Wikipedia:Reference desk/Archives/Computing/2011 September 13

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September 13[edit]

Buying a Kindle Wifi (NOT 3G)[edit]

I've decided to get myself a Kindle but there's something that's bothering me.

Where I live I cannot buy it from amazon.co.uk I have to buy it through amazon.com which ships to many international destinations. With the 3G version this would definitley be something to think about because of the different carriers (I think but it's not really important as I don't want the 3G version)

There does however appear to be different Kindle Stores which each have different content available based on region. So what I want to know is whether this is tied to the devices bought from each amazon website. From looking around on amazon it looks like it's something you can select and change. Is this so? Can I just change between Country/Store and download content from all of them (that doesn't really make sense to me as it sort of defeats the purpose of separate Stores).

The reason I want to know is because I don't live in the UK but I am studying there at the moment and spend most of the year there. So I want to know whether it matters which one I get and if it does which one I should get --178.208.218.41 (talk) 04:05, 13 September 2011 (UTC)[reply]

I think you meant to say you can't buy it from amazon.co.uk you have to buy it from amazon.com Nil Einne (talk) 04:24, 13 September 2011 (UTC)[reply]
I think you should try to buy the Kindle from wherever you expect to do most of your downloading. Copyright, and therefore availability of some books, is different in the UK. Dbfirs 07:08, 13 September 2011 (UTC)[reply]
I am ignorant about the Kindle, but would agree with Dbfirs as a general stance, because region locking is a fear. Comet Tuttle (talk) 17:55, 13 September 2011 (UTC)[reply]

ABOUT C,C++ IN ELECTRONICS AND COMMUNICATION ENGINEERING.[edit]

                 WHAT IS C  C++ IN ECE SYLLABUS?
                                   PLEASE TELL ME IN DETAILS.  — Preceding unsigned comment added by HIMEL DAS (talkcontribs) 04:23, 13 September 2011 (UTC)[reply] 
They are programming languages -- see C (programming language) and C++. (And please don't write in capital letters on Wikipedia.) Looie496 (talk) 06:05, 13 September 2011 (UTC)[reply]

computer hardware[edit]

QUESTION 1 : A user Rahim has a pc with windows XP Professional SP3 and 4GB of RAM but the system only detects 3GB and the 500GB harddisk only shows as 466GB.Please explain in details why this is happening to Rahim's pc.

QUESTION 2 : How much DDR2/DDR3 RAM does windows Vista and windows7 need to run optimally.Please explain in details.

QUESTION 3 : Ibrahim has a problem where the amount of DDR2 memory has halves instead of double after installed a 1GB module with two 512MB modules.Justify the situation that Ibrahim is facing with appropriate trouble shooting solutions. — Preceding unsigned comment added by Sunita93 (talkcontribs) 07:04, 13 September 2011 (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. AndrewWTaylor (talk) 07:58, 13 September 2011 (UTC)[reply]

QBasic[edit]

Is QBasic code the same as YAbasic? i.e

10 beep
20 wait 1
30 goto 10

And these:

if
endif
goto
gosub
for
loop
next
fi
wend
setrgb
etc.....

Could QBasic code be copied to Yabasic and vice versa? Please in Simple English, explain the coding differences. Thank you.--213.107.74.132 (talk) 08:53, 13 September 2011 (UTC)[reply]

The article for Yabasic says it has no line numbers, and goto and gosub are not supported, so most QBasic programs won't work in Yabasic. It seems Yabasic implements some unusual things such as user-defined data types, so most Yabasic programs won't work in QBasic. I expect some simple programs will work in both QBasic and Yabasic, but most programs would need altering. I don't have enough experience of either language to produce a comprehensive list of the differences, but the forum [1] should be a good place to find people who know. (Hmm, the top post is titled "Has Yabasic 3 died?". That's a bit ominous.)  Card Zero  (talk) 10:20, 13 September 2011 (UTC)[reply]
Be aware that the example above isn't a good example of what QBasic is capable of. QBasic supported line numbers for backwards compatibility with GWBASIC and BASICA programs, but was designed for using indented code blocks and subroutines. The code snippets in the built-in help system and the example programs provided with QBasic showcased these features and barely mention line numbers at all. --Bavi H (talk) 05:12, 14 September 2011 (UTC)[reply]
If you must use BASIC, and must reuse old QBASIC code, use something more modern that's designed specifically for QBASIC compatibility like QB64 or something with a few more features like FreeBASIC. Nevard (talk) 02:13, 14 September 2011 (UTC)[reply]

