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March 17

Calculating Powers of 2 in Octave

  I'm new to Octave, and I'm trying to calculate powers of two from 1 to 50. I tried using the following code

n=1:50; m=2^n; disp(m)

but I keep getting the error message error: for x^A, A must be square. What am I doing incorrectly, and how do I fix it? Thanks. Rocketshiporion♫ 01:43, 17 March 2011 (UTC)

Well, since exponentiation doesn't require A to be square ^ must mean something different. However, the manual tells ^ means exponentiation, so no clue from there. 212.68.15.66 (talk) 06:26, 17 March 2011 (UTC)

Try the .^ notation, which performs element-wise exponentiation. Octave uses vector syntax to make element-wise operations explicitly different than vector-operations. More information on this at the Octave Manual - Arithmetic Operations section or this Octave Info Page on operators syntax, from Freie Universität Berlin. Nimur (talk) 07:01, 17 March 2011 (UTC)

Thanks - the .^ notation worked, but now it outputs the fifty numbers in the format from 2.0000e+000 to 2.8147e+014. How do I get it to display the numbers in full? Thanks again. Rocketshiporion♫ 08:54, 17 March 2011 (UTC)

I figured it out myself - I have to use format long. Rocketshiporion♫ 09:15, 17 March 2011 (UTC)

Sending an unidentifiable link

Suppose I want to send someone a link to a music video on YouTube, but I don't want them to able to know the artist as they're listening to it, I want to them to remain in the dark about who they're listening to until I tell them who it is, is there any possible way I can achieve that? 24.189.87.160 (talk) 05:40, 17 March 2011 (UTC)

If you're a crafty person, I think it's possible to create a YouTube client that hides away this information - however, you'd have to make your friend use that or it wouldn't help at all. 212.68.15.66 (talk) 06:21, 17 March 2011 (UTC)

Or instead of sending them a link you could record the music as an mp3 file and send that to them.--Shantavira|^{feed me} 09:21, 17 March 2011 (UTC)

It's kinda hacky, but using Tubedubber to swap out the video but not the audio should work. Paul (Stansifer) 14:25, 17 March 2011 (UTC)

You'd still need to hide the YouTube interface potentially wouldn't you? Since doesn't YouTube often identify music automatically so they can tell you where to buy the song, know who to pay royalties to and stop you listening if you live in places where they lack royalty agreements? I have to agree with Shantavira here, is there any particular reason it has to be YouTube? Nil Einne (talk) 21:56, 17 March 2011 (UTC)

Yes, the person I'm sending it to is someone I know ONLY through YouTube, and I'm not about to share my email address with a complete stranger. 24.189.87.160 (talk) 05:00, 20 March 2011 (UTC)

Here's a possible solution. Go to the YouTube video you want, look at the address and find the 11-character code after v=. This is the video id. In the text below, replace VIDEOID with the video id, then ask your friend to paste this into their browser's address box.

javascript:void(function(){d=document.open();d.write('<iframe src="http://www.youtube.com/embed/VIDEOID?showinfo=0&rel=0&autohide=0&fs=0" width="500" height="46"></iframe>');d.close();}())

This will draw an small iframe that embeds the video but just shows the playback controls. Only a very tiny version of the video appears behind the middle of the red position bar. Be aware some videos don't allow embedding, so it won't work in that case. --Bavi H (talk) 01:32, 18 March 2011 (UTC)

Thanks,,) I'll try it out. 24.189.87.160 (talk) 05:00, 20 March 2011 (UTC)

See YouTube Embedded Player Parameters for other parameters you can use in the embed link. --Bavi H (talk) 01:39, 18 March 2011 (UTC)

Recording Flash 10 streaming sound

A webpage has some audio being streamed using Flash 10. How can I record this on my Win XP computer please? I'm using Firefox but also have IE installed.

Supplementary question: I don't suppose there is any alternative to Flash 10 to play streaming video? Thanks 92.24.180.239 (talk) 14:10, 17 March 2011 (UTC)

Answer to your supplementary question: It depends on the website from which you're streaming the video. Here's the page on YouTube where you can enable HTML5 video instead of Flash video. Supporting formats other than Flash is spreading because of the refusal of Apple to include Flash support in their iOS products. PS: If you're just asking whether Flash video on a website can be viewed on your computer with software other than Adobe Flash, see the "FLV players" section of our Flash video article. Comet Tuttle (talk) 16:43, 17 March 2011 (UTC)

http://www.downloadhelper.net/ http://jdownloader.org/ http://www.applian.com/download-videos/ ¦ Reisio (talk) 18:36, 17 March 2011 (UTC)

The point about Flash 10 is that the stream will not allow you to save it, as it is encrypted in some way. So the first link supplied by Reisio will not work, the second link is nothing to do with audio or video, and for the final one I believe the free trial only allows you to record the first five minutes and it probably wont work anyway.

