Wikipedia:Reference desk/Archives/Computing/2010 February 7

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February 7

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MacBook volume control doesn't beep

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I have a MacBook running OS X 10.4. When I adjust the volume, it doesn't make the beeping sound. The volume itself is fine, it's just that the beeping has disappeared. Does anyone know of an explanation or remedy? --Lazar Taxon (talk) 00:26, 7 February 2010 (UTC)[reply]

I believe there's a setting somewhere ("System Preferences" > "Sound", perhaps?) that controls this. In any event, if you hold down shift while pressing the volume keys, it make a sound if it's set to be silent (and vice versa). Paul Stansifer 01:47, 7 February 2010 (UTC)[reply]
You learn something everyday. The option is System Preferences->Sound->Sound Effects->Play feedback when volume is changed. Rich(Contribs)/(Talk to me!) I can haz review plz? 14:03, 7 February 2010 (UTC)[reply]

How to record a streaming video from screen?

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Can anyone recommend some software to record a streaming video directly from my computer screen to my HD please? (Technically, I suppose I mean record it from the graphics card I think.) Ideally it should be able to decide what the window of the video is. I am experienced in recording many other streaming videos to my hard disk, and have looked at or used several different programmes. This video will not record by the previous methods I have used because the stream is encrypted. So what appears on the screen is what I want to record. I have tried lots of different things, done lots of Google searches already. So can anyone recommend some software please (not just do a Google search)? Thanks. 78.146.77.179 (talk) 00:56, 7 February 2010 (UTC)[reply]

VLC media player can record what's happening on the desktop (Media -> Open Capture Device -> select "Desktop" as the "capture mode") but I don't know if it can restrict itself to one window. Xenon54 / talk / 01:04, 7 February 2010 (UTC)[reply]
I tried it but I just got a .ps file which windows didnt know what to do with, and which I could not get to play. 89.242.43.246 (talk) 20:37, 7 February 2010 (UTC)[reply]
CamStudio --kv7sW9bIr8 (talk) 12:11, 7 February 2010 (UTC)[reply]
I've had more success with FRAPS than anything else. Comet Tuttle (talk) 15:13, 7 February 2010 (UTC)[reply]
The freeware version only records for 2 minutes, the other version costs more than I'd want to pay. 89.242.43.246 (talk) 20:40, 7 February 2010 (UTC)[reply]

I have spent all day looking, without reaching a conclusion. I have found "Video Capture Software" on download.com http://download.cnet.com/windows/video-capture-software/?tag=mncol%3Bsort&filter=licenseName%3D%22Free%22%7C&filterName=licenseName%3DFree%7C&rpp=10&sort=downloadCount+asc and http://all-streaming-media.com/record-video-from-screen/screen-capture-software.htm I think there is another collection of similar software somewhere, but the URL seems to be missing from my History. (Edit: the missing URL is http://www.videohelp.com/capture which has a lot of software listed somewhere on the site as well). The drawback of some of them described as freeware is that they have been made to only record two or five minutes. 89.242.43.246 (talk) 20:19, 7 February 2010 (UTC)[reply]

http://www.mplayerhq.hu/MPlayer/releases/win32/MPlayer-mingw32-1.0rc2.zip + http://www.mplayerhq.hu/MPlayer/releases/codecs/windows-essential-20071007.zip (goes into 'codec/s' dir of former). mplayer -playlist -dumpstream URIhere -dumpfile foo (occasionally you will not want -playlist). VLC can probably do this almost as well, though. ¦ Reisio (talk) 06:11, 8 February 2010 (UTC)[reply]

Have you seen our article, List of screencasting software? Comet Tuttle (talk) 19:10, 9 February 2010 (UTC)[reply]

C99 and // comments after #include

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In syntax highlighting for C code, Kate doesn't format comments that start with a double slash as comments if the line they're on starts with a #include. Is this a bug in the syntax highlighting, or does C99 actually disallow double-slash comments on the same lines as #includes? (GCC says C90 doesn't allow double-slash comments at all, which is why I ask about C99 specifically.) If the latter, what other preprocessing directives are affected? NeonMerlin 01:45, 7 February 2010 (UTC)[reply]

It may have to do with that comments aren't recognized within < > so one can have odd names in there, I haven't the foggiest why one would want to do that. Perhaps the editor treats such preprocessor lines specially as they can break all sorts of rules, as in fact can the source code but if one starts defining a macro that substitutes to a curly bracket one deserves the pain one gets. Dmcq (talk) 10:03, 7 February 2010 (UTC)[reply]
FYI emacs, enscript, and gedit work as you expect, and Mediawiki's "source" extension works like Kate. -- Finlay McWalterTalk 16:17, 7 February 2010 (UTC)[reply]
There is something wrong with the highlighting rules. And yes, it's the same in GeSHi:
// A comment looks like this
#include <stdio.h> // Not this

decltype (talk) 18:23, 9 February 2010 (UTC)[reply]