Windows 7[edit]

Can you install XP software and games on 7?--213.107.74.132 (talk) 09:02, 13 September 2011 (UTC)[reply]

Programs designed for Windows XP may run without problems on Windows 7. If there are problems, you may need to run in compatibility mode or install a shim (some instructions for compatibility mode here). If you are using Windows 7 Professional, Ultimate or Enterprise, you can also use Windows XP Mode, which is a separate download from here. It is a virtual machine integrated into Windows 7, onto which you can install Windows XP programs. -- Kateshortforbob talk 10:16, 13 September 2011 (UTC)[reply]

What about RCT3? Will that work? I've heard some people have problems with it on 7. Am I correct?--213.107.74.132 (talk) 15:24, 13 September 2011 (UTC)[reply]

You should probably ask the fan communities, such as http://rct.wikia.com/wiki/RollerCoaster_Tycoon_Wiki (which is not affiliated with Wikipedia). -- Luk talk 15:29, 13 September 2011 (UTC)[reply]

Yabasic[edit]

How can you make a game in yabasic? I know do your own homework, but just briefly explain the things I need to know to make a game.--213.107.74.132 (talk) 09:09, 13 September 2011 (UTC)[reply]

Here [2] is the Yabasic implementation of samegame. First it opens a window. Then it calls renew(), a subroutine which sets up a new game with everything cleared - for instance it sets the score to zero and empties the array which holds the blocks. This subroutine can be called again later when one game is over and it's time to start the next game. The next thing the program does is call main(), which is the subroutine with the main loop in it. That loop is the part of main() which is between the first "while (1)" and the last "wend". Inside this loop, it calls display(), which draws the current state of the array (the blocks) to the screen. Also inside the loop is another loop (again contained between "while (1)" and "wend"), the input loop: this checks for keyboard input with inkey$ and mouse input with mouseb(a$). The program will spend most of its time just going round and round this little loop, waiting for input. Besides all that, the program has some logic which creates the actual rules of the game and make it worth playing. If you can figure out which parts create that logic, strip them out, and put in your own logic instead, you'll have made a game - although at some point you might want to advance beyond games involving simple squares, but it's a start. I see yabasic 3 [3] will support SDL, Simple DirectMedia Layer, which should be handy for doing many things with sound and graphics, if they get it working.  Card Zero  (talk) 10:11, 13 September 2011 (UTC)[reply]

Thank's. How can you make a 3D Game in Yabasic. And how can you make a game in QBasic?--213.107.74.132 (talk) 11:35, 13 September 2011 (UTC)[reply]

I don't think you can access a graphics card from Yabasic at present - you might be interested in Basic4GL, which interfaces with OpenGL (OpenGL and Direct3D are the two main APIs, bits of software that fit between your program and the hardware, for sending commands to a graphics card). You can however still produce 3D graphics, if you don't mind them being slow: you'd need to make (excuse the lack of simple language) filled shapes which scale down the positions of their vertexes as those vertexes approach the vanishing point - this is a fun exercise, and I did it a bit in C using the ordinary Windows drawing commands (the GDI) before I discovered OpenGL. You'd also want to implement Z-buffering. Plenty of reading and messing about there, and it would all be fun, but would only be reproducing the most basic parts of the functionality which OpenGL already provides, and without putting the graphics card to work, either. Doubtless something on the level of Wolfenstein 3D could be made in this way, though, if that appealed to you.  Card Zero  (talk) 11:56, 13 September 2011 (UTC)[reply]
This is a link to a video of a 3D Yabasic game:
www.youtube.com/watch?v=3Lx0-scSwXk  — Preceding unsigned comment added by 213.107.74.132 (talk) 12:18, 13 September 2011 (UTC)[reply] 

What about a 2D QBasic game?--213.107.74.132 (talk) 12:20, 13 September 2011 (UTC)[reply]

You'd need to make (excuse the lack of simple language) filled shapes which scale down the positions of their vertexes as those vertexes
approach the vanishing point.