Is there any way of saving the audio rather than the stream directly please? Thanks 2.97.215.199 (talk) 19:48, 17 March 2011 (UTC)

Not an answer, but a pointer for other editors: 2.97 is referring to a claimed method of copy protection that is mentioned on this page under the header "Content Protection". PS: Here is an Adobe white paper on this form of DRM. It made my eyes glaze over. Comet Tuttle (talk) 20:31, 17 March 2011 (UTC)

XP should allow you to record, on a wave editor, whatever sound is being output by your computer. More modern versions of Windows probably won't allow this, since Vista introduced the design decision that enforcing copy protection is more important than allowing the user to achieve things. See for instance the FAQ for Goldwave: [1] "How do I record Internet audio or the speaker output?" 213.122.0.29 (talk) 21:57, 17 March 2011 (UTC)

I've not had any problems recording the system stereo mix on Windows 7 using Audacity 82.43.92.41 (talk) 01:12, 18 March 2011 (UTC)

For systems that don't support "stereo mix", programs such as Total Recorder [2] exist, however that particular one is not freeware.

Windows management on Macs

Resolved

How are windows and applications handled on Macs? Looking at screenshots such as this, I can't seem to find any place were windows are handled, other than on the dock. --T H F S W (T · C · E) 17:28, 17 March 2011 (UTC)

Exposé (Mac OS X) is what most people use to navigate windows. With a certain trackpad gesture or key press, all of the currently open windows are tiled in front of you. You can also use the Dock to open a mini-Exposé consisting of all the open windows for a given application. A slightly less frequently used system is Spaces (software), which lets you create multiple desktops in addition. 108.18.208.188 (talk) 17:48, 17 March 2011 (UTC)

Mac OS X uses Quartz Compositor and Core Graphics to "handle" windows. (These are the Apple software that are comparable to an "X server"). Exposé is the most common user-interface to the windowing kit. Any application that wants to deal with windows or widgets will use the Quartz and Core Graphics APIs. Here's the high-level overview, Graphics Technologies; and here's the technical/programmer's reference-guide, Quartz Core Reference. Nimur (talk) 18:04, 17 March 2011 (UTC)

What exactly do you mean by "handled"? I'm not clear what you're asking about. In general, on a Mac each application has only a single instance, and the applications manage their windows individually. You switch between windows by switching between applications. --Mr.98 (talk) 18:28, 17 March 2011 (UTC)

I meant how do you tell what's open and switch between the different windows. I get it now. Thanks. --T H F S W (T · C · E) 21:22, 17 March 2011 (UTC)

It is a little different than Windows, as you can see. There are times when having all of the windows managed by individual applications is great, and there are times when it is maddening. --Mr.98 (talk) 01:21, 18 March 2011 (UTC)

Dual booting Vista and XP

Greetings,

I had Windows Vista on partition C: as the sole operating system on the computer. I created another partition (J:), and rebooted with the Windows XP installation CD inserted, which extracted the XP installation files onto the unallocated partition. When I rebooted, however, nothing happened; I had to use Hewlett-Packard's Vista restoration CD to have access to the Windows Boot Manager, which only detected Vista.

How might I boot the partition with the XP installation files on it, so as to finish installing XP? And once I'll have done that, how shall I be able to dual boot Vista and XP? Would I have to use a live CD to install GRUB?

Thank you so very much in advance for your answers,

88.189.248.66 (talk) 20:47, 17 March 2011 (UTC)

Yes, some type of boot manager is one way to go. On the other hand, if you have more then one hard disk (not just partitions on one disk), you could put a different O/S on each of those and then switch the boot drive in the BIOS start-up menu when you boot (you normally have to hit some key to jump to that). This approach might be better if you only infrequently switch, since you don't have to answer boot manager questions each time or wait for a time-out. Also, if either disk gets corrupted, you can then boot off the other O/S and use that to try to fix the bad one. StuRat (talk) 00:58, 18 March 2011 (UTC)

If the Windows Boot Manager now loads, you can simply edit its options to add XP as a boot option, you can do this by editing the boot.ini file in C: while Vista is loaded, or use run -> "msconfig", that utility will allow you to add XP as an option. Neoinr (talk) 03:17, 22 March 2011 (UTC)

Running as administrator on Vista

Hello all. I have Windows Vista running with VMware Player as a virtual machine. I downloaded ObjectDock free, and the thing is just horrible. After downloading RocketDock, I tried to delete it, but it gives me a notice that says: "Access denied: you must have permission to edit this folder". How do I get permission? --T H F S W (T · C · E) 21:21, 17 March 2011 (UTC)

Is your account [a] Standard [account]? If it is, try deleting it as an Administraitor, then see if you delete it. If you are still having troubles, make sure you are allowed to modify the folder, file etc. under propeties/permissions. General Rommel (talk) 04:18, 18 March 2011 (UTC)

