Wikipedia:Reference desk/Archives/Computing/2011 September 15

= September 15 =

Character entity reference for brackets
I'm trying to find the character entity reference for simple brackets [ and ] but cannot. List of XML and HTML character entity references doesn't have anything, and &#91 (the HTML entity, according to bracket) appears as the ampersand character, the number sign, and the number ninety-one, rather than as a bracket. I've also tried Google, and I found how to type an extensive list of references, including a long list of extended characters (e.g. &Otilde;), without using the ALT0___ code that Windows supplies, but it doesn't tell me how to get a bracket to appear. Any ideas? FYI, I'm trying to use a bracket as part of the anchor text for an external link in a citation: the original document has a typo in its title, and I want to include [ sic ], but that coding will cause the link itself to malfunction. Nyttend (talk) 01:14, 15 September 2011 (UTC)
 * If you chuck a semicolon (';') on the end of what you were using, it oughta work fine. Nevard (talk) 01:46, 15 September 2011 (UTC)
 * Testing. &#91;  &#93;  Does this work?  Nyttend (talk) 02:10, 15 September 2011 (UTC)
 * That's what I wanted; thanks. I knew that some types of references had the semicolon, including the non-breaking space, but bracket didn't include it, so I figured that it wasn't part of this reference.  Nyttend (talk) 02:11, 15 September 2011 (UTC)
 * They're all supposed to have a semicolon, as it signals the end of the entity. It's an easy thing to forget though. Reach Out to the Truth 23:52, 15 September 2011 (UTC)

Warm computers
At home, I use a nice laptop for everything. A problem, though, is the heat. I've got it attached to a cooling pad, so it's only 44 degrees celsius inside, well within the normal range. But after an hour or so on, it feels warm to the touch, and the whole machine seems to give off heat, making me warm and uncomfortable myself. It's OK for typing at my desk, I guess, but it's not pleasant if I want to use it in bed or on my lap.

Is there an alternative device that can be used for simple word processing and web-surfing that stays cooler? Do netbooks stay cool? What about iPads -- if one can type reasonably on them? -- Mwalcoff (talk) 02:27, 15 September 2011 (UTC)


 * I have a simple solution: point a fan at both you and the laptop. It should keep you both cool.  Another option is putting something between your lap and the laptop, like a pillow.  Or, best yet, do both. StuRat (talk) 04:01, 15 September 2011 (UTC)


 * Um, no. Don't rest a laptop on a pillow, because firstly this is likely to block the air vents, and secondly, pillows make good insulators - you risk overheating the laptop, and damaging it. I'd find something rigid and flat (a tray perhaps) to put the laptop on, allowing the air to circulate, and then rest that on a pillow. Unfortunately, computers aren't particularly efficient, and do produce a fair amount of heat - even a netbook can get quite warm. As for IPads, I'd think you'd find using them for word processing awkward, without a keyboard. AndyTheGrump (talk) 04:08, 15 September 2011 (UTC)


 * To clarify, the cooling pad would still be between the pillow and the laptop. I believe those are designed to be used on insulators like a wooden table, so an insulator like a pillow under it should be OK.  It should also keep the vents clear, by extending beyond them some distance. StuRat (talk) 04:12, 15 September 2011 (UTC)


 * Some netbooks stay quite cool. I don't use an iPad, but my GalaxyTab 7" also stays nice and cool. Typing on a tablet or a netbook can be an uncomfortable experience if you're used to touch-typing on a full-sized keyboard. It can be gotten used to, but you'll never achieve the same speeds you can achieve on a full-sized keyboard. APL (talk) 06:07, 15 September 2011 (UTC)


 * This news story made the rounds a year ago, about a boy who got permanent skin discoloration by "toasting" his leg with the laptop day after day. Comet Tuttle (talk) 22:20, 15 September 2011 (UTC)
 * I can't believe you chose the Daily Mail, of all things, as your source. But apparently this is real—it's called erythema ab igne (warning: mildly disturbing image). I may never put my laptop on my lap again. -- BenRG (talk) 00:21, 16 September 2011 (UTC)
 * I use a Rolodex® laptop stand, which not only allows good air circulation under the computer, but improves the keyboard angle.— Michael J 01:05, 16 September 2011 (UTC)