What on earth does that mean in Simple English?--213.107.74.132 (talk) 15:28, 13 September 2011 (UTC)[reply]

Which one of those words aren't in your dictionary? -- kainaw 15:49, 13 September 2011 (UTC)[reply]

Vertex. Sorry for taking a while to reply.--213.107.74.132 (talk) 16:05, 13 September 2011 (UTC)[reply]

In this case, vertex means corner. -- kainaw 16:08, 13 September 2011 (UTC)[reply]
See Vertex (computer graphics): "A vertex (plural vertices) in computer graphics is a data structure that describes a point in 2D or 3D space". If you actually want to produce 3D computer games, you'll have to learn a lot more than we can reasonably be expected to answer here (and a lot of it can't be explained in 'simple English' - you need to understand technical terms). There are many books available on the subject, as well as a vast amount of information online. I'd expect anyone computer-literate enough to program 3D games to also know how to use Google to find information online. Start searching, and learning... AndyTheGrump (talk) 16:13, 13 September 2011 (UTC)[reply]
213.107.74.132 - The level and type of your questions suggests that you are new to programming, or at least new to programming in Basic. May I suggest that you try to walk before you run ? Forget the 2D and 3D graphics, and start by programming a turn-based game that only requires text input from the user, and responds with text output or simple character graphics. Try writing a program to play hangman, Mastermind or a text-based version of tic-tac-toe, for example. Gandalf61 (talk) 16:21, 13 September 2011 (UTC)[reply]
Here [4] is the Yabasic triangle command. It takes six parameters, which are in three pairs, each having an x coordinate and a y coordinate. These are the positions of the three corners of the triangle. X and Y are of course only two dimensions, and in 3D, each corner of the triangle will also have a third coordinate, Z, which says how far away the corner is. Things which are further away look smaller. Therefore the Z coordinate should be used to control the amount of shrinking. This is done by moving the X and Y position of the corner closer to the middle of the screen, depending on the value of Z, before the X and Y are used in the triangle command.  Card Zero  (talk) 16:23, 13 September 2011 (UTC)[reply]
I know the Do your own homework rule, but are there any programming geeks here that know all the basic steps to make a 3D racing simlike Gran Turismo? BTW, I've made plenty of 2D games. And what about the red/blue glasses 3D?--213.107.74.132 (talk) 17:29, 13 September 2011 (UTC)[reply]
I think you might benefit from starting with XNA Racing Game. It is a complete racing game written in C# with XNA Game Studio, intended to run under Windows. Modify and learn, to your heart's content. Comet Tuttle (talk) 23:35, 13 September 2011 (UTC)[reply]
I said YaBasic or QBasic only. Thank's anyway. And what about the red/blue glasses 3D? BTW I saw a YaBasic 3D racing game at this link is:

http://www.youtube.com/watch?v=3Lx0-scSwXk

 — Preceding unsigned comment added by 213.107.74.132 (talk) 07:12, 14 September 2011 (UTC)[reply] 
Don't copy and paste the entire thread to the foot of the page to get attention! Adding to the existing thread, with more information about exactly what you want, would do the job better. The lack of replies is attributable to a lack of clarity. I doubt anybody here has made a computer game which displays anaglyph images. It would entail overlaying one version of the scene on top of a slightly shifted version, using a particular blending effect, which would take some experimentation. I see that the author of the game in the youtube video remarks that he also made an anaglyphic version, but can only provide the code for the normal version. I don't know how he would perform the blending of the second layer with the first. The PS2 has an alpha blend mode which can be turned on or off (here [5] somebody is using it in C), but I can't find any generic Yabasic command for changing blend mode.  Card Zero  (talk) 10:09, 15 September 2011 (UTC)[reply]
It would also help if the OP learns to format content properly on wikipedia. Don't leave a space before replies, they must have seen what it does and it's not desirable behaviour for general replied. Use WP:indenting and other formating as appropriate. BTW I actually do recall some 3D games with anaglyph support but they were commercial ones. Magic Carpet is the oldest I recall. Also for a long time, Nvidia supported anaglyph output via their stereo 3D drivers (which only had minimal support and which were barely advertised but were available and did work with a number of games although I never tried with anaglyph in particular). Then they started their new stereo 3D (3D vision) marketing where they concentrated on a few official support stereo 3D output modes. I'm not sure if they still supported anaglyph then. I know it was difficult, if even possible, to use the old style LCD shutter glasses for CRT monitors which plug in to the VGA port with their 3D Vision stuff. At the time ATI/AMD had no real stereo 3D support but with the recent revival of interest I believe this has changed but I'm not sure if they have anaglpyh output support. I seem to recall the unigine engine which is partially commercial but also available under GPL had stereo 3D including I think anaglpyh output Nil Einne (talk) 13:41, 15 September 2011 (UTC)[reply]
Some quick searching finds [6] and other results which suggests the 3D Vision still supports anaglyph (now that I think about it, I believe this was always the case, it was only the LCD shutter glasses which were supported in the older drivers but which they seemed to remove or hide in their newer 3D vision drivers). I've been unable to find out if ATI/AMD stereo 3D drivers support anaglyph output but I re-encountered IZ3D drivers [7] which are supposed to work with ATI/AMD and Nvidia chips and possibly even Intel ones and do support anaglyph output for free but only work with Direct3D stuff (not OpenGL). I seem to recall that it was generally easier to get DirectX games working then OpenGL with stereo 3D in general. In any case, I suggest if the OP really wants anaglpyh output it'll be easier to design their game to use Direct3D and design it with stereo 3D output in mind (e.g. all components should be 3D, there must be plenty of tutorials nowadays and the MTBS forums [8] is probably a good place to get ideas about what to avoid in a game that's going to be viewed in stereoscopic 3D) and allow the drivers to handle what the stereo 3D output mode is then to try to code anaglyph support from scratch. Alternatively using an engine like the unigine engine which supports anaglphy output. Nil Einne (talk) 13:59, 15 September 2011 (UTC)[reply]

PSVita[edit]

Can the PSVita run PS3 ports? Will they be like the PS3 games?--213.107.74.132 (talk) 09:11, 13 September 2011 (UTC)[reply]

See PlayStation Vita. This is not a "read the article for me because I'm far too lazy to do so myself" service. -- kainaw 14:34, 13 September 2011 (UTC)[reply]

PS3 HDD[edit]

I'm not sure if this is the right place, but if your PS3 does this, do you lose what's on the HDD?--213.107.74.132 (talk) 09:13, 13 September 2011 (UTC)[reply]

See Yellow light of death. The answer is very obvious. Hint: Hit control-F and type "hard drive". Even a hedgehog could find the answer in under 30 seconds. -- kainaw 14:37, 13 September 2011 (UTC)[reply]
Hedgehogs: the de facto Reference Desk benchmark species. Brammers (talk/c) 08:09, 14 September 2011 (UTC)[reply]
Smarter than the average erinaceid.
What about if the Yellow light problem is fixed on that particular PS3 by an indepenent console repair shop? Not a new PS3 (or refurb) but the same PS3 with the same HDD still intact?--213.107.74.132 (talk) 07:20, 14 September 2011 (UTC)[reply]

DDR2[edit]

how can DDR2 RAM does in windows vista and windows 7 need to run optimally?? — Preceding unsigned comment added by Sunita93 (talkcontribs) 09:14, 13 September 2011 (UTC)[reply]

Please see our article DDR2 SDRAM, and come back and ask a more detailed question if you need more specifics. Comet Tuttle (talk) 17:57, 13 September 2011 (UTC)[reply]

