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April 23

Laptop problems

I have a laptop running on six years old that appears to be slowly failing. What triggered this post was a problem that I've had in the past, but after a reboot I've been fine. Before I begin, I must admit that I do keep my computer on 24/7 and reboot it when it gets to a point of uptime-induced instability, but this is now happening even after a reboot.

I went to watch an MKV H264 480p file, but when I do, CPU usage goes through the roof (80%+) and the video desyncs from the audio. After a few days of uptime, but sometimes soon after a reboot, the audio will fail. Programs that rely on it working fail (Winamp reports "Bad DirectSound driver", Media Player Classic gives an AudioSwitcher:Out pin failure [I think that's what it says]). Similarly, CPU usage recently tends to go high for programs that aren't supposed to be using that much CPU, and sometimes to the point of crackling audio or lagging mice (I physically move the mouse, it doesn't move on the screen for 500ms-1000ms), which tends to be at 90%+. It gets to the point where I keep Javascript disabled for smooth browsing on sites that use it.

Even at idle, CPU usage is up around 40% and Task Manager lists items that should not be using that much CPU (e.g. Taskman itself using ~30%) and windows are lagging when I switch between them (e.g. between Firefox at this editing box and Taskman, elements from Taskman are left behind as it "unloads from view" [yeah, not the right term]). Printscreening and using scrollbars in Paint (mspaint) does not scroll smoothly anymore, but redraws lines so slowly you can see it as it moves to the new window position.

As I speak I can't play songs in Winamp without it causing 90%+ CPU usage, nor emulate (yes, I own them) at 60 fps; I get <10 fps in the emulators I try. It's so bad, I don't even want to try a resource-taxing game like The Sims or Portal. It's taking many times longer for programs to load than it usually does.

Specs:

- P4 2 GHz dual core (the dual core, in my first few years experience with this laptop, limits the high CPU usage to one core, but the 90%+ recent usage seems to not)
- 1 GB RAM
- 85 GB internal HD, two external worth 2.72 TB and 931 GB (yes, deceptive metric system advertising)
- GeForce Go 7300
- Sigmatel integrated audio

What I would like to know is if anyone can discern what is causing my problems. I understand it is incredibly difficult to do so using third-party information (e.g. you can't try it yourself, I'm telling you). Which component of my PC is likely to be causing these problems?

As an aside, while typing this post, I noticed my keyboard's repeat rate appears to have gone down. I went to the Control Panel's keyboard config, but it's up as far as it can go. It was fine before the most recent reboot. The aforementioned problems are even causing my keyboard input to lag as I mentioned my mouse does. -- Tohler (talk) 00:03, 23 April 2012 (UTC)

After a failed shutdown, I thought "I wonder what process is holding the shutdown" and became frustrated enough that I began killing them. For a little while (15 minutes), everything worked fine again (yes, even with a failed shutdown) except for Firefox 3 couldn't load pages (my primary is 1.5; yes I'm extremely outdated). A little more insight into the situation... -- Tohler (talk) 00:40, 23 April 2012 (UTC)

Yes very difficult to discern, but it seems to me that Windows (I presume XP?) needs a complete reinstall. What I mean is: backup, format, install from scratch. After six years of usage there could be any amount of spyware/clutter/etc. floating around and this is even with a decent antivirus installed. There may be other ways to fix it but these could be long-winded. If the laptop still displays strange behaviour after a fresh install, then you can look at trouble-shooting hardware issues. Sandman30s (talk) 12:54, 23 April 2012 (UTC)

^ I agree, most Windows installs just get more and more crufted over time, eventually forcing a reinstall. You could switch to Linux, too. :) If you decide it's a hardware issue, after six years you should probably just replace it — you can probably get a new laptop with more than twice the processing power and probably quadruple the RAM for around $350 (at least in the USA), which is probably less than half what you paid for this machine six years ago — one perk of living in the future. ¦ Reisio (talk) 15:39, 23 April 2012 (UTC)

If you want to continue with your current laptop, the complete Windows reinstall is the way to go. Small improvements that would work out cheaper than a new laptop are more memory and a bigger hard drive, but you might struggle to find compatible components at the best prices and hardware limitations might restrict how far you can upgrade. However, that doesn't help improve the CPU speed and screen resolution, which is fixed for almost all laptops, and I wouldn't mind guessing the battery life is almost zero if you dare unplug it from the mains power. Astronaut (talk) 16:22, 23 April 2012 (UTC)

Do you have reason to believe H.264 480P will work on your computer? If your computer is really dual core pentium-D it may, although I wouldn't guarantee it. It also depend on the profile of the encoded video of course. If its single core with hyperthreading (if it's called a Pentium 4 it's probably the later since NetBurst were always officially called Pentium-D) there's a chance it won't. You can try CoreAVC and see if it improves matters or you may just have to upgrade. In any case you should expect high CPU usage. With a Very weak CPU and GPU, the inability to run even old games like Portal at 60fps is hardly surprising. Nil Einne (talk)

I've made h.264 work up to 1024p on my 2004 single-core p4. Required the following setup if I can remember correctly: Nvidia pure video (not needed any more), Sonic HD Decoder, latest CCCP drivers and the only player that could play it reliably was Media Player Classic. I even managed to play raw bluray files via this setup, and bluray discs via an older version of PowerDVD (I think 7.3) with a HD playback kit. I think at the time I had a 6000-series nvidia card in it. Of course currently there are tons of software and media players that can play MKV but you'd be surprised at the power of computers of ten years ago and how much can be squeezed out of them. Sandman30s (talk) 19:37, 23 April 2012 (UTC)

- Sandman & Resio: Yes, I am running XP. I have actually thought of multibooting with Ubuntu the next time I get a new computer. What distro do you use? Similarly, do you multiboot, and if so, what steps/programs do you recommend? I have no experience multibooting in the past. I plan on multibooting with XP, Vista/7, and Ubuntu; I'd also enjoy running 98 or 95 non-VM for the nostalgic factor but I'm wondering if the differing filesystems will cause a problem.

- Nil Einne: Yes. In the past I have been able to run 480p with no trouble. Even 720p worked fine most of the time. When I mentioned I didn't want to run Portal or The Sims, what I meant was that I didn't want to run items with even higher requirements given that light usage as described caused all these problems.

- Astronaut: By resolution do you mean display resolution? I'm running 1680x1050 with an external monitor. You are semi-correct about the battery - it can't hold a charge for as long/as much of a charge as it used to.

- Six years ago I bought my laptop for my college career. Today I have no need for mobility with my computer. With today's technology, is there a large difference between a tower and a laptop? (I do have a tower, but it's even older - 2003) However, I would be interested in a $350 laptop for those instances where I may be required to travel for my job; do you recommend a specific brand/company that would give said specs/price?

- Do you guys recommend the buying of individual parts/self-assembly or the buying from a company like Dell (where my tower and laptop came from)? Do you recommend any other companies?

- One thing I would like to do is keep the data that is currently on my hard drive. If I get a new system with a new HD and the OS installed on that, would it be wise to hook my current-laptop HD up as a secondary HD, or copy the data over to the new one?

- One minor unrelated question that I don't want to start a whole new question for. For example, on the TV Tropes site, when describing a fantasy TV show with doppelgangers/fakes, I see phrases like "Real!Joe" and "Fake!Joe". It's quite obvious the form is (descriptor)+(name), but why is the exclamation mark used? Where did this "tradition" come about and why is it used in place of something like a dash ("Real-Joe")?

Thank you all for your help! -- Tohler (talk) 20:14, 23 April 2012 (UTC)

wrong fonts?

why my computer is not able to display some languages? like in this example (look at double squares):

search • suchen • rechercher • zoeken • ricerca • szukaj • buscar • поиск • 検索 • busca • sök • 搜尋 • tìm kiếm • пошук • cerca • søk • haku • hledání • keresés • 찾기 • cari • ara • جستجو • căutare • بحث • hľadať • søg • serĉu • претрага • paieška • poišči • cari • חיפוש • търсене • іздеу • bilatu • suk • bilnga • traži • खोजें

Thanks, John — Preceding unsigned comment added by 69.86.231.47 (talk) 01:32, 23 April 2012 (UTC)

I think that's more of an issue with your browser, rather than your computer in general. Are you using Internet Explorer? See the following page for more information: http://support.microsoft.com/kb/928847. I use Firefox and those characters display without any problems. This page should be in UTF-8, which supports those characters. If you set the font manually, it should display in your browser, like this:

search • suchen • rechercher • zoeken • ricerca • szukaj • buscar • поиск • 検索 • busca • sök • 搜尋 • tìm kiếm • пошук • cerca • søk • haku • hledání • keresés • 찾기 • cari • ara • جستجو • căutare • بحث • hľadať • søg • serĉu • претрага • paieška • poišči • cari • חיפוש • търсене • іздеу • bilatu • suk • bilnga • traži • खोजें

—Best Dog Ever (talk) 02:20, 23 April 2012 (UTC)

This image shows what it looks like in Firefox 3.0. It also shows how to get to Firefox 3.0's character encoding selecter. -- Tohler (talk) 04:58, 23 April 2012 (UTC)

Depending on which squares you're seeing, you may simply be missing required fonts. http://www.alanwood.net/unicode/fonts.html ¦ Reisio (talk) 15:41, 23 April 2012 (UTC)

I have no squares; these all look fine, which sugests that, yes, you are simply lacking the required font sets. Mingmingla (talk) 22:36, 26 April 2012 (UTC)

Name for digital projection concept ?