Cross platform shared libraries
I'm a fairly experienced C (not so much C++ but I can get by) programmer, and I suddenly find myself needing to build a shared library (for audio file conversion, but that's not important, I hope) which links to executables and runs under both Windows Vista/7 and Mac OS X Snow Leopard/Lion. Help! Are there any toolkits, templates, or other facilities which allow for production of such cross platform shared libraries with a minimum of overhead and a maximum of shared source code? Thanks. 70.91.171.54 (talk) 02:55, 15 September 2011 (UTC)
 * From what I gather, and some IBM people seem to agree (maybe a few tips you haven't heard of in there, and here), just stick to using IFDEF's. Nevard (talk) 06:22, 15 September 2011 (UTC)
 * Thanks. It could be a lot worse! 70.91.171.54 (talk) 21:13, 16 September 2011 (UTC)

How to you add support for new video formats to an HTML5-enabled broswer?
If you're developing a player for a new video format and you want to add support for the new format to HTML5-enabled browsers, is there a way you can package your player so that it can be added to and used in any browser that supports HTML5? Thanks. --71.185.166.51 (talk) 12:43, 15 September 2011 (UTC)


 * You want to develop your own file format? As in, replacing .mp4, .ogg, or .webm?.  Support for these are built in to the browser.  It would never be worth it to develop your own format.  See HTML5 video format support table. TheGrimme (talk) 18:02, 15 September 2011 (UTC)

Partition unallocated unformatted after merging
I freed 5gb from my c:\ and 5gb from my d:\ with disk management. then i used some other program to merge one of the 5gb free spaces with d:\. then, d:\ became unallocated unformatted and it could not be assigned any drive letters. Help! Thanks. 218.102.197.250 (talk) 13:09, 15 September 2011 (UTC)


 * What program are you using to do this ? You may need to define the format for that 10GB space, before it can be allocated a drive letter.  Also, are the C: and D: different physical disks ?  If so, I don't believe you can join them like that and assign a drive letter (there's no theoretical reason why this shouldn't work, but current software doesn't support it). StuRat (talk) 16:13, 15 September 2011 (UTC)


 * Thanks. They are in the same physical disk, and the two 5gb spaces were separate. But how do I define the format without erasing the disk? Thankyou. Again: now what was once D: is now unformatted and has no drive letter. 218.189.203.89 (talk) 07:23, 16 September 2011 (UTC)


 * What program are you using to do this ? StuRat (talk) 05:38, 17 September 2011 (UTC)

Excel 2007 - Numbers in Cells
I want to put a number in a cell in Excel 2007, and the number is, for example, 012345. The problem is, Excel is deleting the first 0, leaving me with 12345. This is a problem because many reference numbers begin with 0. How is it possible, in Excel 2007, to have the 0 included? I have looked around and only found information for Excel 2003, which all say 'delete the General', which is not possible in 2007. Cheers. -- KägeTorä - (影虎) (TALK) 13:22, 15 September 2011 (UTC)
 * When entering your ref number, put a single quote (') before it. Excel interprets that as being text rather then a number.  Astronaut (talk) 13:25, 15 September 2011 (UTC)
 * You can format the cell as text before entering the "number", or you can precede the "number" with an apostrophe when you enter it, e.g. '012345, or you can format the cell as custom format 000000 if it will always be 6 digits including the leading zero. There are other options, but that's a start. - David Biddulph (talk) 13:26, 15 September 2011 (UTC)
 * Thanks - I went with the 'formatting as text' option, and that worked perfectly. Cheers. -- KägeTorä - (影虎) (TALK) 13:32, 15 September 2011 (UTC)


 * Note that the disadvantage of storing a number as text is that you can no longer manipulate it as a number. So you couldn't easily have it add 1 to that number in another cell. In cases where you need it to look like a number but have leading zeroes, you should use a custom format. --Mr.98 (talk) 02:02, 16 September 2011 (UTC)


 * Do you want to check that, Mr98? Put the text string '012345 into cell A1, then put the formula =A1+1 in another cell.  Doesn't that add 1 to the number? Admittedly there are some functions which won't treat text as a number, but an arithmetic operation will convert from test to number.  Hence the trick of using a double unary minus (such as the formula =--A1) to convert from text or boolean to an equivalent number. - David Biddulph (talk) 17:24, 17 September 2011 (UTC)

help me in text speech
Hello i am new and i want to ask something.

My computer when i go to control panel and then click on text speech it brings to me one tab only what is Text To Speech.