Computer Hardware[edit]

  1. why 4GB of RAM in windows xp professional sp3 can detect 3GB only??
  2. and why 500GB harddisk only show as 466GB??
  3. how DDR2 does in window vista and window 7 need to run optimally??
  4. where the amount of DDR2 memory has halves instead of double after installed a 1GB module with two 512MB modules??--Sunita93 (talk) 10:02, 13 September 2011 (UTC)[reply]
I have removed two duplicates of this question. --Kateshortforbob talk 10:09, 13 September 2011 (UTC)[reply]

Hard disk drive#Units of measuring capacity (see 2nd row of table, and multiply by 5) answers the question about HDD capacity . Mitch Ames (talk) 11:54, 13 September 2011 (UTC)[reply]

See 3 GB barrier for the first question. -- Finlay McWalterTalk 11:56, 13 September 2011 (UTC)[reply]

(edit conflict)

  1. This only happens in 32-bit Windows, but see 3 GB barrier for a full explanation.
  2. Instead of using powers of 1024, hard drive manufacturers use powers of 1000 and there's more on this on our article here. But basically a 500GB hard drive is sold as 500,000,000,000 bytes which is actually 465.66 GB.
  3. Technically they'll be fine with as little as 1GB, although by the time you've added AntiVirus software, realistically 2GB or more is a better number to have (that's a personal opinion though).
  4. What was the memory before? (how many did you have/what size each). Sorry if I've misunderstood, but from what you've described possibly your computer needs the memory to be installed in matching pairs and if they aren't matched then it won't use it at all.  ZX81  talk 12:00, 13 September 2011 (UTC)[reply]

For the record, this user asked the same questions a few threads above, and was shot down as a homework question. I guess adding an extra question mark avoids homework detection. Comet Tuttle (talk) 17:59, 13 September 2011 (UTC)[reply]

Ah, I didn't spot that, oops. Yes I agree though, the original one certainly looks like a homework question.  ZX81  talk 23:19, 13 September 2011 (UTC)[reply]
I think the bigger differences are the removal of the 'question' before the number and the rewording of the questions to make it sound like the OP was asking for themselves rather then about hypothetical users as well as changing stuff like 'explain in detail'. I actually have to give a tiny bit of credit to the OP, many homework question askers seem so lazy when they do repost, they just copy and paste their original question. Nil Einne (talk) 08:23, 14 September 2011 (UTC)[reply]

Mind Reading[edit]

A PS3 game, GT5, has mind reading software technology! Look at this link:

http://www.gtplanet.net/forum/showthread.php?p=5013041

Is this true? A PlayStation game can read your mind? That's a first!--213.107.74.132 (talk) 12:22, 13 September 2011 (UTC)[reply]

Sarcasm that obvious shouldn't be questioned. Doing so is nothing more than trolling because nobody who is capable of coming all the way here and asking a question is so mentally retarded that he or she is incapable of identifying that level of sarcasm. -- kainaw 14:30, 13 September 2011 (UTC)[reply]

javascript help: after copypasting data from excel/calc into a html textarea[edit]

i know i can use split() method to convert the data into an array but what is the separator? have tried \t \n \v and \r without success. probably need a combination of the above. this is to make the script work in ie too. — Preceding unsigned comment added by 59.189.221.245 (talk) 16:27, 13 September 2011 (UTC)[reply]

Whatever you put between the parenthesis is the delimiter. For example, to split a string called str on a tab, you'd use str.split("\t"); -- kainaw 16:41, 13 September 2011 (UTC)[reply]
I believe the OP might be asking what Excel uses as the separator. A column is separated by a horizontal tab ("\t"), while a row is separated by a Carriage return + Line feed. So a combination of:

myString.split("\t");

myString.split("\r\n");