I'm not sure. How could I tell? And how do I delete as administrator? --T H F S W (T · C · E) 06:08, 18 March 2011 (UTC)

At Control panel/user accounts/manage accounts - what do you have? Is your current user with administrators rights? Adrian (talk) 07:40, 18 March 2011 (UTC)

Yes, it is, but I still need permission. Permission from who, the surgeon general? --T H F S W (T · C · E) 17:14, 18 March 2011 (UTC)

That`s really strange. I don`t know if I can help further online like this. Sorry, I don`t have any other ideas. Adrian (talk) 18:36, 18 March 2011 (UTC)

When you say you tried to "delete" it, do you mean that you literally tried to delete the folder from Program Files? Did you try using the Control Panel's uninstall feature, or running the program's uninstaller from the Start Menu if it has one? -- BenRG (talk) 21:27, 18 March 2011 (UTC)

Sorry for not responding, I mean, right click on the folder/fine, select properties and select security. I have to say though I cannot believe you can't delete the file. As suggested by Ben, have you tried running the programs uninstall program or tried uninstalling the program from the Control Panel? General Rommel (talk) 02:27, 20 March 2011 (UTC)

March 18

Running two devices from a single ethernet cable

IS there some sort of device where I could plug in an ethernet cable and somehow be able to connect two devices to the internet at the same time? I am some three floors above the router, which is only wired anyway, so wireless networking is not an option. Powerline networking could be an option but I am unwilling to buy the extra kit. I think I've seen a device that you can plug an ethernet cable into and it can transmit a shortish-range wireless signal, but I'd rather both devices be connected with wires. Running a second wire through the walls is also problematic. Is there anything I could buy that would help? Postrock1 (talk) 00:01, 18 March 2011 (UTC)

You need an ethernet hub. You connect the original one wire to the upstream port of the hub, then connect two Cat5 cables at one end to your two devices and at the other end to two of the downstream ports on the hub. Rocketshiporion♫ 00:38, 18 March 2011 (UTC)

Fantastic that's exactly it, thank you! Postrock1 (talk) 00:45, 18 March 2011 (UTC)

You can use an ethernet hub, or an ethernet switch (which is more common in stores nowadays). Hubs and switches are different types of devices; both require a router on the "upstream" or "uplink" connection in order to function correctly. For almost all users, an ethernet switch is the better choice (better performance in general, due to "technical details" described in our article). For your purposes, you should just plug in the ethernet into the "Uplink" port, and then you'll have something like four or eight available jacks to plug in ethernet cables. Switches cost in the neighborhood of $20 or $50, though "huge" 128- or 256-element switches can cost thousands of dollars.

If you have special networking needs, it is also be possible to use a network gateway or router. This choice isn't usually a good idea, because it can cause problems for the upstream network and a headache for you (especially if you're not familiar with network address translation details). Nimur (talk) 00:49, 18 March 2011 (UTC)

Two more options:

• Many network cables have eight wires, you only need four for a network connection. So you could connect a splitter to both ends of the cable (note that you also need one at the router side) and run both connections through one cable.
• If one of the computers have two network adapters you could use that to share the internet connection with the other one. This should in principle also work using a wireless "ad hoc" network, but maybe hard to set up (and unsecure). Jørgen (talk) 08:12, 18 March 2011 (UTC)

Note that you need all eight if you want GbE Nil Einne (talk) 22:51, 18 March 2011 (UTC)

Unable to Install Adobe Flash Player

I am unable to install adobe flash player. Here is what happened:

1. I went to the official website and clicked install and followed all the steps. 2. A message installation complete came up. 3. I went to youtube and could not access any videos because youtube claims "you need the latest version of flashplayer to view this video". 4. I rebooted my computer several times, restarted internet explorer several times.

I have tried numerous pages (including games and videos for example) that direct me to the adobe flash player website. I download it and "installation complete comes up". It's even there on my list of installed programs in "control panel". But I cannot see it anywhere on my computer (it's not on my desktop, for example). And all websites tell me I haven't got it installed. I have no idea what the problem is and why it's not installing and why it's not showing up on my computer.

I would be extremely grateful to anyone who could assist me in this regard by telling me how I could download flash player so that I can actually access videos and games.