My question is: is that's normal in other computers? or it is a virus?

i want answers please.

Note: please make answers with no bad words.

Thanks — Preceding unsigned comment added by Scorpion 1665 (talk • contribs) 14:09, 15 September 2011 (UTC)
 * Microsoft Speech API. It's normal and according to that article is part of every Windows OS since Windows 95 82.43.90.142 (talk) 14:18, 15 September 2011 (UTC)

Remote computer
I remember a while ago seeing sites which offered remote Windows (and linux) computers which you could connect to via the internet and use like remote desktop. Sort of like having a virtual machine but hosted on their server which would keep running even if your internet or power went down. I've tried searching but I can't it. Does anyone know the name of what I am talking about? 82.43.90.142 (talk) 14:16, 15 September 2011 (UTC)
 * Are you perhaps thinking of a Virtual private server    Nil Einne (talk) 14:33, 15 September 2011 (UTC)
 * Thanks, that's what I was thinking of. Seems very expensive though, would be cheaper to buy a second internet connection and host it myself using an old computer 82.43.90.142 (talk) 15:07, 15 September 2011 (UTC)

Capturing video from VCR
What equipment do i need to get the video from my vcr SCART socket? Do they make scart input capture hardware? I tried some SCART to video adaptor plugs, but they dont work (maybe theyre for input not output) I have a Belkin device but that has an Svideo connector and a phono connector. I do not have svideo connector on vcr.--92.28.81.140 (talk) 14:26, 15 September 2011 (UTC)
 * SCART is a bit nasty, because the exact signals in the connector can vary - potentially it can have RGB, S-Video, and Composite video, but it doesn't always have all of those. You can get SCART to S-Video adapters - is that what you've tried?  You can also get a cheap composite-to-s-video converter which you might be able to use with a SCART-to-composite adapter to convert the composite into an s-video signal you can use in your card.  There are capture cards that take RGB input that you could connect to a SCART output (Googling throws up ). --Colapeninsula (talk) 12:06, 16 September 2011 (UTC)

Re-installing Office 2007
I had Office 2007 installed on my PC which has since finally died. I want to reinstall it on my new PC but am worried that Microsoft Update will not recognise it as genuine software as it has already been installed and registered on a different PC. Is there any way round this problem so that I can install the Office suite and have it accepted by Microsoft?

Thanks in advance. Gurumaister (talk) 15:05, 15 September 2011 (UTC)


 * I've reinstalled office (2003, I don't know about 2007) in just this circumstance, without issue. In the off chance that it does object you can phone them, and they're usually pretty okay about this kind of thing. Their activation limits are mostly designed to stop someone installing the same licence on dozens (or sometimes hundreds or thousands) of PCs. Anyway, you've lost the old install, so there's nothing further to be lost from reinstalling. -- Finlay McWalterჷTalk 15:31, 15 September 2011 (UTC)

Many thanks, Finlay, I'll give it a try.Gurumaister (talk) 15:54, 15 September 2011 (UTC) PS: Happy 8th Wiki-birthday for yesterday  :))  Gurumaister (talk) 15:54, 15 September 2011 (UTC)


 * The installation and activation (registration) of Office 2007 depends on the license under which it was purchased. If the Office 2007 software suite was purchased either under Volume Licensing or as a Retail Full Packaged Product, you will have no problem activating it on a replacement computer. However, if it is an OEM disc, the software license lives and dies with the computer it came instlled on; you will have to buy a new license for a new computer. Rocketshiporion ♫ 19:45, 15 September 2011 (UTC)

iPhone
um... stupid question, I know, but how can I delete songs in my iPhone...........?--Irrational number (talk) 17:02, 15 September 2011 (UTC)


 * The only way I know is to connect it to your computer and, in iTunes, select the "Manually manage by device" option. Then, you can delete the songs on the device. -- k a i n a w &trade; 17:47, 15 September 2011 (UTC)

thank u!--Irrational number (talk) 18:37, 15 September 2011 (UTC)

Why does a WoW city appear to slow down around me, but not a real-world city?
If I'm in a major city in World of Warcraft, everything slows down around me.

However, I was in downtown Seoul in summer 2008, and everything kept going as fast as in any smaller city.