Word 2007 Table Alignment

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Hello. I've been trying to figure this problem out for some time, and I can't even bring anything up on Google! I have Microsoft Word 2007, and I've been trying to make single-cell tables. The thing is, the alignment I keep choosing won't save: I want everything to align in the center and to the left, but when I save and exit the document, it doesn't stay the way I want it to. When I reopen the document, the alignment is always completely centered! —Preceding unsigned comment added by 69.16.91.90 (talk) 05:43, 7 February 2010 (UTC)[reply]

You can only align one way, either right,left, centered, or justified...Smallman12q (talk) 17:08, 7 February 2010 (UTC)[reply]
By "center" he probably is referring to vertical alignment: middle. This can indeed be combined with horizontal alignment left. (I am very annoyed about the Tab key that does no longer set focus to the next control.) --Andreas Rejbrand (talk) 09:19, 8 February 2010 (UTC)[reply]

Powering Computer during powercut - was Question

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In a few weeks there's going to be a 10 hour power-cut. I want to use my desktop computer during this time, however obviously I can't because of the power-cut. I can't afford a uninterruptible power supply or a electrical generator, and I don't have a laptop. What solutions are available that might enable me to use my computer? I have access to car batteries and wires and stuff if that could help building a homemade UPS. —Preceding unsigned comment added by 82.43.89.14 (talk) 13:56, 7 February 2010 (UTC)[reply]

You probably want an inverter. You will almost certainly need a few batteries for 10 hours, however. Your average car battery is (I think) 40amp-hours{{fact}}. That provides 480Wh. A middle of the range HP desktop has a 220W power supply (that's ignoring the display), so each battery will last maybe two and a bit hours, although someone more current (pun not intended) on the maths involved should probably check this. --Rich(Contribs)/(Talk to me!) I can haz review plz? 14:33, 7 February 2010 (UTC)[reply]
(ec) The easiest solution would be to put you computer in your car and drive to where there isn't a power cut. Note that if you decide to buy a 12V to mains adaptor, you'll need to figure the load carefully, a PC and monitor can consume a surprising amount of power and your adaptor may not have the rating to cope and/or your battery may expire before the cut ends. Also if you are net connecting, you'll also need to power your modem. -- SGBailey - not signed in 82.45.16.156 (talk) 14:39, 7 February 2010 (UTC)[reply]
or plug an inverter into your car's cigarette lighter and leave the engine running!
Car battery inverters typically supply between 150 and 300W - so be careful to not overload it.87.102.67.84 (talk) 15:04, 7 February 2010 (UTC)[reply]
This page covers inverters and generators http://home.howstuffworks.com/home-improvement/household-safety/security/emergency-power3.htm (if you decide to use multiple 12V batteries connect them in parallel !)
You can rent generators (but obviously they might be in short supply during a power cut)87.102.67.84 (talk) 15:02, 7 February 2010 (UTC)[reply]
You should also be aware that you probably won't have internet access during the powercut.Smallman12q (talk) 17:10, 7 February 2010 (UTC)[reply]
Buy a cheap used UPS without a battery (this is much cheaper than an inverter). Make sure it's rated for the power draw of your computer + monitor + router and dsl/cable modem. Then hook it up to a car battery. Do the math to see how long it'll last though. Ariel. (talk) 05:54, 8 February 2010 (UTC)[reply]
You should not use car batteries for this since the deep discharge will damage them. Use marine batteries, the type intended for running outboard electric motors, or golf cart batteries, which amount to the same thing. They are formulated differently so they can withstand repeated discharge. 66.127.55.192 (talk) 10:59, 10 February 2010 (UTC)[reply]

Would a stripped-down Python equal Basic?

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If you ignored the Python commands not present in your average BASIC, would programming with whats left be roughly equivalent to programming with BASIC? 89.242.43.246 (talk) 14:39, 7 February 2010 (UTC)[reply]