If I project an image in such a way that it is foreshortened, this results in multiple pixels on the original mapping to the same pixel in the projection. This produces the following ugly image when I project a grid:

If, however, I don't project the background pixels, this avoids overwriting any foreground pixels, producing a much better result:

So, is there a term for this problem, and/or this solution ? StuRat (talk) 05:56, 23 April 2012 (UTC)

The problem is a kind of aliasing artifact. The solution in general is to use spatial anti-aliasing techniques. Looie496 (talk) 06:41, 23 April 2012 (UTC)

Thanks. Any name for this specific technique, or the related technique of projecting colors closer to the background color first ? StuRat (talk) 14:10, 23 April 2012 (UTC)

You just worked around the aliasing and moire, by intentionally not drawing the entire image at the same time. This worked for simple line art, but the technique does not work in general. I'm not aware of a name, other than line drawing with a paint order. Several algorithms specify a paint order, like any z-buffering technique or the painter's algorithm, but those are intended to solve clipping problems, not antialiasing. If you want to get this working in the general case, you do need to actually use spatial antialiasing. There are many names for specific implementations of antialiasing filters. Nimur (talk) 15:03, 23 April 2012 (UTC)

I'm more interested in high-speed rendering of wireframe animations than slow, shaded image rendering, so this method works best for me. StuRat (talk) 18:39, 23 April 2012 (UTC)

If your wireframe animations contain high spatial frequencies, they will also alias. You got lucky this time. If you are using hardware acceleration to render, (e.g., OpenGL running on almost any reasonable GPU), there is no speed-penalty for enabling antialiasing, using e.g. glHint(GL_LINE_SMOOTH_HINT, GL_NICEST). Your mileage will vary, depending on your graphics driver; of course there are better ways to antialias in special cases. (With due respect, StuRat, I'm really expecting you to come back and tell me you're using FORTRAN code to software-render pixel-values into a text-document, which you convert to GIF using a Windows program; in that case, you're fooling yourself if you think antialiasing has any performance impact on your workflow). Nimur (talk) 18:46, 23 April 2012 (UTC)

Almost. I'm using a FORTRAN program to create PPM panes, which are then stitched into an animated GIF using ImageMagick. Each pane takes about 7.5 milliseconds to render, at 400×400 resolution. That seems plenty quick, to me. I have a low-end CPU (Pentium 4, 2.8GHz, running Windows XP SP3), and hardware acceleration is not available. StuRat (talk) 18:56, 23 April 2012 (UTC)

Here's a wireframe animation I created which requires red-blue 3D glasses:

My 3D animated grid (2 corners appear to peel up). For best results, pick on it, then select full resolution, below.

I intend to add more frames to it, later. I've also created shaded animations, where I render the shading first, then add a grid on top:

Fountain animation.

Morphing 3D graph.

19:10, 23 April 2012 (UTC)

StuRat, these are very nice animated plots, but you're really going to a lot of effort because you're using the wrong tools for the job. For example, GNU Octave (which is totally free software, and runs on Windows), can generate 3D plots using the mesh() functions. In fact, you can plot many different types of wireframe and smooth surfaces; you can perform animations, output as discrete image frames, or compress as a movie file, all using free and open-source software that even runs on Windows. A task that will take you hours of FORTRAN programming can be accomplished in mere seconds if you select a reasonable toolkit. If you're just doing this for the joy of re-implementing the mathematics of elementary shaders and lighting and projection geometry, then your efforts are not in vain (but, you should spend the effort to learn how to do it right - antialias!). If you're simply using your program as a means to generate nice animations, you should reconsider your toolkit. Your Pentium 4 is a fine processor. It can easily handle these sorts of calculations. Almost certainly, your system has some capability to hardware-accelerate OpenGL, even if you lack a discrete graphics daughtercard. Almost every Pentium-class system has a simple GPU integrated into the system. If your Pentium 4 is outputting to a monitor in any way at all, then it's a sure bet that your motherboard has one of these Intel chipsets, which includes one of these graphics units, which support at least OpenGL 1.4 - which contains an advanced feature set far beyond you need for simple surface rendering, wireframe animations, and other graphics and animation. Sure, it'll cough and stutter when you try to run the latest and greatest games, but accelerating your 400x400 pixel wireframe renders will be no problem. Nimur (talk) 23:16, 23 April 2012 (UTC)

This is a hobby of mine. Your comment comes across a bit like telling someone who likes to garden that they can just get flowers already grown, so they should stop wasting their time. It's not just about the results, it's about doing it for myself. I also disagree with the idea that there is only one right way to do things. If that was the case, we wouldn't have wire frame, surfaced, and solid models. The reality is that different methods are better for different purposes. StuRat (talk) 03:17, 24 April 2012 (UTC)

If your hobby was painting model airplanes, and you were using water instead of paint thinner to clean the brushes, I'd tell you the same thing: you're using the wrong tool for the job. There are many ways to clean a paintbrush, but one works better. Similarly, you can render images in n different ways, but some methods work better. I can appreciate your goal; I also enjoy hobby programming and working with 3D images; but I think you're expending a lot of unnecessary effort. If you make the effort to learn the most powerful tools available to you, you will be able to produce more results in the same amount of time. Even if you're dead-set on using a particular programming language and software toolchain, you should at least ramp up on the mathematical tools of image processing: aliasing is important to understand because it will affect your renders. You can ignore it for now, as you have done by implementing your workaround, but it'll catch up to you at some point. Nimur (talk) 06:07, 24 April 2012 (UTC)

To use your paintbrush example, different paint thinners work better, depending on if you use latex paint, oil paint, or watercolors. And water is the best choice for cleaning the brushes, if you happen to be using watercolor. So, even there, your one-size-fits all approach doesn't work.

Also consider that I learn better by doing than by reading. This is true of many people, perhaps most. I could read about something a dozen times and not understand it, or do it once, learn it, and remember it forever. StuRat (talk) 06:13, 24 April 2012 (UTC)

"X" Power button light of Xaser VI

Hello there, yesterday I cleaned up my pc and disconnected two optional fan inside the case that has been damaged for a long time. After that I turned on pc by pressing power button "X" and noticed that "X" power button light does not blink though my system is running smoothly. The HDD light blinks. I reopened the case and made sure the peripherals are connected properly. But the button still does not blink. How can I address the problem? Am I missing something? thanks--180.234.236.182 (talk) 09:56, 23 April 2012 (UTC)

Power buttons don't normally blink, they are steady on when the device is on. Is this how it behaves now ? If so, this is what it should be doing, and the damaged fans were likely causing voltage drops making it blink. If the light isn't on at all, then something else is wrong. Perhaps you accidentally disconnected the power cord to it. Or, perhaps it just burned out, coincidentally, at this time. StuRat (talk) 14:08, 23 April 2012 (UTC)

• You are right. The light is not On when I press on it and even it stays in same situation when pc is turned on . I checked the disconnected power cord but couldn't locate it. Does it look like two pin cord? I read the manual of thermaltake Xaser VI where case LED connections are mentioned: Power Led, Power SW, H.D.D Led and Reset SW. I found all of them except Power led cord (two pin). Is the power Led cable responsible for this? I overlooked it but couldn't find that cable. Is it really burned out? Can you please tell me which cable is responsible for power button light. Thanks--180.234.238.230 (talk) 17:33, 23 April 2012 (UTC)

• I'd expect it to be a two-pin power cable, yes, but I'm not certain. Is it possible you removed it, thinking it went with one of the fans ? If not, it should still be inside the computer. If you can't find it near the on/off light, look for where the other end should plug into the power supply unit (which is where the cord from the wall outlet plugs go into the computer). StuRat (talk) 18:31, 23 April 2012 (UTC)