What causes this, and how do I fix it??? --129.130.99.18 (talk) 18:27, 15 September 2011 (UTC)


 * The more objects there are to draw, the longer it takes for your computer to draw them. Further, the more people there are to update, the longer it takes for a network-based game to update them. In the real world, we don't see the Universe hitting maximum update limitations for objects and characters. To fix your computer, get a better video card and faster Internet connection. -- k a i n a w &trade; 18:30, 15 September 2011 (UTC)


 * Reboot first, and don't run anything else at the same time as WoW. Most games also have options for slower computers.  You can turn off some less important objects, like maybe insects and smoke, and simplify others, so buildings don't need to draw each individual brick, for example.  Allowing fewer colors can also help, as can a lower frame rate, although that will make things look a bit "jumpy". StuRat (talk) 18:35, 15 September 2011 (UTC)

WoR (World of Reality) runs on faster servers than WoW. Looie496 (talk) 23:02, 15 September 2011 (UTC)


 * In point of fact time does run slightly slower in large cities because of additional gravitational time dilation from the higher concentration of mass. You don't notice this if you're in the city because your brain runs slower too, but if you were remote-controlling a robot avatar it would be noticeable—if the effect were a bit larger, at least. -- BenRG (talk) 00:43, 16 September 2011 (UTC)


 * I think your latter qualification is meant to actually just negate what you said before it, right? The dilation caused by the mass difference in a city is not likely to ever be measurable, is it, unless you change the laws of physics, right? --Mr.98 (talk) 01:43, 16 September 2011 (UTC)
 * Yes, I was being silly, but the effect might be detectable. The Pound–Rebka experiment detected a shift of one part in 4×1014 in 1959. This would be a shift of one part in 1020 or 1021 or so. -- BenRG (talk) 17:58, 16 September 2011 (UTC)


 * I appreciate that the OP is having a bit of a larf with the question, but there's an important insight to be had in the matter nonetheless. Modern games run the rendering engine asynchronously to the world simulation (physics, ai, etc.).  Objects fall, missiles fly, and robots think, at the same speed if you're in a flat boring plain (and getting a huge frame rate) or in a super-detailed city (and getting a really low frame rate). The renderer is like a stroboscope, sampling the underlying "reality" periodically and showing the results. Usually a "second" in the game takes a real-world second to transpire, but even that's a convenience for the human player; for non-realtime simulations (like simulations of weather or nuclear explosions) there's no such relationship, and a simulated second might take much longer or much shorter to actually happen in real time.  From the perspective of scripts running within the simulation, none of this is visible - they've got no exposure to the renderer or to "real" time. A simulation "second" is just N iterations through the think</tt> loop.  It sounds like the OP is thinking about the simulation hypothesis; if that were true, scripts (including ourselves) inside the simulation would perceive "time" as generated by the simulation, and any non-uniformities in the "real" computational cost and duration of generating that time would be wholly invisible to us.   Only slightly more prosaically, this brings us to a significant difference between how real physics works and the simulated physics of games or weather forecasts. In reality every massive particle interacts gravitationally with every other (in its light cone) and any photon can potentially interact with any particle in its light cone - that's a combinatorially vast number of interactions (which, if you were simulating reality perfectly, you'd have to calculate). Simulated physics is tractable because its designers try very hard to limit the interactions they model (e.g. if you fire a rocket down a passage in Quake, the game doesn't try to model the gravitational attraction between the rocket and other players' bodies or model the relativistic momentum transfer due to the light from the rocket's glowing exhaust hitting the walls). -- Finlay McWalterჷTalk 14:28, 16 September 2011 (UTC)

Use HP recovery disk on a Gateway computer?
I cannot find the recovery disk I created for my Gateway NV78 running Windows 7. I have an HP running the same version of windows. I have successfully saved all the files I want to an external hard drive using a Bootmed live CD. Is there some reason why I should not attempt to create a disk image and recovery disk from the HP and install it on the Gateway? μηδείς (talk) 19:41, 15 September 2011 (UTC)


 * It might be missing critical hardware drivers, it might be hardcoded to work only on that mobo. There's no rescue partition?  Gateway might send you a reinstall disc for a minimal fee. ¦ Reisio (talk) 21:14, 15 September 2011 (UTC)

From my experience recovery disks are specific to the manufacturer of the computer, sometimes even down to the exact make and model number of the original hardware, and will refuse to install on different hardware from another manufacturer. There is technically no reason why it shouldn't work, but it is prevented from doing so for licensing reasons. 82.43.90.142 (talk) 21:49, 15 September 2011 (UTC)