Yes, ignoring syntax and required formatting, and differences in reserved words. A good page is Comparison of programming languages note BASIC is an imperative, procedural language so any language that uses an imperative style (this means that commands are executed as they are listed) which also can implement procedures (in python you would use functions I think) can be programmed in the same style as you would in basic.
Or to put it another way making a utility that converts basic to python code would be do-able easily.87.102.67.84 (talk) 15:11, 7 February 2010 (UTC)[reply]
Except there's no GOTO in python - but you can live without that ? 87.102.67.84 (talk) 15:13, 7 February 2010 (UTC)[reply]
(By the way if you are looking for alternatives to basic - my suggestion for your first step would be to continue programming in basic - but practice writing proceedural code that never uses goto - repeat/until and do/while are usual replacements - it's sometimes a pain when a simple goto seems obvious - but worth learning for when you don't have a goto (as in many newer languages). If you were already programming without ever using goto then well done!)87.102.67.84 (talk) 15:17, 7 February 2010 (UTC)[reply]
Thanks, I have long been aware that goto was not approved of, and have not used it for years and years. I don't suppose theres any sort of tutorial or list of BASIC-like commands that would make the transition from BASIC to Python easier? Or even some patch or variant that would hide al the non-BASIC stuff out of the way? I've long though that programs of all types should have a built-in choise of Beginner, Intermediate, or Advanced modes that would make beginning to use them less daunting. 89.242.43.246 (talk) 19:36, 7 February 2010 (UTC)[reply]
If you ever used BBC Basic you're in luck BBC basic / pythton differences via roscidus.com - if not you'll still recognise a lot of the basic. (http://docs.python.org/ is the place to start in general) There are some VisualBasic to Python converters out there which might help in learning about equivalent python code.
No idea about a reduced version. Haven't heard of one.87.102.67.84 (talk) 20:40, 7 February 2010 (UTC)[reply]
Thanks, I've just read that. Pity Python wasnt called PYBasic - I bet it would be even more popular. 89.242.43.246 (talk) 22:12, 7 February 2010 (UTC)[reply]
Not everyone thinks BASIC is a good thing. Edsger Dijkstra, for example, had a rather low opinion of it. Others may not be so radical (I can't be, for instance, because I learned BASIC first!), but I doubt that Python would benefit from association with it. --Tardis (talk) 18:24, 8 February 2010 (UTC)[reply]
(edit conflict) I suppose so, more or less, although Python's for statement is technically a foreach, which is more general than BASIC's for loop. This is not a specific property of Pyhton - you can reduce almost any imperative programming language to BASIC + other stuff. But why would you want to write Python as if it were BASIC ? Gandalf61 (talk) 15:22, 7 February 2010 (UTC)[reply]

how does the size of an HP pavilion dv 9700 17" compare with an Apple MacBook 17"?

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I know the aspect ratio might be different, so I was wondering how the screen size of an HP Pavilion DV 9700 17" compares, in terms of actual square centimeters, with the screen size of a MacBook 17". Thanks 92.230.233.5 (talk) 16:56, 7 February 2010 (UTC)[reply]

The apple mac book pro is 1680 x 1050 ( WSXGA+ ) [1], the apple mac book is 1280x800 Wide XGA [2] , the HP is 1,680 x 1,050 [3]
All have aspect ration 1.6:1 - the same then.87.102.67.84 (talk) 17:07, 7 February 2010 (UTC)[reply]
The 17" MacBook Pro is actually 1920 x 1200. 209.94.102.85 (talk) 18:04, 12 February 2010 (UTC)[reply]

Wikitable

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If, when I start making a table, I put class="wikitable", I get:

class="wikitable"

Which is nice.

If I put "border="1" instead, I get

Border = "1"

Which is nasty nasty.

However, class="wikitable" does not work when I try it on a table on this wiki. I assume I have to twiddle some settings somewhere to get the wikitable? I've seen it used on other wikis, after all. How do I get the wikitable? Be aware that my technical knowledge is very limited. Cheers in advance! Vimescarrot (talk) 17:31, 7 February 2010 (UTC)[reply]

Oh, and if you think I should be asking this somewhere else, feel free to point me in the right direction. Vimescarrot (talk) 17:32, 7 February 2010 (UTC)[reply]

Classes do not work by magic voodoo. Neither your browser nor the wiki software simply takes the word "wikitable" and intuits how you want the table to display. Wikitables look like that because of rules in a CSS stylesheet (in this case Mediawiki:Common.css) which tell your browser to apply various styles to tables with the "wikitable" class, and to elements of those tables. The relevant rules are as follows:
table.wikitable {
    margin: 1em 1em 1em 0;
    background: #f9f9f9;
    border: 1px #aaa solid;
    border-collapse: collapse;
}
.wikitable th, .wikitable td {
    border: 1px #aaa solid;
    padding: 0.2em;
}
.wikitable th {
    background: #f2f2f2;
    text-align: center;
}
.wikitable caption {
    font-weight: bold;
}
So to make a table display like a wikitable without using CSS, you'd have to style the table with {|style="margin: 1em 1em 1em 0; background: #f9f9f9; border: 1px #aaa solid; border-collapse: collapse;", and similarly add the appropriate styles for each <th>, <td> and <caption> within the table. Algebraist 17:46, 7 February 2010 (UTC)[reply]
Nice, thanks. So if I get one of the admins to put that in MediaWiki:Common.css, it'll apply across the wiki? Here's hoping they still have active admins...Cheers! Vimescarrot (talk) 19:31, 7 February 2010 (UTC)[reply]