• One more thing is that I disconnected my hard drive and reconnected it. Does the light of power button have to do anything with connecting and disconnecting with harddrive?--180.234.238.230 (talk) 19:17, 23 April 2012 (UTC)

• OK, I bet what happened is that your PC lacks an ON/OFF light, and the hard drive has a light that is on whenever it is powered (which was whenever the PC was on). By disconnecting the hard drive, you also lost that light, which was your only visual indication that the PC is on. When you reconnected it, you probably didn't get the plug all the way in, so it doesn't have power to the light. Try pulling the plug all the way out, and completely reseating it. Also check that you didn't bend any of the pins. If so, try to bend them back. StuRat (talk) 19:23, 23 April 2012 (UTC)

• I have just rechecked inside the case and finally, yes, I found that four-pin power cable. Actually that cable was associated with damaged case fan and was connected to PSU power cord. While disconnecting the fan I mistakenly disconnected it from PSU power cord. Now the light is back again. Thank StuRat for helping me out.--180.234.198.76 (talk) 20:20, 23 April 2012 (UTC)

• You're welcome. StuRat (talk) 20:26, 23 April 2012 (UTC)

Resolved

Wouldn't it be nice if...

a blogging programme checked some bit of metadata on an image to see how big it is, before making me wait several minutes while it tries to upload it, only to realise the image is too large?

Wouldn't that seem like an easy/obvious feature to add to, say, Blogger?

Adambrowne666 (talk) 10:02, 23 April 2012 (UTC)

The HTML support for file upload just lets the user choose a file, and sends it across. Allowing scripts to interact with the process would threaten to create security holes. Paul (Stansifer) 13:53, 23 April 2012 (UTC)

Of course, you could always check yourself how big the file is - after all it is being uploaded from the computer you are currently using isn't it? Astronaut (talk) 16:06, 23 April 2012 (UTC)

Both good points, but you neglect to factor in the datum that I'm very lazy, too shiftless to care even about security issues.Adambrowne666 (talk) 23:51, 23 April 2012 (UTC)

It's not so much security for your blog, but browser security in general. If your browser started giving information about arbitrary files on your system to anyone who could get you to click on a link that will pop up the file dialog, you'd start shifting plenty (is that how the metaphor works? I'm not sure.) Paul (Stansifer) 20:32, 25 April 2012 (UTC)

LaTeX figure numbers

I am trying to number figures in a certain way and am having difficulties. What I want to achieve is the following.

1. Number as (chapter #).(section #) if the figure is not within a subsection (meaning that the subsection counter is set to zero), and (chapter #).(section #).(subsection #) otherwise.
2. Follow this with -# if the subsection has more than one figure, and nothing otherwise.

I have achieved the first bit with

\newcommand{\figureplacenumber}{ \ifnumequal{\value{subsection}}{0}{\arabic{chapter}.\arabic{section}}{\arabic{chapter}.\arabic{section}.\arabic{subsection}} }

\renewcommand*{\thefigure}{\figureplacenumber-\arabic{figure}}

However, this leaves a space between the (sub)section number and the hyphen, and this space does not disappear with

\newcommand{\figureplacenumber}{ \ifnumequal{\value{subsection}}{0}{\arabic{chapter}.\arabic{section}\xspace}{\arabic{chapter}.\arabic{section}.\arabic{subsection}\xspace} }

or

\renewcommand*{\thefigure}{\figureplacenumber{}-\arabic{figure}}

and I haven't a clue how to achieve the second part. What should I do? Thanks.--Leon (talk) 10:43, 23 April 2012 (UTC)

Private email communication

How can I communicate privately through email? I don't want commercial providers snooping through my emails to offer me stuff. XPPaul (talk) 12:37, 23 April 2012 (UTC)

I note that Gmail is now reading the contents of my emails and advertising based on it, which rather sucks. I assume this is what you mean. Some type of encoding could work, but the recipient would need to be able to decode it. StuRat (talk) 14:04, 23 April 2012 (UTC)

Does Google do this when we get the mail, or when we read it in a browser? (I almost always read my G mail in Thunderbird.) —Tamfang (talk) 08:47, 24 April 2012 (UTC)

I'm using Firefox. I think it may also happen when I write an email. StuRat (talk) 15:04, 24 April 2012 (UTC)

Encryption. --Mr.98 (talk) 14:05, 23 April 2012 (UTC)

You use an email provider that snoops through your mail in oder to advertise stuff to you????? That has never happened to me in 20 years of using email, not even webmail providers like Hotmail or Yahoo. I suggest you change your provider immediately. I expect it would be easy to find a provider who won't do this. On the other hand, many email providers have a clause in their terms to allow them to release your emails to the relevant authorities under a legal request (for prevention of terrorism and so on) and have a means to store your mail for that reason. Astronaut (talk) 16:04, 23 April 2012 (UTC)

You realize that any email providor has "a means to store your mail" right? That's sort of how they provide an email service to you. Also, yahoo does this as well, can't find anything specific on hotmail but I'd be surprised if they don't. Chris M. (talk) 13:37, 26 April 2012 (UTC)

If you securely encrypt your mail (really securely), your email recipients will need to securely decrypt it. This requires technical knowledge (not much, but just enough that many people will not bother to do it). To the uninitiated, a secure email using, e.g., S/MIME, appears to be an almost-blank ordinary email with a strange binary attachment.

The sad reality is, if you wish to communicate securely, you must seriously limit who you communicate with. Nimur (talk) 17:29, 23 April 2012 (UTC)

As Mr.98 suggested, encrypting your emails is the only way to stop email snooping (through something like PGP). It's not particularly difficult to do, but as Nimur suggested, it severely limits who you can talk to. The other comment I wanted to make was that pretty much all email providers will read your mail contents, not just GMail. As this is how they filter spam. - Akamad (talk) 22:47, 23 April 2012 (UTC)

Webcam formats?

I wonder in what format typical webcams transmit video to the computer. Is it some standard format that the OS knows, or is it some camera-specific raw format that the driver converts in real-time to a standard format? In the latter case, what format does the driver present to the OS? AxelBoldt (talk) 18:18, 23 April 2012 (UTC)

Frequently JPEG, AIUI. ¦ Reisio (talk) 18:24, 23 April 2012 (UTC)

The standard for USB video is called USB video device class, and as Reisio points out, often involves JPEG-compressed frames. Your webcam can do anything it likes if it uses a non-standard device driver.

For example, Video4Linux 2 defines several types of uncompressed and compressed formats. It is the responsibility of the device-driver and kernel-driver to negotiate the format so that meaningful video data streams from source to destination.

The source-code for Video 4 Linux, including the USB driver, is distributed as part of the kernel, available at http://kernel.org and documented in linux-(release)/Documentation/video4linux/uvcvideo.txt - you can download it for free and read all the technical information you need, with no details left out. Nimur (talk) 19:03, 23 April 2012 (UTC)

Some Computing questions

1)Using VoIP, the person who receives the call, gets a random and weird number on his caller ID.Such way, if a person threatens a person over phone via the VoIP, Can the law enforcement trace the location of the phone using the weird number?

2)While the torrent sharing website provide illegal software and other stuffs, Why the government is not taking any action against them?

3)Is there any Xbox 360 emulator available for Windows?Max Viwe | Wanna chat with me? 19:50, 23 April 2012 (UTC)

(1) I don't know. Perhaps your VoiP provider can answer this for you. (2) Copyright is often enforced in civil court via lawsuit by private parties. For example, see the article on the Pirate Bay trial and also the RIAA. (3) This page claims to have an XBox 360 emulator: [1]. RudolfRed (talk) 20:33, 23 April 2012 (UTC)

The Xbox 360 emulator is probably a scam. The "newest updates" bullet points are copied from pcsx2 checkin comments ([2]). See also WP:Reference desk/Archives/Computing/2012 January 19#Xbox 360 emulator.

