giving relationships between data (eg son/daughter,mother/father,brother/sister to give a simple example)
By the way, if you mean non-uniform database/data structure as a structure that contains objects of different types; then this is a matter of typing. It can be argued that statically typed OO programming languages have a much more cumbersome time dealing with classes of objects that have different types but are somehow related. Dynamically typed OO programming languages are much more flexible and can handle heterogeneity in data types much more flexibly.
I was thinking 'dynamically' eg like LISP. also see above - effectively extending to a random network of connected nodes were each node contains any sort of data. (thanks for your help by the way)87.102.34.140 12:38, 6 August 2007 (UTC)[reply]
You can do that with any programming language; it doesn't need to be an OO programming language. You can do this with C, for example. Anything which supports a "struct"-type or composite datatype can do this.

question 2 - slightly more focused

[edit]

What would be the absolute minimum for a language to be called 'object orientated' - I have suggested a "(proceedural?) language with built in support for a non-uniform data structure" ?

By non-uniform data structure I mean upto and including a random network of nodes, each node containing any type or number of data elements, as well as obviously simpler structures (tree, array etc).

Is there another name for such a language similar to the above that does not necessarily support concepts such as inheritance 'out of the box'

(Question not high priority - I think I've got the hang of this now) Still would appreciate any answers.87.102.34.140 12:47, 6 August 2007 (UTC)[reply]

First, it's "object oriented", not "orientated".
The absolute bare minimum, as the name suggests, is support for objects. An "object" in this context is a data structure that includes the functions or "methods" needed to manipulate it. In C++ parlance, the essential feature of a class is that you can declare functions inside it.
Running a close second in importance is inheritance.
Those two are the biggies. Everything else (overloading, polymorphism, etc.) is window dressing. :-)
Steve Summit (talk) 13:34, 6 August 2007 (UTC)[reply]

OK I've got enough now for my dictionary definition, thanks everyone.87.102.34.140 18:33, 6 August 2007 (UTC)[reply]

speed restrictions

[edit]

After doing a few speed tests at speedtest.net, I realized that my connection speed had dropped considerably, from about 11 mbps to only 1 mbps or so. I repeated my test 10 or so times, waiting for the latency each time. Of course, my download speeds are much slower than usual from around 500 KB/s down to around 90 KB/s. Last month I downloaded a record amount (I can't always be sure, though). Is it possible that my ISP (Cox) may be restricting my speed because of the high bandwidth volume? If so, when should the speed be back up? Should I be concerned that they are spying on me? --hello, i'm a member | talk to me! 11:34, 6 August 2007 (UTC)[reply]

To my knowledge the term for such a thing is called "shaping" and this depends on the type of account you have - I believe the best advice is to phone your technical support and ask them a) if you've been shaped b) if they're aware of any service disruptions that could affect your download speed, c) why is your download speed so low? Rfwoolf 14:47, 6 August 2007 (UTC)[reply]
This may be the case. My upload speed is still largely unchanged and streaming seems to unaffected. When will my speed be restored? I've heard that some 'shaped' customers have their speed (or more correctly, bandwidth) restricted for less than a day, while others more than a year. --hello, i'm a member | talk to me! 17:51, 6 August 2007 (UTC)[reply]

bees in my head

[edit]

Sitting here with the headphones on and plugged into the jack on the PC; if there's nothing playing to mask it, every now and then there's an angry buzzing flying around in the headphone space for a fraction of a second. It's not 60 hz noise or anything like that, it's some kind of digital crap that for some reason is leaking into the audio. From reading here and there I know that it's a pretty common complaint by people who listen in similar circumstances, so it's not just my PC. Anybody have any reliable ideas re what it is and what can be done about it if one wishes to actually make the PC the hub of an audio system? Gzuckier 14:51, 6 August 2007 (UTC)[reply]

I got a milder version of this when my headphone volume was at 100%, even dialing it down fractionally caused this to disappear. I also got huge feedback when I boosted my microphone volume when using TS or Ventrilo and you might want to knock any boosting effects your soundcard might have enabled off. (How did I solve my problems? My Jack Russell was a pup at the time and handily bit through leads for me. My new headphones are fine except for a light fuzz at top volume). Lanfear's Bane
You can shield and isolate all you like and you still may not nail it, trust me. Save youself a lot of trouble and go external, the only reliable way to get computer noise out of your audio is to take the audio out of your computer, i.e. get an external soundcard, or at least a half decent PCI one, you can get them cheap these days. Vespine 01:34, 7 August 2007 (UTC)[reply]
I bet you have a GSM cell phone. They turn on and off their transmitter fifty times a second. Although the frequency is far too high, the 50hz on/off cycle generates a 50hz buzz in unshielded amplifiers. --Mdwyer 05:39, 8 August 2007 (UTC)[reply]
This happends to me when I've got a lot of read / writes on the hard disk; like when you can hear the disk being accessed and that somehow gets into the audio feed. Think outside the box 13:38, 10 August 2007 (UTC)[reply]

website design

[edit]