Thanks. I am using Windows 7 and internet explorer 8 if that's relevant. I have tried to download adobe flash player about 40 times and it always says "installation complete" but no adobe flash player is there on my computer or else I would be able to see youtube for example and all websites tell me I haven't got it installed. Just to emphasise I have rebooted my computer numerous times. —Preceding unsigned comment added by 121.127.207.39 (talk) 03:45, 18 March 2011 (UTC)

First I would like to recommend a different browser, but if you insist on IE , ok. Are you sure you closed all applications that might use Flash before the start of the installation ? Adrian (talk) 07:25, 18 March 2011 (UTC)

Does the "Install Completed" message come up immediately, or after it goes through several minutes of moving progress bars and such ? If it comes up immediately, I suspect that you have a registry entry that says it's already installed. Have you tried to uninstall it ? That might remove whatever remnant (like a registry entry) is preventing the install. Then you might be able to get a clean install. StuRat (talk) 07:42, 18 March 2011 (UTC)

Have you considered updating to IE 9? Chaosdruid (talk) 09:29, 18 March 2011 (UTC)

Yes, I closed all applications before installation and it goes through several minutes of moving progress bars. In fact, just in case, I did try a week ago to uninstall it and install it again but the same problem occurs. I noticed there was a forum where a number of people noted the same problem but no-one had a solution. BTW, I have another computer where I have got Adobe flash player installed and it works but that's on the other side of the country and I need to use this computer here. BTW it's an "ACER" computer if that's relevant. —Preceding unsigned comment added by 121.127.207.39 (talk) 10:03, 18 March 2011 (UTC)

I have 64 bit Vista, and was unable to install Flash on 64-bit Internet Explorer. I've not tried recently, but this may be your problem. I find it a useful way of avoiding Flash. If I want to see Flash content, I also use 32 bit Firefox, and have installed it on there. --Phil Holmes (talk) 10:08, 18 March 2011 (UTC)

Try a different browser. There are many that are more than all-right(by my opinion way better than IE), like Mozilla Firefox, Opera, Google Chrome. That are the 3 giants, and they are all great. Try one of them.Adrian (talk) 18:44, 18 March 2011 (UTC)

Please tell me how I can install adobe flash player successfully in internet explorer 9 which I have downloaded. I am afraid that no-one will answer this question anymore and I have not got a solution to my problem yet. Thanks for your time. —Preceding unsigned comment added by 121.127.207.39 (talk) 08:12, 19 March 2011 (UTC)

Big bold writing won't make people any more willing to help you. In fact it is likely to make them less willing, so therefore I have removed your unnecessary formatting.

As for an answer to your question, apart from first uninstalling old versions of flash, maybe you can try uninstalling your browser too and reinstall it from scratch (ignore Adrian's dislike of Internet Explorer - there is no reason why IE in particular would not work). Ignore any beta versions and obviously you should download the new browser before uninstalling the old one. You might also have some rogue plugin/toolbar which is interfering with Flash. Lastly, when I had problems with flash and it said I needed to install flash, I found that by viewing the page source it showed me what version it was expecting as a minimum. I then visited http://get.adobe.com/flashplayer/ and made sure the required version was less then the currently offered version (today it is: Adobe Flash Player 10.2.152.32). Astronaut (talk) 10:06, 19 March 2011 (UTC)

This might not be any consolation, but I had a similar problem with Vista, IE8 and Adobe. Eventually, after several attempts at reinstallation, they decided to talk to each other and now work smoothly. Dbfirs 14:24, 19 March 2011 (UTC)

While I agree some of the answers were not that helpful, if you want help rather then just expecting someone to be able to guess your problem or tell you the whole list of things you should have tried, it's better if you check the obvious and tell us what the results are rather then expecting us to have to ask every possibility. For example does Flash show up in IE's list of plugins? If it does are you sure it's enabled? Someone already mentioned the 64 bit version and you still haven't mentioned if you are using IE64 or IE32. Are you sure you aren't using something like FlashBlock or even IE's built in settings which are blocking Flash? Are you sure you aren't running IE in safemode which disables all plugins? Have you done a simple search for things 'flash ie9 not installed' and look at results like [3] and [4] and made sure nothing there helps? Have you checked in taskmanager to make sure IE doesn't stay in the background even when nominally quit? Have you made sure only one user is running when you install IE? Have you made sure you have enough diskspace in the drive you are installing IE? Have you made sure you are running as admin with full privileges when installing Flash (it should ask but if it didn't I wouldn't presume it's going to work)? Have you made sure you downloaded the right version of Flash i.e. the IE version? Without the answers for obvious stuff like this particularly the first 5 things (list of plugins, enabled, 64/32bit version, FlashBlock/whatever, safemode and perhaps most important of all searched!) I don't think it's surprising if you question does go without a solution. Nil Einne (talk) 21:02, 19 March 2011 (UTC)

How to make small frame by frame animation with transparent background (Apple)?

Hello,

I am now using POV-RAY on my Macbook to make animations. Using the option "Add Alpha Channel", I can make PNG images with a transparent background, which looks much nicer on a slide. However, I also need to merge these images into one animation.

Using "Frame-By-Frame", and choosing Animation as file extensions when Exporting, this looks okay, but he slightly changes the colours...

I hear that this should be possible using GIMP, but then apparently I need to save this as a GIF-file, which causes problemns in Apple Keynote.

Do you have any suggestions? Many thanks!