It has been difficult to take legal action against torrent sites because nothing that they host (torrent files, torrent descriptions, torrent tracking data) actually infringes on copyright. The copyrighted data is sent directly from peer to peer, and the web site is not a peer. -- BenRG (talk) 23:49, 23 April 2012 (UTC)

According to this, the weird number appears if the caller hasn't set their number for caller ID. You can report abusive callers to Skype[3] or many other VoIP services, who should be able to identify them. Or if you're called on a phone, your phone company should be able to handle it (or failing that, contact the police or a lawyer). People have been caught in the past when Skype calls were traced[4]. --Colapeninsula (talk) 08:59, 25 April 2012 (UTC)

Firefox Addons that can make browsing quick by using alphabet

Hi there, A few days ago I installed an addon which make browser easier by using alphabet. User can press ctrl+spacebar or ctrl+shift to bring a small interface which can show the name of the website along with an alphabet (e.g. facebook f) that can directly lead user to that particular website in a new tab if user presses the alphabet associated with the website. For example: http://www.facebook.com = f, http://www.wikipedia.com = w, http://www.youtube.com= y. User can add any website by go to the option of that interface and add web address with certain alphabet that is convenient for user. Can anyone help me to find that addons. Thanks in advance--180.234.198.76 (talk) 20:36, 23 April 2012 (UTC)

You can do the same with Firefox's bookmarks. Open up the Bookmark Manager and to the New Bookmark prompt. Add the Name and Location of your choosing, then put the letter of the alphabet you want in the "Keyword" section. Hit Add to make your bookmark. Now you can use the alphabet as you wanted. -- Tohler (talk) 21:06, 23 April 2012 (UTC)

Vimperator? There are (as usual) one or two alternatives, too, IIRC. ¦ Reisio (talk) 22:18, 23 April 2012 (UTC)

• Apparently it's not that one I am looking for!--180.234.198.76 (talk) 22:38, 23 April 2012 (UTC)

You're right, it's one of the ones listed in Vimperator's external links section. ¦ Reisio (talk) 01:15, 24 April 2012 (UTC)

April 24

Javascript unlimited multiplier.

What's the best possible way to make a multiplication in javascript without getting exponential number or "Infinity". 190.158.212.204 (talk) 02:15, 24 April 2012 (UTC)

I don't know about Java specifically, but, in general, the only way to support an unlimited length number, whether integer or real, without going to exponents and/or hitting a precision limit, is to store it as a character string and do all the calculations manually. This is quite painful. StuRat (talk) 03:10, 24 April 2012 (UTC)

Is this okay?

Extended content

function fullADD(first, second) { /*This is a full adder. It is different from javascript add because this can add big numbers without getting exponenential results, or 'Infinity' when there are big numbers, you have to pass the 2 numbers as a string. I'm not really good at math, or javascript so this is probably a really bad way to do it.*/ cal = new Object cal.FirstString = first.toString() SecondString = second.toString() cal.Firstt = []; for (ANumber = 0; ANumber < cal.FirstString.length; ANumber++) { b = cal.FirstString.substring(cal.FirstString.length - 1 - ANumber, cal.FirstString.length - ANumber); cal.Firstt[ANumber] = b }; cal.Secondd = []; for (ANumber = 0; ANumber < SecondString.length; ANumber++) { b = SecondString.substring(SecondString.length - 1 - ANumber, SecondString.length - ANumber); cal.Secondd[ANumber] = b }; cal.Secondd if (cal.Secondd.length <= cal.Firstt.length) { Firs1 = cal.Firstt; Secon2 = cal.Secondd } else { Secon2 = cal.Firstt; Firs1 = cal.Secondd } IsSecondNumberDefined = true; Offset = false; ArrayResult = [] for (Num = 0; Num <= Firs1.length; Num++) { if (typeof Firs1[Num] == "undefined") { off = (Offset) ? 1 : 0; if (off == 0) { break } else { ArrayResult[Num] = 1; break; } }; if (typeof Secon2[Num] == "undefined") { off = (Offset) ? 1 : 0; Pri = Firs1[Num] * 1 + off; IsSecondNumberDefined = false }; if (IsSecondNumberDefined) { if (Offset) { Pri = (Firs1[Num] * 1) + (Secon2[Num] * 1) + 1 } else { Pri = (Firs1[Num] * 1) + (Secon2[Num] * 1) }; } IsSecondNumberDefined = true Pri2 = Pri.toString(); if (Pri2 >= 10) { Pri2 = (Pri2 * 1 - 10).toString(); Offset = true } else { Offset = false } ArrayResult[Num] = Pri2 } if (ArrayResult.length > 1) { TheResult = (ArrayResult.reverse() + "").replace(/,/g, "") } else { TheResult = ArrayResult.toString() }; return TheResult } function decADD(FirstDec, SecondDec) { /* This thing just enables decimal addition like 3.2+5.4 It counts the numbers after the "." removes the dots adds them and then adds the "." to the final result*/ NumbersAfterTheDot1 = (FirstDec.length - 1) - (FirstDec.indexOf(".")); NumbersAfterTheDot2 = (SecondDec.length - 1) - (SecondDec.indexOf(".")); if (NumbersAfterTheDot1 < NumbersAfterTheDot2) { CUT = NumbersAfterTheDot2; DifferenceOfNumbersAfterTheDot = NumbersAfterTheDot2 - NumbersAfterTheDot1; AddingZeroes = FirstDec.replace(/\./, ""); for (k = 0; k < DifferenceOfNumbersAfterTheDot; k++) { AddingZeroes += "0"; NumberWithoutDots = SecondDec.replace(/\./, "") } } else if (NumbersAfterTheDot2 == NumbersAfterTheDot1) { CUT = NumbersAfterTheDot2; DifferenceOfNumbersAfterTheDot = NumbersAfterTheDot1; AddingZeroes = FirstDec.replace(/\./, ""); NumberWithoutDots = SecondDec.replace(/\./, "") } else { CUT = NumbersAfterTheDot1; DifferenceOfNumbersAfterTheDot = NumbersAfterTheDot1 - NumbersAfterTheDot2; AddingZeroes = SecondDec.replace(/\./, ""); for (k = 0; k < DifferenceOfNumbersAfterTheDot; k++) { AddingZeroes += "0"; NumberWithoutDots = FirstDec.replace(/\./, "") } }; ThaNum = fullADD(NumberWithoutDots, AddingZeroes); fir = ThaNum.slice(0, ThaNum.length - CUT); sec = ThaNum.slice(ThaNum.length - CUT); return fir + "." + sec } function add(fir, sec) { /*Global adding function*/ if (typeof fir == "number") { fir = fir.toString() } if (typeof sec == "number") { sec = sec.toString() } if (/[^0-9\.,]/.test(fir) || /[^0-9,\.]/.test(sec)) { return "ERROR: Please use numbers as a string" } if (/[\.,]/.test(fir) || /[\.,]/.test(sec)) { if (/\./.test(fir)) { if (fir.match(/[\.,]/g).length > 1) { return "Error, you can't add comas or dots more than once. (comas and dots trigger the decimal calculator)" } } if (/\./.test(sec)) { if (sec.match(/[\.,]/g).length > 1) { return "Error, you can't add comas or dots more than once. (comas and dots trigger the decimal calculator)" } }; if (!(/\./.test(fir))) { fir = fir + ".0" }; if (!(/\./.test(sec))) { sec = sec + ".0" } return decADD(fir, sec).replace(/0+$/g, "") } return fullADD(fir, sec) } function fullMUL(FirstNumber, SecondNumber) { Multplic = new Object Multplic.d = FirstNumber Multplic.c = SecondNumber Multplic.tumbt = []; for (aNu = 0; aNu < Multplic.d.length; aNu++) { SpmeNumber = Multplic.d.substring(Multplic.d.length - 1 - aNu, Multplic.d.length - aNu); Multplic.tumbt[aNu] = SpmeNumber }; Multplic.tr = []; for (aNu = 0; aNu < Multplic.c.length; aNu++) { SpmeNumber = Multplic.c.substring(Multplic.c.length - 1 - aNu, Multplic.c.length - aNu); Multplic.tr[aNu] = SpmeNumber }; Multplic.tr if (Multplic.tr.length <= Multplic.tumbt.length) { Fi1 = Multplic.tumbt; Se2 = Multplic.tr } else { Se2 = Multplic.tumbt; Fi1 = Multplic.tr } MultiplicArray = []; O = 0; ArrayOfTheFirstLoop = []; /*Here there are 2 for loops, it is for multiplicating arrays.. For example 56*87, (first loop) it takes the "6" (second loop) Multiplies for 7 and 8, then it takes the(first loop) "5" and multiplies (second loop) for 7 and 8 then reverses. adds zeros And adds them O is Offset liO and Shup are random variables. Each of one means the number of the string Example: 5642x46 Shup= 3 and liO = 1, would mean 4*5 (Remember arrays start from Zero) (If you still don't understand please see below) (second number) Se2=["6","4"] Fi1= ["2","4","6","5"] Se2[0]*Fi1[0]=12 Instead of Zeros we use liO and Shup, in this case liO would range from 0 to 4 on 4 checks if it is undefined and see if there is an offset) Shup would range from 0 to 1. For each Shup liO loops from 0 to 4. Se2[Shup]*Fi1[liO] And thats what those for loops do. (sorry about silly names, Normally I use short names to type them faster.) */ for (Shup = 0; Shup < Se2.length; Shup++) { for (liO = 0; liO <= Fi1.length; liO++) { if (typeof Fi1[liO] == "undefined") { ArrayOfTheFirstLoop[liO] = O + ""; MultiplicArray[Shup] = ArrayOfTheFirstLoop.reverse().toString().replace(/,/g, ""); break } Tiy = (Se2[Shup] * Fi1[liO] + O * 1).toString(); if (Tiy.length > 1) { yesn = Tiy.substring(1); O = Tiy.substring(0, 1) } else { O = 0; yesn = Tiy }; ArrayOfTheFirstLoop[liO] = yesn } O = 0 } ArrayWithAddedZeros = []; for (Some = 0; Some < MultiplicArray.length; Some++) { EachNumberWithZeroes = MultiplicArray[Some]; for (k = 0; k < Some; k++) { EachNumberWithZeroes += "0"; } ArrayWithAddedZeros[Some] = EachNumberWithZeroes } Result = ""; for (AddingArray in ArrayWithAddedZeros) { Result = add(Result, ArrayWithAddedZeros[AddingArray]) }; return Result = Result.replace(/^0+/, "") }