2 questions here really,

first, i've made a webpage and its currently sitting on my pc but when i view it its stuck on the left hand side of the screen. i've realised this is something to do with the screen resolution that i view it at. as when i view it at 800*600 res its fine everything is centered and its spans the whole of the screen but when i go to higher resolutions it doesnt span the right side of my screen, is there a piece of code i could put in to get it to span the whole of the screen regardless of the screen resolution? i've tried using the center command but that doesnt make it span the whole page.

second question, what tips could you people give me to help my page look professional? i know its subjective but any ideas or things to avoid would be helpful, thank you very much--Colsmeghead 15:11, 6 August 2007 (UTC)[reply]

Easiest solution for the first one is to put width="100%" wherever you set the width.
And for the second question, nothing to me sticks out as more unprofessional than color scheme. Blue #0000FF background and yellow text? Red background with green text? Stuff like that makes me want to close that page as soon as humanly possible. In general, stick with color schemes that have a light background (very light blue is a-ok) and use black text (unless you have a specific artistic reason, like black background with light grey text), but do those sparingly. And don't use too much javascript mouseover stuff. I personally prefer CSS style text-based mouseovers, because they are fast and don't require images to be loaded, nor javascript enabled. --Wirbelwindヴィルヴェルヴィント (talk) 16:01, 6 August 2007 (UTC)[reply]
The most important thing to do to make it look professional is to make the looks serve the purpose. If you make sure people will find whatever they want as quickly as possible then they will care little how it looks. But of course some make-up that doesn't get in the way of functionality (always make sure of that) won't hurt. But how much make up is needed depends entirely on the people you target. For example, look at the clean style of Wikipedia. It's totally info-oriented and therefore uses little colour. Computer geeks would probably even prefer plain text without any make-up at all. But for a site that deals with, say, children's computer games, lots of colours might be better. Maybe even animations. But a word of warning on that. The one single thing that I find most irritating on websites (and I'm certainly not the only one) is flash animations. It's horribly annoying to want to read something while something is flashing right next to it. Animations unavoidably draw the attention, that's how the human mind works. Advertisers know that and therefore use them a lot. Another irritation is PDFs, but animations are way at the top of the list of irritations.
Also resist the temptation to use various tricks just because you know them, another common mistake. Even professional designers do that to impress their employers, alas often successfully. DirkvdM 18:10, 6 August 2007 (UTC)[reply]

computing

[edit]

just bought a comp.am trying to pimp it.anyone knows a nice software they can recommend i want to change my boot screen when my comp reboots and also i want to change the sound scheme when i do functions like minmize the window.maximize blah blah.i have tried a few but none is so impressive.advise am on xp recently i was extracting a file.it was a large file anyways halfway the extraction when i placed my hand near the power supply unit it was as hot as an iron.then midway the extraction my comp shut itself down.the cpu was still running but the screen went blank for like 3 minutes then it turned itself back on.is my processer weak or something.it does that anytime it does a large function

1- Read KDE, and go from there. 2- It's an overheating problem. Make sure your fans are on and working, you might also have to put more fans in to cool it --L-- 17:13, 6 August 2007 (UTC)[reply]

How can we use data management and storage to get timely information ( Darkuah 17:49, 6 August 2007 (UTC))[reply]

Can you figure out what book this came from?