Evilbu (talk)

If you want to make an animated GIF, use ImageMagick: convert -verbose -delay 40 -loop 0 -density 200 src*.png output.gif. If you want to make a video format like AVI, use FFMPEG: ffmpeg -r 40 -i src%03d.png -y -an output.avi -- Finlay McWalter ☻ Talk 14:37, 18 March 2011 (UTC)

When you say "slightly changes the colours", this is a problem when using GIF. GIF is an antique format, which only allows for a palette of 256 colours - that's okay for animating diagrams and smiley faces, but if you're using real continuous tones (as you probably are, given that you're ray-tracing) then the images have to be forced into a limited palette, leading to poor colour fidelity and visible dithering. Depressingly, support for a modern animated image format is poor - PNGs moving relative Multiple-image Network Graphics would be ideal, but isn't well supported by other programs (I don't know about Keynote at all). -- Finlay McWalter ☻ Talk 15:07, 18 March 2011 (UTC)

battery prices

My laptop needs a new battery, the current one is completely dead now. But I am wondering, any idea how much more it would cost to get a whole new computer than just the battery? Also where might sell just a battery, is it something only specialist shops would have? Or something I would have to order in specially even?

148.197.121.205 (talk) 16:42, 18 March 2011 (UTC)

Batteries for reasonably current models are widely available, in big-box electronic stores and by mail order. Since laptop prices run from $100 to over $10,000 and you haven't given any indication of what kind you would want, the other question is not answerable. Looie496 (talk) 16:58, 18 March 2011 (UTC)

Amazon has batteries for sale. Make sure to get one that is compatible with your laptop. - Akamad (talk) 17:14, 18 March 2011 (UTC)

I'd typically expect a new laptop battery to cost $100 or less. It might be possible to get refurbished or used batteries for a bit cheaper (of course, since batteries wear out and may degrade over time, you probably want one that's nearly new). You might also be able to get off-brand batteries from a non-reputable manufacturer for a lot cheaper, but those might be less good, or even less safe. Paul (Stansifer) 21:23, 18 March 2011 (UTC)

What the world needs now is another blogger.

On Youtube, seemingly every video blogger has great editing (sound and image effects), video quality and quick cut scenes. Is there a package I can buy at a local brick and mortar store (like a Best Buy or Target) that I can get all that stuff right in one package? Can someone suggest some better products? I tried Googling this but I guess I wasn't entering the right keywords cause I got nothin'. Thanks in advance. --Endlessdan (talk) 17:47, 18 March 2011 (UTC)

A quick glimpse at Amazon.com shows there are tons a good webcams for cheap, so if there is a good video editing program what would it be? --Endlessdan (talk) 17:54, 18 March 2011 (UTC)

What's your budget? See List of video editing software. Adobe Premiere is the standard, but it's pricey. Comet Tuttle (talk) 18:15, 18 March 2011 (UTC)

Adobe Premiere, Final Cut Pro, and Avid are the three major software programs/suites I see most professionals using, but you can get very good results with something like iMovie or Windows Movie Maker. The quality of the video requires a decent camera, but is often dependent on the lighting and placement of the camera more than the actual quality. The same goes for video editing software. Knowing how to use your tools effectively is more important than having the right tools. Of course a high end camera, amazing microphones, and a multi-thousand dollar video editing package is great, but if you don't know how to use the equipment to its full potential using consumer grade budget equipment will be your best investment. 206.131.39.6 (talk) 18:31, 18 March 2011 (UTC)

If you're into free software, I've heard some praise about a program called Avidemux for video editing. Zakhalesh (talk) 19:12, 18 March 2011 (UTC)

Avidemux is great but very basic in terms of editing features. It's more of an encoding program 82.43.92.41 (talk) 19:37, 18 March 2011 (UTC)

I don't know myself, haven't used it, except for a very brief period when my media player was broken and I needed some substitute... and there was Avidemux. One of my friends said it's good but I'm not sure on what did he exactly use it for. Zakhalesh (talk) 20:38, 18 March 2011 (UTC)

Weird network problems

Hello. I had to replace my older Linux for Windows 7 recently. Now, I'm having network problems that no one in the same network experiences. The network connection never seems to disappear but gets REALLY slow frequently (I had to wait 5 minutes to get this form to load) while being lightning fast otherwise. I installed Wireshark (guess how long that took because of these problems) and checked what could be bugging it - it shows "Bad TCPs" at high concentrations whenever the network stops cooperating. Anyone know why's that and how to fix it? Zakhalesh (talk) 18:05, 18 March 2011 (UTC)

Is your computer powerful enough to run Windows 7 effectively? Looie496 (talk) 18:14, 18 March 2011 (UTC)

I don't remember having problems a year ago when I had Win7 the last time, and since then, I've managed to get my hands on some good hardware like a new PSU. However, I might have not noticed the network problems the last time because everyone's connection used to suck back then. I'm now on my laptop, by the way, and everything's going smooth... Zakhalesh (talk) 18:20, 18 March 2011 (UTC)