65.49.68.172 (talk) 05:09, 24 April 2012 (UTC)

If you really do want arbitrary precision math, you might consider JavaScript BigNumber. However, it seems lately on the computing desk, we're rolling our own reinvented wheels (replete with naïve mistakes that have been resolved by our very smart forebears who authored the standard solutions); so by all means, use your implementation! After a quick glance, I decided that its variable names are too silly for me to follow, but I assume that you'll be able to quickly discover any incorrect implementation details. Nimur (talk) 05:53, 24 April 2012 (UTC)

Replaced some silly vairables with non-silly variables. 190.60.93.218 (talk) 14:12, 24 April 2012 (UTC)

comparison between android and ios development

I've just spent more than a day trying to get "hello world" up and running on Android emulator with Eclipse, without success. I've read that iOS is much easier to get started with. Can anyone confirm that it is easy enough, and whether there are any major pitfalls? I'm about going mad with Android, and ready to quit, but I don't have a Mac yet, so I might as well give Android an extra go. I just want to know there's a light at the end of the tunnel, should I decide to quit Android forever. IBE (talk) 05:36, 24 April 2012 (UTC)

There're over seven-hundred people in irc://irc.freenode.net/android-dev*, and over two-hundred in irc://irc.freenode.net/iphonedev you could speak with in real-time. As the numbers may indicate to you, Android is less expensive and (likely not coincidentally) more popular; I dare say the difficulty in developing for either is largely comparable, however. ¦ Reisio (talk) 19:18, 24 April 2012 (UTC)

There are lots of tutorials for both Android and iOS. In terms of getting started, Android isn't hard, and there's a lot of online support. If you don't like IRC, you can check a web forum[5][6][7] and this page has more resources[8]. --Colapeninsula (talk) 09:10, 25 April 2012 (UTC)

Thanks to you both for the suggestions. "Easy" and "hard" are matters of opinion, and having just spent 3 days getting "hello world" running, I would call Android unreasonably hard. I googled my error message, and the suggested solution was to install something I already had. For others who are interested, I finally solved the problem using something I came across more or less by accident: see here. From there, it was easy enough to fix, but it was very hard to find the right site. I had to configure Eclipse via Eclipse->Window->Preferences->Android, and change the path from C:\Users\<my name>\android-sdks to C:\Program Files\Android\android-sdk. The sdk was installed in both places, and Eclipse got the wrong one. I find this highly counterintuitive, and an annoying hurdle for getting "hello world" up and running. You are free to differ. IBE (talk) 09:33, 25 April 2012 (UTC)

Unnecessary music in a videogame

A well-known game has a room containing nothing special except a room-specific music, so the player is expected just to pass through to the next room, which means s/he's supposed to listen to less than 10 seconds of music, or less. Why did they provide SIX minutes of music instead? Note that it is not played in any other part of the game. --151.75.48.159 (talk) 07:12, 24 April 2012 (UTC)

My guess is that the musician is a friend of one of the developers, who promised he would play the entire song in the game. But, for whatever reason (didn't go with the game, etc.), they decided to marginalize it by playing it in that one room only. StuRat (talk) 07:16, 24 April 2012 (UTC)

Can the OP give an example of a situation where music IS necessary in a video game? Most of it annoys the crap out of me. HiLo48 (talk) 08:10, 24 April 2012 (UTC)

By unnecessary I meant superfluous. --151.75.48.159 (talk) 10:55, 24 April 2012 (UTC)

Or, the music was supposed to be included elsewhere as well, but due to time constraints/changing requirements, it was left out. A lot of games have content included on the disks that isn't actually used at all, even in the DOS era. 173.68.52.122 (talk) 02:32, 30 April 2012 (UTC)

Animated GIF frame order

When using the loop option for an animated GIF with 4 frames, it wants to do them in this order:

1,2,3,4
1,2,3,4
1,2,3,4
  .
  .
  .

However, I'd like to get:

1,2,3,4,3,2,
1,2,3,4,3,2,
1,2,3,4,3,2,
  .
  .
  .

Is there any way to get this order, without duplicating frames 2 and 3 as frames 6 and 5 ? I use ImageMagick to do the stitching. I specify the inputs as "frame*", would it work if I gave it "frame1 frame2 frame3 frame4 frame3 frame2" as the inputs ? If so, would the result be any smaller than if I duplicated the frames as frames 5 and 6 and used "frame*" in the input string ? StuRat (talk) 16:03, 24 April 2012 (UTC)

When you put a * in a command line, you're doing filename globbing. How that really works varies:

• On unix/linux/bsd/osX globbing is done by the shell (e.g. bash), and the called program is passed a command line with all the filenames already expanded. It's my recollection that POSIX insists filenames be in the prevailing collation order (which means they're probably in alphabetical order for you).
• On Windows command.com/cmd.exe the filenames aren't globbed by the shell - the program is passed just a * and has to do whatever globbing it wants itself. Imagemagick does, but I can't see a guarantee of collation order.
• On Windows Powershell I think the globbing is done by the shell; I don't know the ordering.

Assuming collated globbing, if you say frame * you'll get all the frame file names, in sorted order. So just explicitly specifying them is the same as what the globbing generates, but you get to control things and specify an alternate order. -- Finlay McWalterჷTalk 17:14, 24 April 2012 (UTC)

Thanks. I did a bit of testing, and I can get it to do what I want with this ImageMagick command:

convert f1.ppm f2.ppm f3.ppm f4.ppm f3.ppm f2.ppm animation.gif

However, the resulting animation is far larger than if I had done:

convert f1.ppm f2.ppm f3.ppm f4.ppm animation.gif

So, apparently it just duplicates the frames, rather than linking to them in the order I specified. Is there any way around this, or is this beyond the capabilities of an animated GIF ? StuRat (talk) 18:05, 24 April 2012 (UTC)

It is beyond the capabilities as far as I understand it. The format just iterates through frames; it doesn't have a sophisticated frame control system. You can make it specify things like the number of repetitions, and the time between individual frames, but it is going to march from beginning to end no matter what. (And for what it's worth, APNG seems more or less the same in this respect. MNG seems more complicated in its capabilities but I'm having a hard time really seeing what they are; you can do loops within loops but I think they're still just forward moving, so it doesn't change much in this case.) --Mr.98 (talk) 01:08, 26 April 2012 (UTC)

OK, thanks. Too bad, as going back down from the last frame to the first frame gradually usually makes more sense than jumping directly back. StuRat (talk) 03:44, 26 April 2012 (UTC)

Problem with external hard drive

A few weeks ago (about early March) I got a 6TB external hard drive and had problems with it. I asked here. I've returned two of them and got replacements. The HD has USB 2, firewire, and eSATA connections. I want to use it with eSATA. The problem is that using the eSATA connection, I can't get more than 2.19TB of files onto it using the eSATA - it starts getting very slow and then it stops and locks up the computer. I've tried it about 20 times over the weeks. I do not have that problem with USB 2, but naturally USB 2 is too slow. The company thinks that the problem is with my computer and suggested trying it on a different computer. I checked around, and I don't have access to another one with eSATA. But since USB 2 works, I decided to get a USB 3 to eSATA adapter, and use the USB 3 connection on the same computer to the eSATA connection on the HD. The USB3/eSATA method works - no problem.