[edit]

I found a pdf of a book chapter posted on the website of an Indian university. I'd really like to find out what book this chapter is from. I tried my best searching for it, but I'm sure I don't know all the tricks. I wasn't able to find any good clues from pdf file or the website that links to it. My gratitude if you can figure this out! ike9898 17:58, 6 August 2007 (UTC)[reply]

here's the pdf file -- slow server, it takes a minute to load
The root directory has more chapters from the book in it (Ch. 7 is LightScat.pdf, Ch. 6 is Viscosity.pdf). My bet is that it is not a published book, but something made in-house by one of the professors at the university. My reasoning on this is that the entire thing was typeset in LaTeX, the images look home-made (esp. in the Viscosity chapter), and because, as you noted, they are devoid of any bibliographic information typically found in published books. That's just a guess, though, but they look like the kinds of mini-textbooks that science professors often develop for their courses. --24.147.86.187 20:48, 6 August 2007 (UTC)[reply]
Note that after writing that, I found this notation the page linking to that file: "document obtained from MSE 5473 course of University of Utah)". So it is indeed a professor's in-house textbook, but not from that university. (How'd I find that, you ask? I went to the root directory and from there found a few HTML pages which linked to the files in said directory.) --24.147.86.187 20:48, 6 August 2007 (UTC)[reply]

page disappeared

[edit]

Hi,

Last couple of days I found an interesting page at the address http://en.wikipedia.org/wiki/Computer_cooling. However, if I search again on Wikipedia for this page (I enter in the search field words such as "computer" or "cooling"), I got the answer as if this page is still online. If I click on the link to enter the page, I get in Mozilla the following message:

"File not found

Firefox can't find the file at /wiki/Computer_cooling.

  • Check the file name for capitalization or other typing errors.
  • Check to see if the file was moved, renamed or deleted."


I wonder if this page is still available and how can I reach it. Any info is apreciated.

Thanks,

Iulian

The links works for me. Looks to me like you're telling Mozilla to look for a file on your computer at /wiki/Computer cooling. Is that perchance what it says in the address bar, in stead of the full internet address? What happens if you click the link you yourself provided? DirkvdM 18:22, 6 August 2007 (UTC)[reply]
Thanks for your answer DirkvdM. Sorry for late, I haven't checked that page for a while, nor get back here to provide details. Here I am now :) . To answer your question (thou' I have no clue what 'perchance' word means) - this is what I type in the address bar: http://en.wikipedia.org/wiki/Computer_cooling. I presume that Firefox check the link first, and if it can't find it, then it checks the domain under which the page is located. If the domain exists, then the message is very clear: because Firefox can't find the page "Computer_cooling", located in the path "/wiki/Computer_cooling" (which does not exists, at the moment of check) on the domain "http://en.wikipedia.org" (which exists), check the file for capitalization or check if the file was removed.
Since this page worked for you when you checked (I checked now, at the moment of typing, and it also worked), then I presume that for some reason, when I asked for help the page wasn't available.
I can say the issue is fixed now, and if it happen again, I'll ask again for help. Thanks once again. Cheers!
Iulian

Geforce 8800 and Core 2 Quad

[edit]

How powerful of a power supply would i need for this combination?

600W is cutting it. I'd go for 650 if you were on a budget (lol) and 700W normally. -Wooty [Woot?] [Spam! Spam! Wonderful spam!] 20:04, 6 August 2007 (UTC)[reply]

Does this include fans and all? Thank you.

Yes. Vespine 00:53, 7 August 2007 (UTC)[reply]

Awesome. It's within my budget then. Blender, here I come ;)

I was in a similar quandry. I wanted enought for a High end graphics card, and a lot of hard disk drives. My friend recommended I get one with at least 40 Amps on the 12v rails.
This is the one I bought:
http://www.newegg.com/Product/Product.aspx?Item=N82E16817341010
OCZ StealthXStream OCZ600SXS ATX12V / EPS12V 600W Power Supply
and this was in the reviews:
"Pros: It handles fine a single, overclocked 8800GTX with a C2D processor. It has 600w for a lot of power to handle.
"Cons: Doesn't have modular cabling, but hey, it's good enough for the price.
"Other Thoughts: I've read and heard that this can handle dual 8800GTX cards without any problem, so it would be a waste to buy a higher wattage PSU than this one.
Artoftransformation 18
54, 7 August 2007 (UTC)
OCZ has terrible customer service and rebate turn-around time, and the 700W PSU I got from them had a capacitor explode the first time I turned it on. -Wooty [Woot?] [Spam! Spam! Wonderful spam!] 21:05, 7 August 2007 (UTC)[reply]
I have not heard of OCZs customer serivce problems, and several discussion forums give favorable reviews. Capacitor failure is the most common of early device failures, and can happen to any manafacture. From what I know of the computer industry, NO company has EVER had good rebate turn-around time. NONE. We'll see how fast they turn this one around Artoftransformation 09:25, 11 August 2007 (UTC)[reply]

traffic shaping

[edit]

I'm afraid that my traffic is being shaped. My download speeds have been slow every since I dl'd 40 GB or so last month. When does Cox (My ISP) usually restore a customer's 'speed' after shaping? --hello, i'm a member | talk to me! 19:41, 6 August 2007 (UTC)[reply]

Most likely it is at the start of your next billing cycle. Your ISP's home page should have a facility to log in and check your account and when your billing cycle starts, it's either based on the 1st of the month or the date you signed up, so you won't be able to work it out without checking it with your ISP. Vespine 00:50, 7 August 2007 (UTC)[reply]

Can i save my computer?