Building netbooks

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Can u build your own notebook. Like, 4 instance, an Acer Aspire One. —Preceding unsigned comment added by 68.34.181.72 (talk) 18:47, 7 February 2010 (UTC)[reply]

yes. [4] see also Barebook 87.102.67.84 (talk) 19:07, 7 February 2010 (UTC)[reply]

Does anyone know how to record a programme from the ITV Player? Only for my own personal use. It is only viewable to people in the UK. I think the most likely route is "video capture" from the screen, but the easier to use freeware can only record for 2 or 5 minutes, and I have not yet got any unrestricted freeware to work. See also the querstion "How to record a streaming video from screen?" above. Thanks. 89.242.43.246 (talk) 20:26, 7 February 2010 (UTC)[reply]

get_iplayer, which is primarily targetted at the BBC's iPlayer site, has at various times also been able to download and save content from 4OD and ITV. In the case of 4OD they got into something of an arms race with the 4OD people, and I don't think it supports 4OD any more. Equally it used to be able to work on ITV (per this post), until a redesign. You might be best asking on the get-iplayer forums, incase someone has it working there again. -- Finlay McWalterTalk 20:31, 7 February 2010 (UTC)[reply]
I've already got get_iplayer and asked on the forums, and it does not work with the ITV Player any more. 89.242.43.246 (talk) 21:29, 7 February 2010 (UTC)[reply]

I think it probably something to do with RTMP or RTMPE although I'm only guessing. 89.242.43.246 (talk) 01:24, 8 February 2010 (UTC)[reply]

Personal wiki recommendations

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Can anyone recommend a free personal wiki? One I can run on my PC (WinXP) without having to have a server or anything like that, and preferably not too dissimilar in how you make links etc to the thing Wikipedia works on. I do tend to regard computers as "black boxes" so if you can avoid mentioning pythons and the like I'll be more likely to understand what you are saying! Thanks, DuncanHill (talk) 23:31, 7 February 2010 (UTC)[reply]

You might want to try tiddlywiki, I use it for organising information related to my undergraduate research project. It has very nice interface, active development, easy upgrades, a backup system, similar markup to Wikipedia and plenty of plugins if it doesn't do what you want it to out of the box. 131.111.185.75 (talk) 00:20, 8 February 2010 (UTC)[reply]
Thank you, that seems to be what I'm looking for :) DuncanHill (talk) 01:39, 8 February 2010 (UTC)[reply]
You may as well just use mediawiki. It needs a database (you'll have to install mysql) but does everything that you're used to. There are some other wikis like moinmoin or tiddlywiki that may be a little simpler to configure but nowhere near as featureful. 66.127.55.192 (talk) 02:19, 8 February 2010 (UTC)[reply]
You can use it with postgres as well! Marnanel (talk) 02:29, 8 February 2010 (UTC)[reply]
I just read the installation instructions for mediawiki and I do not understand them at all. It seems to need lots of other stuff, not just downloading it and starying it up. If there was a way to use it on my pc I would, but I can't see or understand how. DuncanHill (talk) 02:47, 8 February 2010 (UTC)[reply]
You could try MoWeS; it sets up everything you need for MediaWiki automatically, just make sure to select MediaWiki in the packages selection download page —Preceding unsigned comment added by Kv7sW9bIr8 (talkcontribs) 12:37, 8 February 2010 (UTC)[reply]
Would I be able to use that (once installed) without being connected to the internet? DuncanHill (talk) 21:34, 8 February 2010 (UTC)[reply]
Yes, you could use it offline. Thanks, gENIUS101 21:55, 8 February 2010 (UTC)[reply]
Alternatively, find a webhost (there are free ones available on google, I use x10hosting.com) with an automated mediawiki installer. The one I've encountered is softaculus. Simply load it up through the cpanel/other admin interface, tell it to install mediawiki, and follow the prompts. It'll sort all the complex stuff for you, and the default options are usually ok. Rich(Contribs)/(Talk to me!) I can haz review plz? 16:00, 8 February 2010 (UTC)[reply]
I'm really looking for something that doesn't need me to be connected to the internet - it's just for personal use as an aid to research and writing, not for something I want published online (and anyway, it costs money to be online!) DuncanHill (talk) 21:34, 8 February 2010 (UTC)[reply]
Why do you want a wiki? Maybe you're better off just using a text editor, along with a version control system like git. In fact there is even a wiki called "gitit" that uses git as its backend. 66.127.55.192 (talk) 11:09, 9 February 2010 (UTC)[reply]

Check out the personal wiki article, it lists lots of wiki-like software that doesn't need servers or complicated set-up —Preceding unsigned comment added by 82.43.89.90 (talk) 14:01, 9 February 2010 (UTC)[reply]