I noticed that if the HD uses 512-byte sectors/clusters, 2^32 of them is 2.199TB - just about the amount where I have the problem with eSATA. Could there be something about my motherboard that causes that problem (I got it new last year)? Could there be a problem with the company's drivers for the eSATA (I have the latest ones installed)? Bubba73 ^{You talkin' to me?} 18:54, 24 April 2012 (UTC)

The symptoms you describe sound very much like what happens to a program when the memory is filled up and paging space must be used. I suspect that eSATA uses a 32 bit index, and when addresses get larger than that it uses some kludge to try to keep working, but one as bad as paging space, unfortunately. I can see a few options:

1) Reformat the HD to use larger sectors/clusters. You'd want them at least 3 times larger, so we should go with the next multiple of 2, and make it 4 times larger, or 2048-bytes per sector/cluster.

2) Continue to use your current workaround.

3) Return that external hard drive, and use 3 hard drives of 2 TB each, instead. This setup might also last longer. StuRat (talk) 19:21, 24 April 2012 (UTC)

RE: 3) That may well be a good idea for economy and versatility as well. ¦ Reisio (talk) 19:25, 24 April 2012 (UTC)

Sectors and clusters are not the same thing. You can't change the sector size. I don't know what the problem is here, but your suggestion that some kind of "paging" is going on is silly. -- BenRG (talk) 22:09, 24 April 2012 (UTC)

That was not my suggestion. I was using that as an analogy, as indicated by the words "like" and "as", to show that some resource was being used up (similar to memory) and thus some kludge was being used in an attempt to keep going (similar to paging space), but that this was working far more slowly (like paging space). I then proposed that the limiting resource, in this case, is indeed 32-bit indexing. StuRat (talk) 16:05, 25 April 2012 (UTC)

Are you getting the same transfer rate with your USB3 adapter? Less? More? ¦ Reisio (talk) 19:25, 24 April 2012 (UTC)

Some replies: (1) I tried reformatting to 2048-byte clusters once. I still had the same problem but I'm not positive I was successful in reformatting it that way. (2) If I can't use this drive I'm out about $450. (3) The transfer rates with the USB3/eSATA combination are comparable to the eSATA rate. I was reading from a USB 3 drive and writing to the 6TB drive. With eSATA it was up to 120MB/sec but around 100MB/sec most of the time. With USB3/eSATA combination, it was around 100MB/sec (so close enough). (With USB 2 it was 25MB/sec.) Bubba73 ^{You talkin' to me?} 19:51, 24 April 2012 (UTC)

I selected this drive because it has two 3TB drives in RAID. I have it set to RAID0, but my tests don't indicate that it is any faster than my USB3 external HD in sequential reading. I would have been better off to get two 3TB USB3 drives for less than the 6TB eSATA RAID drive or two 4TB USB3 drives for about the same price! Bubba73 ^{You talkin' to me?} 19:56, 24 April 2012 (UTC)

Yes, I think you might be on the bleeding edge, meaning you are paying higher prices to get the latest technology, which is not yet fully supported. Incidentally, why do you need 6 TB ? Do you want to store hundreds of movies on there ? StuRat (talk) 21:10, 24 April 2012 (UTC)

Changing to a larger cluster size doesn't affect the number of sectors. You should use clusters of 4K or larger because many newer drives actually have 4K sectors but pretend to have 512-byte sectors for backward compatibility. If you use 2K clusters you will end up with a lot of half-sector writes, which is slow. -- BenRG (talk) 22:09, 24 April 2012 (UTC)

It is for a database that is currently 2.7TB (and is on a 3TB drive) and will be growing to around 5TB. Right now it is all one big file on the 3TB drive. But I realized that doesn't really have to be in one file or all on one drive. I first tried to copy it as one file to the 6TB drive with Windows copy, but it failed. The second try failed. I thought it might not like files that big, so I decided to break the file into 500GB parts and rewrite the program that uses the data. That failed in the same way. Then I tried breaking it into 50GB parts and analyze what is happening with the transfer speed, which is how I discovered the problem around 2.19TB. Bubba73 ^{You talkin' to me?} 23:33, 24 April 2012 (UTC)

To give you an idea of the speed, with USB2 (and the USB3/eSATA combination), performance varied but it never got terrible. With eSATA, just writing to the disk from memory (i.e not copying from another HD), write speed started at 100 to 120 MB/s. When it got somewhere over 2TB, it slowed to under 4MB/second, and after doing that for a while, it would lock up the computer, requiring a hard reboot. Bubba73 ^{You talkin' to me?} 03:00, 26 April 2012 (UTC)

How bad is the performance with the USB3/eSATA combo ? You might want to use USB3 alone until you fill it to that point, then switch to the combo. StuRat (talk) 14:39, 26 April 2012 (UTC)

The USB2 performance is about 25MB/sec, which is not good enough (5TB would take 55 hours - way to slow). I can't use USB3 alone because the 6TB HD has USB2, eSATA (and Firewire). The USB3/eSATA performance is about the same as the eSATA performance, and it doesn't encounter the problem, so I'm sticking with that. Bubba73 ^{You talkin' to me?} 15:14, 26 April 2012 (UTC)

OK, I guess that's the best you can do with your current configuration. StuRat (talk) 15:22, 26 April 2012 (UTC)

Insight about recovery disk

I am new to the concept of recovery disk of the last Windows versions. The last time I installed Windows, it was from a single CD, which was shipped by Microsoft. So, I am a little bit insecure about the way to deal with it. I need some basic fact-checking and questioning:

1. when I get a new laptop, there would be an image of Windows that has to be installed on a different partition right?
2. I have to make a back-up of this image into a DVD. But how many DVDs I'll need? And why not a pen-drive?
3. this image can only be installed in the computer where it was shipped. But what about if I buy a new HDD, how can I install this Windows image? Or, can I install this Windows image everywhere? — Preceding unsigned comment added by 88.8.68.89 (talk) 20:31, 24 April 2012 (UTC)

I hope you don't mind, I've tweaked your post to use a numbered list, which will answering your questions slightly easier -- Finlay McWalterჷTalk 20:52, 24 April 2012 (UTC)

OK. 20:54, 24 April 2012 (UTC)

1. Yes, that's almost always the case nowadays.
2. Yes. How many varies (you're also backing up all the additional stuff they install, like trialware of anti-virus and office programs)
3. Really you can only reinstall on this machine (and others of the same model from the same manufacturer).

Some companies will sell you a recovery DVD (so you don't have to burn one). -- Finlay McWalterჷTalk 20:56, 24 April 2012 (UTC)

For 2, the number of disks might be between 2 and 5. I've not seen one that offered a pen drive, but they may do that now. In practice these restore disks often use a rather crappy OEM version of Norton Ghost. Personally, for problems like this, I'd instead make an image myself with something like Clonezilla. -- Finlay McWalterჷTalk 20:58, 24 April 2012 (UTC)

As to part of 3 "what about if I buy a new HDD" (and you could also ask "what if my hard disk breaks and I replace it") - I think the first restore disk is an El Torito bootable disk. -- Finlay McWalterჷTalk 21:02, 24 April 2012 (UTC)

Thanks. 88.8.68.89 (talk) 21:09, 24 April 2012 (UTC)

Re the pen drive (depending on software) it's generally do-able - in most cases you just save to the pen drive directory instead of the DVD directory. However you need to have "boot from USB" enabled and possible - this is a bios setting. If this is what you want to do it is actually quite easy and not painful, provided your computer supports this.Oranjblud (talk) 01:09, 27 April 2012 (UTC)

April 25

BIOS INT 10H source of pixel data for characters

When a call to INT 10H comes and the ASCII bits describing, say, the character 'A' are in AL, where exactly in the computer are the bits that describe the pixel formation of the glyph 'A' that INT 10H goes to to get them on the screen? If your answer is that 10H's job ends when it tells the graphics card in language it understands to put 'A' on the screen, my question remains, where exists the pixel data for the most basic of characters before anything so fancy as font files are loaded up? 20.137.18.53 (talk) 12:15, 25 April 2012 (UTC)

In a "real" PC (in times of yore, before layers of emulation abstracted how so many things worked) there was a character ROM which stored 9x14 pixel bitmaps for each character in code page 437. In the original IBM Monochrome Display Adapter this was a discrete ROM device, over which the card would brook no override. Later cards, with more memory, allowed to to copy this ROM in the the card's own RAM (they were all addressable locations in the host PC's address space) and direct the controller to use that instead (allowing you to alter the appearance of characters). I don't off hand know the memory map involved. -- Finlay McWalterჷTalk 13:12, 25 April 2012 (UTC)

Hmm, on further cogitation I don't think that (in early devices) the graphics adapter's ROM or RAM were mapped into the host device's Memory-mapped I/O (because they'd take up too much room). They were later, but I've lost my giant-book-of-graphics-chips of that era, so I don't know the specifics of when. -- Finlay McWalterჷTalk 13:28, 25 April 2012 (UTC)