[edit]

The power plug going to one of my hard drives came out while i was using the computer. that instantly turned off the computer. i unplugged the computer from the wall then plugged it back in, reattached the power cable to the HDD. and turned the computer back on. an error appeared during the BIOS saying "Disk boot failure, insert system disk and press enter" I checked the bios and everything was configured correctly, and it was. After that i switched out the ide cable and used another free power cord to attach the HDD. Then i tried booting from a CD and then another HDD, but none worked. is there any way that i can fix this. i think it might be that i ruined the motherboard, if so will i have to replace it.

Yeah, you're hopeless. Most everything should be fine, so get a new motherboard and CPU. --hello, i'm a member | talk to me! 21:06, 6 August 2007 (UTC)[reply]
It's possible that you fried your IDE port. You could try using another, if your motherboard has more than one IDE port. --cesarb 23:39, 6 August 2007 (UTC)[reply]
No no no. There's no guarantee that it's your motherboard. In your BIOS you tell your PC the order of devices it must try boot from, e.g. first from floppy (A:), then from CD (D:), then finally from hard drive (C:). The "disk boot failure" comes when it found no device to boot from. So one possibility is that your BIOS is set to only boot from your hard drive (C:), and it tries to, but the hard drive's not working, it has no alternatives, so it tells you it can't boot from the disc. This means that your hard drive might be broken but not your motherboard. One common possibility is that your hard drive was writing to the file table when its power was unplugged, thereby the file table was corrupted - and when you plug in your hard drive and it tries to make sense of the file table it finds its corrupt, and therefore can't access any of your files. This is a common problem with certain external harddrives. You need to then consider your options: The easest thing to do is just format your hard drive - this clears the drive and resets your file table which would solve the problem (but whipe your data). If losing your data is a major problem, then you'll need to hook up your hard drive to a working computer as a secondary or slave drive (i.e. not the main drive or the drive that the computer will boot from). Get into an operating system (e.g. Windows XP) and try to access the drive in question. You might be delighted to find that the drive is accessible and you can take some data off. Alternatively you might be shocked to see that you can't access the drive at all, or it is completely empty (Note: It is not completely empty, just your file table is corrupt - so the drive's index doesn't know what's on it). If that's the case you'll need to look at data recovery software (or a data recovery company in a worst-case scenario) which can do quite a few things 1) It can possibly repair the file table, 2) Even if the file table is completely obliterated, it can scan the entire drive from beginning to end looking for files, making a list of them, and then either transfer the files off, or ask it to rewrite the file table.
One thing I haven't mentioned is how you determine that it isn't your motherboard. Well if your computer boots up enough to tell you that it has a disc boot error, I'm almost positive it isn't your motherboard - because if it was your PC probably wouldn't even boot up the BIOS.
The other thing is the IDE port/cable. You can test if this is working by connecting another drive to it, even a CD rom drive. (For example set your BIOS to boot from CD, put in a Windows XP install disc -- or any operating installation disc that can boot -- connect your CD ROM, and try boot -- if it can read the CD, then the IDE port or cable is fine.)
One finaly thing: It is of concern that your PC died when you pulled the power out of the Hard drive - I'm not sure why that happened or what must have tripped when it happened. But by your story your computer is willing to load the BIOS, so that's all good, now its just a matter of the IDE port (unlikely), the IDE cable (possible and likely because both your CDrom and HDD don't work when attached to it), or its the hard drive.
Good luck Rfwoolf 14:18, 8 August 2007 (UTC)[reply]

PHP user management

[edit]

Can anyone recommend a good, easy, and customizable library for user management on a website? Simple stuff like registration, sending a verification email, and editing a profile? I can find lots of examples of these sorts of things, but is there one that stands out? --70.161.254.52 20:50, 6 August 2007 (UTC)[reply]