TheGrimme (talk) 17:30, 13 September 2011 (UTC)[reply]

does calc use the same separator? — Preceding unsigned comment added by 203.116.187.1 (talk) 00:16, 14 September 2011 (UTC)[reply]
Not having Calc, it is difficult to say. You could write your code that works with Excel and test it out. Or, download Notepad++, paste in your data, and then select View -> Show Symbol -> Show white space. TheGrimme (talk) 16:09, 14 September 2011 (UTC)[reply]

sap mm[edit]

Hi, i like to know what is the best site for SAP MM,SD learning material, with some live examples.. — Preceding unsigned comment added by 166.249.129.220 (talk) 17:06, 13 September 2011 (UTC)[reply]

Downloading all Dropbox files and their revisions[edit]

How can I download all the files I have in Dropbox, plus their revisions? --Melab±1 21:35, 13 September 2011 (UTC)[reply]

This is urgent. --Melab±1 19:15, 14 September 2011 (UTC)[reply]
Sorry, but like it says at the top of the page It may take several days (to get a reply). I haven't used Dropbox in a while, but the last time I checked there wasn't any way built in to automatically extract all revisions, but this page on their website suggests to me they're all in a specific folder on your harddrive so I'd try taking a look there. If not (and you haven't already) I'd recommend contacting Dropbox and seeing what they say.  ZX81  talk 20:53, 14 September 2011 (UTC)[reply]

Broadband[edit]

I'm looking at broadband prices in the UK and I am a bit confused. Some of the prices for 'broadband only' are as low as £7 a month, but they all seem to assume that I have a BT phone line. I don't. So will the price in fact be £7 plus whatever a BT phone line costs, or is it inclusive? I'm completely clueless on this since I am currently with VirginMedia which comes through a coaxial cable. Basically I am looking for the absolutely cheapest "unlimited" download quota 'broadband only' package which is not VirginMedia (nothing wrong with them, just looking at other options) 82.43.90.142 (talk) 23:56, 13 September 2011 (UTC)[reply]

I don't know much about the UK broadband market but simple common sense tells me you will need a phone line for broadband only packages. If you don't currently have a fixed line phone line then yes, you should add the price for a phone line. (If you do currently have a phone line and have no plans to change the provider you should look for plans that you can use with your phone line. Again I don't know much about the UK situation but due to local loop unbundling and other factors it's possible some provider 'broadband only' plans won't be offered over your current phone line.) From [9] [10], it sounds like there's no legal requirement for naked DSL in the UK and it's barely available so the options for DSL without a phone line are rather limited. If you don't have and don't care at all about the phone line, I would suggest there's a fair chance looking at all inclusive plans would potentially lead to the cheapest deal. Nil Einne (talk) 06:53, 14 September 2011 (UTC)[reply]
That's correct. Many "broadband offers" assume that you already have a BT phone line. Some allow you to transfer the phone line rental from BT to another company. In cities, companies such as VirginMedia can deliver broadband through fibre and co-ax (but not in all streets), and in country areas where phone lines are poor, broadband is sometimes delivered via a microwave link. Another option is the use of mobile phone transmitters, but bandwidth and usage may be limited. Dbfirs 08:31, 14 September 2011 (UTC)[reply]
I recently changed my phone provider from BT to my ISP (and downgraded my internet package because I'm out a lot). Before the change I was paying £16 a month to my ISP and more than £15 a month to BT just to have the phone line (my last quarterly bill was over £50, of which just a £1 was for calls!!). Now I'm paying £7 a month to my ISP for internet and another £12 a month for the phone line. I pay £0 to BT. I'm not sure what would happen if I told my ISP I no longer wanted phone service. Astronaut (talk) 09:35, 14 September 2011 (UTC)[reply]
Your charges from BT would have been much lower if you hadn't used the phone line for internet access (though you probably had no alternative). BT don't allow you to join the "Light user" scheme if you have phone-line internet access, whatever the ISP. I think your ISP charges £12 just for providing the line (they probably pay most of that to BT for maintenance). Unfortunately, in most areas, only BT can physically provide a phone line, and this is often the only available way to receive broadband in non-fibre areas. Dbfirs 20:04, 14 September 2011 (UTC)[reply]