 * Sounds like what I expected. Computing is a hell of a lot more like a combination of alchemy and Freemasonry than chemistry or linguistics.  I have a system backup file on the PC I made in the spring.  Will have to see if that is rebootable, or, as I suspect, just a copy of the user files from that time.  Will also check with Gateway about the reinstall disk.  Thanks. μηδείς (talk) 22:07, 15 September 2011 (UTC)

Grabbing graphic images from within a PDF file
I want to grab graphic (raster) images from the PDF file they're embedded in, so as to maximize quality and prevent me from having to do things like screen captures in an effort to get the images alone. I only need to do this a few times for a PDF file, so I don't mind manually operating software that does this for one image at a time; I don't have to do some sort of batch-unrolling to save every single image. Does anyone have recommendations on Windows software to do this? I read List of PDF software but of course the article doesn't offer opinions on the software's suitability or quality. Comet Tuttle (talk) 22:16, 15 September 2011 (UTC)


 * You can easily do this with Acrobat proper (but it's not free). I'm almost certain you can do it with Inkscape (I'll go check as to how). -- Finlay McWalterჷTalk 22:51, 15 September 2011 (UTC)


 * Hmm, not trivially (not without essentially resampling the image), as far as I can tell. dumppdf.py says it should do it. -- Finlay McWalterჷTalk 22:57, 15 September 2011 (UTC)


 * Nah, forget that. -- Finlay McWalterჷTalk 23:27, 15 September 2011 (UTC)


 * Will this program meet your needs? Looie496 (talk) 22:59, 15 September 2011 (UTC)


 * Tried them; looked ideal but didn't end up working for the PDF I'm using. Comet Tuttle (talk) 04:46, 16 September 2011 (UTC)


 * Okay, this does work: <tt>pdfimages</tt> (which is part of Poppler and on Debian/Ubuntu system is in the poppler-utils package) does it easily and automatically. -- Finlay McWalterჷTalk 23:26, 15 September 2011 (UTC)


 * Um, just using Adobe Acrobat Reader (admittedly a 5 year old copy.. they may have removed this functionality) and using the 'Select tool' seems to work fine for me. I'm pretty sure older versions of FoxIt, a Windows PDF reader that's a lot less bad than Adobe, had this feature, as do many Linux and Mac OS X PDF readers. Obviously this is very manual indeed, but when couldn't life be easier? Nevard (talk) 23:41, 15 September 2011 (UTC)


 * This advice made me actually look around in my version of Reader (9.4.6) and I found the Snapshot tool, which worked for me! Thank you.  Comet Tuttle (talk) 04:46, 16 September 2011 (UTC)


 * Evince is even easier - just right-click the image and "Save Image As...". It's a Gnome app, but there is a Windows version too.  AJ  Cham  00:04, 16 September 2011 (UTC)


 * On the particular PDF I've been testing (a very primitive one that's just a single image alone in the PDF) neither evince nor okular offers a "save image as". I fear this functionality may be contingent on some weirdness in the formatting that I don't understand. -- Finlay McWalterჷTalk 00:15, 16 September 2011 (UTC)


 * How odd, looking a little deeper I see I too have some PDFs where the option is missing - they're all ones produced by Cairo (webpages I have 'printed' to a PDF file), whereas those produced from other software give me the option. AJ  Cham  00:26, 16 September 2011 (UTC)
 * PDF is a very complicated format. Not all "raster"-images are equal in a PDF document: some are JPEGs, some are embedded files, ... if the image is included as a embedded raster image, it's straightforward to extract the bitstream and recode it as a JPEG or image file.  But, the image could also be convoluted composition of clipping planes, vector graphic elements, and sub-images.  If the image is stored in that way, taking a screenshot is probably less lossy than trying to re-render and recomposite the image and then transcode it to an image format.  Ultimately, the way the imagery in the document is stored depends on what software and techniques were used to produce the PDF in the first place.  Nimur (talk) 02:42, 16 September 2011 (UTC)
 * In Acrobat Reader 8.1 it's:  advanced -> document_processing -> export_all_images     -- Finlay McWalterჷTalk 00:09, 16 September 2011 (UTC)


 * In Adobe Reader, you can usually select individual images and then copy and paste them into a paint program. --Mr.98 (talk) 01:45, 16 September 2011 (UTC)