If I were diagnosing this, I'm afraid I would do the dumb-o brute force diagnosis of buying a new wired Ethernet card, installing it, disabling the built-in Ethernet networking with Device Manager, and seeing if that resolves the problem. Comet Tuttle (talk) 21:30, 18 March 2011 (UTC)

Have you tried a different cable (and if part of the cable connecting you to the router or switch or whatever is fixed a different location where the cable is known not to have such problems) Nil Einne (talk) 22:47, 18 March 2011 (UTC)

Sorry, forgot to mention that the network is wireless. Zakhalesh (talk) 12:45, 19 March 2011 (UTC)

Then the first thing you should try is using a cable. How far is your computer from the router? Are there walls between? Is there other equipment nearby that is causing interference? Windows 7 will tell you the wireless signal strength. Possibly you might need to try a new wireless card? Am I correct in assuming that your laptop has no difficulty in connecting to the router by wireless? Dbfirs 14:18, 19 March 2011 (UTC)

Cable is difficult because there's some distance between the two and also some other obstacles. However, they can't be the cause because the same computer from the same location used to work flawlessly before. Yes, no other machines on the network share the problems - my laptop works fine. I won't rely on Windows' signal strength because it won't even realize when the connection is down, still trying to tell me that the signal is "excellent" as when working. Zakhalesh (talk) 16:02, 19 March 2011 (UTC)

Sounds like a problem with the Wireless network interface controller then. I assume that you've tried resetting it. If you are sure that the settings are unchanged from when it worked previously, then try a replacement. Before you spend money, do check that there is no electrical equipment interfering with the transmission, and that the "excellent signal strength" is not from some other transmission (such as a wireless TV transmitter). Could you borrow a USB wireless connector just to check? Dbfirs 17:27, 19 March 2011 (UTC)

Does the laptop work fine in the same location as the computer with the problem? Nil Einne (talk) 20:51, 19 March 2011 (UTC)

March 19

GNU Octave Manual - PDF Format

Resolved

  Is the 725-page GNU Octave Manual available anywhere in PDF format? Thanks. Rocketshiporion♫ 01:50, 19 March 2011 (UTC)

ftp://ftp.gnu.org/gnu/octave/octave-3.4.0.tar.bz2 octave-3.4.0/doc/interpreter/octave.pdf ¦ Reisio (talk) 02:30, 19 March 2011 (UTC)

Thank you, Reisio. That's just what I was looking for! Rocketshiporion♫ 08:28, 20 March 2011 (UTC)

Filtering Strings

I have a html file and want to delete all strings except those within <img> element. What program or method can do this job? Please give me some advices or recommendations, thank you! By the way, I am using Windows.--Merry Rabbit 05:02, 19 March 2011 (UTC)

You want a program that can do regular expressions (regex). There are many options, but I do not use any of the Windows programs. Do you have any programming editors? Those commonly have the ability to do regex search and replacement. Then, you can replace everything that is not in an img tag with nothing - deleting it. -- kainaw™ 05:20, 19 March 2011 (UTC)

I can use regexp and search the strings within img tag (<img src="[0-9a-z :\.\-\/]+">), but I failed to remove the strings that are out of img tag. --Merry Rabbit 06:27, 19 March 2011 (UTC)

What do you mean "all strings". Are you wanting to extract only things within <img> tags? If that's the case this might work (note that this is sed/perl formatting... but the first is the find, the second is the replace): s/.*?<img\s*(.*?>)<\/img>/$1/gi. If you were more specific we could be too. Shadowjams (talk) 08:05, 19 March 2011 (UTC)

Yes, I want to extract only strings within <img> tags. There are at least 5,000 strings I want to extract in the html file. So I am looking for an efficient method or software. --Merry Rabbit 15:42, 19 March 2011 (UTC)

I'm not sure I understand what you mean by "strings within img tags". If you mean a list of the attributes and their values, I've attached a Python program (which uses Beautiful Soup to parse the html) below. If you mean text between <img> and </img> tags, that isn't (at least formally) meaningful, as img is a self-terminating tag, which means </img> is (formally) meaningless.

python example
#!/usr/bin/python from BeautifulSoup import BeautifulSoup import urllib data = urllib.urlopen('http://mcwalter.org').read() soup = BeautifulSoup(data) for x in soup.findAll('img'): print str(x)[5:-2] # print the tag as a string print x.attrs # print the tag as a list of (attrib,value) tuples

The two print lines are just examples - the first just prints the tag contents, the second shows them in a parsed format suitable for further processing. Which, if either, you use depends on what you're doing. -- Finlay McWalter ☻ Talk 18:24, 19 March 2011 (UTC)

Thank you for the help. Unfortunately, I can not use python...although I want to learn. My goal is simple, just want to extract all images' URLs from the html file. --Merry Rabbit 05:03, 20 March 2011 (UTC)