The actual character array (that we might call the screen) was an area of memory in the display adapter's limited RAM. INT 10H calls (which were often implemented by code in the graphics adapter's own expansion ROM) would read and write character codes into this space. Asynchronous to that, the graphics adapter continually generated a stream of pixels as the raster proceeded along and down the screen. As it did so, it would fetch a byte or two from the character map, and would look up the corresponding bitmap data in the character rom, giving actual pixels for it to emit. -- Finlay McWalterჷTalk 13:17, 25 April 2012 (UTC)

For some diagrams, this page discusses the character generator circuitry for an early Atari computer; the arrangements (for that part) were much the same in an IBM-MDA. -- Finlay McWalterჷTalk 13:36, 25 April 2012 (UTC)

Xcode and link to website and addition of more text

Hi, I'm new to Xcode and can't seem to find out how to add loads of text to the screen, I tried adding it to a label but this seems to have a finite amount of characters it allows to get displayed, I added a scroll bar in the hope that I could view the text which is not displayed, does anyone know how I could add more text to the screen thanks, I am also trying to link to a website with a button but can't seem to do this without leaving the application.84.203.137.50 (talk) 13:43, 25 April 2012 (UTC)

Gmail Account

Here i got a question regarding gmail account , My question is this, can i delete the digits in my gmail username. Like my username is <redacted>55@gmail.com , i want to delete the 55 in my username,is thid possible. Any help will be greatly appreciated. — Preceding unsigned comment added by 78.86.121.138 (talk) 13:52, 25 April 2012 (UTC)

You have to create a new account, if the name usman is still available. — Preceding unsigned comment added by 88.8.68.89 (talk) 14:22, 25 April 2012 (UTC)

And that's a big "if". Likely the reason that number was added was because, without it, that name was already in use. StuRat (talk) 19:02, 25 April 2012 (UTC)

From Google's help pages: "it's not currently possible to change your Gmail username after you've registered. You can, however, create another Google Account with a different Gmail username." - Cucumber Mike (talk) 14:24, 25 April 2012 (UTC)

If you do create a new account, it's possible to automatically forward any emails you get from one to the other. So you don't have to check both accounts. And you can change the "from" address of your mail so it reads which ever one you prefer. - Akamad (talk) 23:05, 25 April 2012 (UTC)

That is possible. I had to do this once as my address was listed once as "dismis" instead of "dismas". So I set up a new account under the first spelling to forward all mail to the second. Dismas|^(talk) 01:13, 29 April 2012 (UTC)

Running process and automatic sleep

If Windows 7 is running a process (like doing a backup) and it's set to get to sleep in a time shorter than that needed to the backup, what would happen? Go to sleep anyway? — Preceding unsigned comment added by 88.8.68.89 (talk) 14:05, 25 April 2012 (UTC)

Windows provides many ways to let a process know that the system is changing: for example, WM_CLOSE tells a desktop-application style program that it "should please stop running." Other messages exist, including special cases for system hibernation and sleep events. An application programmer may choose to handle these messages, or ignore them. The operating system may decide to wait pleasantly for a response, or it may shut down anyway, depending on the type of shutdown (and the permissions of the person or program who initiated it). For example, read this Microsoft tech note on writing good power-aware applications, which links to an explanation of, e.g., the PBT_APMSUSPEND event, a special message sent to the application "about two seconds" before the machine goes to sleep. (If your application's designer couldn't write the code to save your work - or at least to put it in a consistent, recoverable/resumable state - in under two seconds, you need a better application).

On POSIX-compliant computers, we have two ways to interrupt a process and tell it that it needs to stop running. Loosely speaking, these are SIGTERM, which tells the process "Please terminate, you have a few moments to wrap up." We also have SIGKILL, which doesn't tell the process very much at all: the kernel will kill the process for you.

Ultimately, remember that the operating system's job is to politely mediate requests between many different programs (and potentially, many users); and to politely balance hardware realities (like turning the power off) against software requests (like a program that needs more time to save your work to disk). Good software-engineers use all the information that the system provides so that the program does the right thing without confusing the user. Nimur (talk) 16:44, 25 April 2012 (UTC)

WM_CLOSE means that the user clicked the X in the upper right corner of the window or did something equivalent like pressing Alt+F4. The application is free to respond however it wants, just as with any other button click or key press. WM_CLOSE is sometimes sent in other ways—for example, when you try to terminate an application in Task Manager, I think it sends WM_CLOSE first and waits a few seconds before resorting to more drastic measures. I don't think this is relevant to the original question, though, which was about whether a backup application can/will prevent the computer from sleeping.

Programs can call SetThreadExecutionState to prevent the system from sleeping. Many don't, though. I don't know of any way to tell except by doing the obvious experiment. -- BenRG (talk) 22:32, 25 April 2012 (UTC)

April 26

Double OS and double hibernate?

If you have two OSs in one computer, can you put both to hibernate and choose which want you to wake? That would be a kind of GRUB loader. 14:50, 26 April 2012 (UTC) — Preceding unsigned comment added by 88.8.68.89 (talk)

In principle, yes - but it depends on the order of your bootloaders. For example, the Windows bootloader won't give you a choice if you hibernated (presumably to reduce the possibility of making changes 'behind its back' with potentially deletrious consequences on resume) - I've not paid enough attention to notice if any Linux distributions do the same with GRUB. 131.111.255.9 (talk) 16:11, 26 April 2012 (UTC)

Classful networking and CIDR

I more or less know what classful networking and CIDR are. And I know CIDR came after classful and makes use of a subnet mask. So my questions: did subnet masks exist before CIDR or were they introduced for CIDR? If they were introduced for CIDR does this mean the IP protocol had to be changed? If they already existed what were they used for and, again, were any changes needed to be made to the IP protocol?

Thanks and sorry for all the question. Im really just starting networking and I cant help getting caught up in all the details even though I may not need them right now. --TuringMachine17 (talk) 22:47, 26 April 2012 (UTC)

We have articles on both CIDR and Subnet masks. From what I can tell from the article, they came about at the same time. RudolfRed (talk) 00:41, 27 April 2012 (UTC)

I saw this yesterday, and was about to answer they were different, but from what our articles suggest, they seem to have come about together. When I hear CIDR I think the notation (/16) but obviously it's broader.

But there's a caveat. While the internet edge routers wouldn't use subnetting like we think about it today, the RFC introducing CIDR talks about subnetting. What's special about CIDR is variable-length subnetting. Whether that difference is meaningful depends on whether or not those early networking devices/stacks respected other subnets before CIDR was contemplated. That I do not know. But the term "subnet" was used to describe the fixed subnets of classes. A class A range could be expressed as a subnet, and that terminology was used back in 1993. Shadowjams (talk) 16:10, 27 April 2012 (UTC)

April 27

MS-Excel

What is MS-Excel? — Preceding unsigned comment added by Aadya mishra (talk • contribs) 05:14, 27 April 2012 (UTC)

It means Microsoft Excel. Bubba73 ^{You talkin' to me?} 05:37, 27 April 2012 (UTC)

iPhone Camcorder/iMovie

Why cannot i import camcorder films from my iPhone into iMovie please?--85.211.154.241 (talk) 05:56, 27 April 2012 (UTC)

Do any of these links help?[9][10][11] If not, it would be useful if you told us the particular problem you are having and the version of iMovie and other software you are using. --Colapeninsula (talk) 09:04, 27 April 2012 (UTC)

iPhone3 and iMovie 11.--85.211.154.241 (talk) 15:12, 27 April 2012 (UTC)

Sorry, forgot to thank you for the links, I think that the first one will be helpful. — Preceding unsigned comment added by 85.211.154.241 (talk) 15:18, 27 April 2012 (UTC)

Leading spaces are stripped out of Access table

I am using Access 2007 and importing data from a .csv file into text fields in a table. Some of the text fields have leading spaces which are needed and I want to keep them but Access strips them all out when the data is imported. How can I stop this happening please? Gurumaister (talk) 07:39, 27 April 2012 (UTC)

Can you put quotation marks around the individual data items, including the leading spaces? Comma-separated values suggests this. --Colapeninsula (talk) 09:10, 27 April 2012 (UTC)

Unfortunately, I can't. The .csv is an export of a name and address file from another (non-Access) database so the data comes out without quotation marks. Surely having leading spaces stripped out should be a matter of choice and therefore optional? I am finding it very frustrating. Gurumaister (talk) 13:22, 27 April 2012 (UTC)