Here you go:

python example'
#!/usr/bin/python from BeautifulSoup import BeautifulSoup import urllib, urlparse url = 'http://mcwalter.org' #data = urllib.urlopen(url).read() data = open('index.html').read() soup = BeautifulSoup(data) for x in soup.findAll('img'): if x.has_key('src'): print urlparse.urljoin(url,x['src'])

There are two data= lines: the first gets the html over http, the second from a local file called index.html Comment out which you don't need (lines beginning # are comments). In the file case url is the URL where you got the file from originally (it's used for resolving relative image src urls). -- Finlay McWalter ☻ Talk 18:29, 20 March 2011 (UTC)

I used Python 2.7 to run the codes but got error messages. It seemed BeautifulSoup was not installed successfully...Worse, I can not solve this problem... --Merry Rabbit 04:45, 23 March 2011 (UTC)

Traceback (most recent call last):
 File "C:\1.py", line 8, in <module>
   data = open('index.html').read()
IOError: [Errno 2] No such file or directory: 'index.html'

IE8

I recently downloaded this new IE9 thinking it will be even better than the previous version. How do I get rid of it?

So far as I can tell, mostly they have just deleted some of the useful little tools for getting around the internet easier, the little button in the corner that opens a screen with all the tabs listed across it has disappeared, the menu of recently visited sites is a lot smaller and all the little buttons for my favourite sites have gone, which makes finding for example this site take rather longer. Meanwhile, all the text has come up really big and bold, which I don't like. Although, I do like the new tabs page, with the list of sites ordered by popularity, with that little bar showing how often I visit each of them. If I could have that in place of IE8's 'new tabs page', that would be even better.

148.197.121.205 (talk) 11:17, 19 March 2011 (UTC)

When you install something like Internet Explorer, Windows usually takes a backup using the system restore utility. On my Vista system, it is located on the Start menu->Accessories->System Tools (although I have moved some things around). Take a look in there and set your system back to a time just before you installed IE9. However, this might remove some windows updates and other things too, especially if you have been running IE9 for more then a few days. Astronaut (talk) 14:35, 19 March 2011 (UTC)

So, I can't simply download the earlier version again? That would be a bit easier, I think. 148.197.121.205 (talk) 15:01, 19 March 2011 (UTC)

No, a restore is better. To re-install IE8 (if MS allows this at all), you might need to first de-install it, which might take out your bookmarks/favorites and other settings, too.

BTW, I view any updates from MS very skeptically, as I often find "new and improved" versions of their products are worse than the old ones. So it would be wise to read up on any upgrade they offer, before you risk your computer on their word that it's "better". StuRat (talk) 18:37, 19 March 2011 (UTC)

Actually after all that, I think I might give it a second chance, as it is, I'll most likely be getting a new computer soon. Instead, what I want to do now is find some way to get all the text back to normal size, at the moment on half the sites it is all in bold for no apparent reason. Then, if I can find out what is up with these 'quick tabs' or whatever that was, that seem to have disappeared, I might be happy. 148.197.121.205 (talk) 18:59, 19 March 2011 (UTC)

If you do want to uninstall it, see How do I install or uninstall Internet Explorer 9] at Microsoft. ---— Gadget850 (Ed) ^talk 19:04, 19 March 2011 (UTC)

Quick tabs are back, I found a keyboard shortcut for them, favourites bar buttons are back, and all the other clutter I never used has gone, I think I actually quite like this upgrade now, if only someone can tell my how to get the text back out of bold... 148.197.121.205 (talk) 19:22, 19 March 2011 (UTC)

Is there a customize menu anywhere? If so, see if you can change the font to something else to get rid of the bold. --Thekmc (Leave me a message) 20:05, 21 March 2011 (UTC)

Parallel computing for on-stage audio processing

I don't know much about parallel computing. Is there some way to distribute a CPU load over a number of ordinary laptop computers? I'm trying to run a Max patch for live audio processing, and the patch, by necessity, uses a lot of CPU. I imagen a system for using the CPUs of multiple computers would require a program to distribute the workload among the different machines? Does such a program exist? I've looked through a lot of articles. Pages like Beowulf (computing) don't seem directly applicable to what I need to do, but maybe I just haven't found the right page yet. Thanks, --145.116.9.163 (talk) 17:52, 19 March 2011 (UTC)

Yes, the program you are using would need to be designed for parallel computing. Also, since the speed of communications between the laptops would be a concern, this would only help if a lot of processing produces a small amount of data to be transferred.