Access handles all unquoted spaces before data as just ignorable whitespace and ignores it. I don't see any way around that with Access's interface. Your options, as I see them, are 1. Have the other database spit out the data in a quoted fashion, or 2. Put together some kind of CSV pre-processor that adds the quotes in for you automatically. (The latter is only a moderately difficult scripting task, as far as scripting tasks go.) --Mr.98 (talk) 14:27, 27 April 2012 (UTC)

This Python script does that (blindly - even elements without whitespace get quoted anyway). It reads stdin and write stdout. -- Finlay McWalterჷTalk 14:55, 27 April 2012 (UTC)

#!/usr/bin/python
import csv,sys
for r in csv.reader(sys.stdin):
    for i in range(0,len(r)):
        r[i] = '"%s"'%r[i]
    print ','.join(r)

Can you get an intermediate file between database 1 and 2 (this is in line with what 98 talks about as a pre-processor)? Shadowjams (talk) 16:02, 27 April 2012 (UTC)

Can you predict which fields should have leading white-space? If so you can write an update query in Access that re-adds the whitespaces back in as part of either the import routine or a separate query post import of data. ny156uk (talk) 13:52, 28 April 2012 (UTC)

Presumably the amount of whitespace varies in an unpredictable way, otherwise it would be a simple workaround to just tack on some whitespace. --Mr.98 (talk) 14:41, 28 April 2012 (UTC)

Python exception fail

Resolved

Why isn't this exception caught?

try:
    j = "rgb".index(instring.pop(0))
    ...
except ValueError,IndexError:
    ...

Traceback (most recent call last):
 File "mug1.py", line 36, in <module>
   j = "rgb".index(instring.pop(0))
IndexError: pop from empty list

I tried unpacking the expression:

    ch = instring.pop(0)
    j = "rgb".index(ch)

but that didn't help. —Tamfang (talk) 19:37, 27 April 2012 (UTC)

You need parens around ValueError,IndexError to make it a tuple. As it is you're catching ValueError into an object called IndexError. --Sean 19:48, 27 April 2012 (UTC)

I see. That's a feature I haven't used much. Thanks! —Tamfang (talk) 00:06, 28 April 2012 (UTC)

April 28

What do we call this character?

The character in question appears between the words in the blockquote:

words‎words‎words

What do we call it? I thought it was a zero-width space, but when I copy/pasted it into a URL (http://en.wikipedia.org/wiki/‎) I was given the invalid title page, so apparently it's an invalid character. Nyttend (talk) 14:09, 28 April 2012 (UTC)

If your and my respective cuts and pastes preserved it okay, it's unicode U+200E, the left-to-right mark -- Finlay McWalterჷTalk 14:15, 28 April 2012 (UTC)

How odd — I encountered it while copy/pasting a few subcategory names into Notepad from Commons:Category:Streets in Bloomington, Indiana. If you copy the name of a street and the number of files in the category (everything from the left bracket before the plus or multiplication sign until the parenthesis after the number of files) and go character by character through the result, you'll find one of these characters immediately following at least some of the category names; I tested it with Adams and Grant Sts, and I expect that there are more. Nyttend (talk) 14:23, 28 April 2012 (UTC)

It's in the original HTML sent by the server - I imagine Mediawiki puts it there for cases where a category name contains R->L characters, and they want to make sure the (1 C, 25 F) thing gets laid out consistently. -- Finlay McWalterჷTalk 15:01, 28 April 2012 (UTC)

Stickers on laptop: remove or not?

And why do they put stickers on laptops at all? XPPaul (talk) 22:38, 28 April 2012 (UTC)

Assuming you mean stickers that tell you about the manufacturer, specs, etc., they do that as advertising, mainly. As for removing them, that's a personal preference, but beware that they may not remove easily, leaving behind an ugly sticky spot. Anything which removes the slime may also damage a plastic case. StuRat (talk) 22:48, 28 April 2012 (UTC)

Advertising what for? If you have already bought the laptop... If it's for others to see, they could have put them on a more visible spot... XPPaul (talk) 22:53, 28 April 2012 (UTC)

Well, there's a limit to what consumers will tolerate, and making your laptop look like an Indy car would put it over that limit. (Although Apple manages to put their logo in a highly visible location, but not in sticker form.) StuRat (talk) 23:05, 28 April 2012 (UTC)

What stickers? Mine has four. There are two on the front, pretty ones from Intel and Microsoft, telling me what processor and what version of Windows I have. They are pure marketing and could be removed. (But see Stu's warning above re sticky mess.) One on the back contains the serial number (often abbreviated to S/N or similar). This is critical if you ever want warranty service from the manufacturer or its representative, so don't remove that. The other has the national contact phone number of the supplier, for when I want service. Think I'll leave that too. HiLo48 (talk) 22:55, 28 April 2012 (UTC)

Right, I meant the stickers on the palm-rest. Those on the back are useful and non-obstrusive. XPPaul (talk) 22:58, 28 April 2012 (UTC)

Well you can remove those, too, and if your laptop is ever stolen it might well put the thief at a disadvantage — what you don't want to do is lose the information... if you want it. :p
Most of them come off alright, and if you didn't know one of the best ways to remove excess adhesive left by a sticker is with the sticker you just removed. The last Windows sticker (IIRC) I removed, though, had an awful gel adhesive that was truly a pain to remove... but it did come off eventually. ¦ Reisio (talk) 23:00, 28 April 2012 (UTC)

I don't see the disadvantage for a thief if he doesn't know the s/n of a laptop. Quite in contrary: if the thief let's the s/n there, there's a low chance of recovering the laptop. XPPaul (talk) 23:18, 28 April 2012 (UTC)

Mac screen not framed in window

I think I must have inadvertently changed my screen viewing options but for the life of me I can't figure out how to get back to regular viewing (I've searched in system preferences everywhere). The problem is this: Until today the dock t the bottom of my imac screen, and the menu bar at the top were always visible. Now, they disappear and only appear when I move my mouse pointer to those areas. Meanwhile, it appears that the entire screen size has magnified, such that icons that were near the top or bottom of the screen and near the edges are now partially or wholly off the screen, and when I move my mouse pointer up the entire screen shifts within the frame. Any help?--108.54.17.230 (talk) 23:15, 28 April 2012 (UTC)

I don't know about Macs, specifically, but that behavior sounds like what happens when you (or some application you used) set the screen resolution beyond what your monitor or graphics card supports. Try lowering the screen resolution. StuRat (talk) 23:22, 28 April 2012 (UTC)

I also don't know about Macs, specifically, but I'll answer anyway too. That behavior looks like a universal access feature for seeing impaired, a 'zoom' feature. To turn it off, under System Preferences, go to Universal Access and look for zoom. This feature zooms in on a portion of your screen at greatly increased magnification with a keyboard shortcut. Some people love this, but I find it slightly disorienting.XPPaul (talk) 23:35, 28 April 2012 (UTC)

Thanks for the answers. Neither is the issue though. In universal access, zoom is set to off. When I lowered the screen resolution, everything became huge, and the icons on my screen, where the usually are, were now all overlapping, so it can't be that either.--108.54.17.230 (talk) 23:57, 28 April 2012 (UTC)

Sound like you raised the resolution. Go the other way. StuRat (talk) 23:58, 28 April 2012 (UTC)

No, when you lower the screen resolution everything gets bigger. Try it. I went from 2560 x 1,440 to 1920 x 1200 in the test. By the way, learning from the menus displayed, I checked what the "native screen resolution" for my 27" imac is, using a google search, and the current resolution is the "native".--108.54.17.230 (talk) 00:08, 29 April 2012 (UTC)

I've also seen this happen when swapping monitors or graphics cards, if the resolution was set to a value the first monitor or graphic card supports, but beyond what the new monitor or card supports. (The graphics card issue could happen without your knowledge, if the premium graphics card goes bad/get's jostled loose and you computer automatically reverts to it's default on-board graphics.) StuRat (talk) 00:02, 29 April 2012 (UTC)

That might be it. I can tell you this occurred suddenly today, working normally this morning. But it's alwats possible I hit some weird combination of commands while typing earlier. It seems more like a "full screen mode", like your browser does where all the menu bars are hidden and only become visible when you page over them.--108.54.17.230 (talk) 00:08, 29 April 2012 (UTC)

Windows' license of a wrecked computer

If I buy a computer with Windows on it, but somehow manage to break it completely, like falling from a cliff (anyway, the computer is not well and running somewhere). Can I install the Windows that I bought a license from into a new computer? Imagine that I buy a the same model again, but without Windows. XPPaul (talk) 00:26, 29 April 2012 (UTC)