But let's back up a bit. Why do you feel the need for parallel computing ? Is the software lagging and freezing ? If so, and if you have a multiple processor laptop, perhaps an "affinity" statement could be used to force Max Patch to use one processor while everything else uses another: [5] ? And, just in case it's not obvious, you should reboot and kill everything non-essential on the laptop, using the Task Manager, to get it to run more quickly (what's non-essential may require some trial-and-error to determine). Also, disable any automatic updates or virus scanner, and disconnect from the Internet, as all those lead to lags. StuRat (talk) 18:23, 19 March 2011 (UTC)

Some other thoughts:

1) The stage can be crowded enough, without having multiple laptops hooked together. More wires means more trip hazards, more potential interference, etc. Wireless connections can solve the trip hazard, but cause other problems, in turn.

2) Unless carefully designed, a system dependent on multiple computers would be less reliable, as it would fail if any of the components (computers or cables), failed.

3) A dedicated computer (one that does nothing else) is a better choice for something where reliable, real-time, quick processing is required. I'm not sure if there is a dedicated computer that would do what you need, though.

4) You could always do the processing beforehand, say in a recording studio, then play back that portion which requires Max Patch, at the concert, adding in the rest live. (Something like using a drum machine to do percussion.) Audiences would probably be OK with that. It's usually only recorded voices that really annoy an audience. StuRat (talk) 22:32, 19 March 2011 (UTC)

I doubt that it'd be possible to share work across multiple computers for a task like this, since latency is the precise problem that you're trying to avoid, and dividing work over multiple computers would introduce latency. The task might not even be parallelizable in the first place. Paul (Stansifer) 01:40, 20 March 2011 (UTC)

It looks like it just does some audio DSP stuff. Are you running 100's of channels or anything like that? If not, I'd just check whether your existing laptop is fast enough already. The article says that program has been around since the 1980's, and today's laptops can run circles around the mainframe computers of that era. They should be plenty fast enough for most audio purposes. If not, the next step up would probably be software that can use a desktop graphics accelerator (AMD Radeon, Nvidia Tesla, etc.) rather than a bunch of parallel laptops. 75.57.242.120 (talk) 10:27, 20 March 2011 (UTC)

Choice of CPUs

Resolved: Magog the Ogre 2 (talk) 21:55, 19 March 2011 (UTC)

I have just received a new motherboard in the mail, and I have two old CPUs sitting around. The first is an , and the second an . They both support a PGA478 socket, so I appear to be able to use either (unless I'm mistaken... the motherboard says mPGA478MT).

My question: which CPU will be better for which purposes?

• CPU 1: 64 bit, 1.86 GHz, 533 MHz (Intel SVA4H full specs)
• CPU 2: 32 bit, 1.83 GHz, 667 MHz (Intel SL8VQ full specs)

From what I can see, the only thing better about the first one is that it supports 64-bit technology. As such, it will only be better if I'm running processor intensive math programs, which I'm not. Should I go with CPU 2? Magog the Ogre 2 (talk) 21:03, 19 March 2011 (UTC)

From List of Intel Pentium Dual-Core microprocessors and the page you linked, it's apparent Intel SVA4H is in the Merom (microprocessor) line. This is the newer Intel Core 2 line which has numerous enhancements improving performance over the older Intel Core/Pentium M line it was based on and that SL8VQ is. Although the specific processor is one of the reduced functionality (primarily in FSB and cache) Pentium processors, I still strongly suspect given the minimal clock speed difference (and in fact SVA4H is faster anyway) without having actually having looked at specific benchmarks that for most purposes Intel SVA4H will perform better probably significantly in some cases. Nil Einne (talk) 21:15, 19 March 2011 (UTC)

(edit conflict)The 64 bit-ness would really matter most if you wanted to have more than 4Gb of address space (which in practice means 3.4Gb or more of RAM), and you installed a 64 bit OS to access that. Beyond that, the slightly faster FSB of CPU2 is probably more important than the negligible core speed difference. The 2400 also has twice as much L2 cache. And it has VT-x, which is helpful if you're planning on running a virtualisation environment on it. -- Finlay McWalter ☻ Talk 21:19, 19 March 2011 (UTC)

Yikes! Two different answers does not make me happy! To clarify: I have 3GB of RAM I plan on using (IIRC the motherboard supports only up to 4GB), and I already uninstalled my 64-bit OS a while ago, as it seemed to be buggier than its 32-bit counterpart (even on Ubuntu), and as my processor at the time only supported a 32-bit OS. Magog the Ogre 2 (talk) 21:26, 19 March 2011 (UTC)

Well if you have a 32-bit O/S and memory accessible from a 32-bit processor, then I'd go with the 32-bit processor and save the 64-bit for your next (presumably 64-bit) system. StuRat (talk) 21:32, 19 March 2011 (UTC)

(EC multiple times) I wouldn't say I'd disagree with FM everything else being equal. But it's not and you're comparing two different processor lines. To use a more extreme example a Pentium D (Pentium 4 Dual Core) will often be lower performing then a Pentium Dual Core (from Core 2 Duo line) even if the Pentium D has a far higher clock speed and FSB. If VT-x matters to you then this may be worth any performance loss. But if you don't care about VT-x and performance is what you care about I stand by my answer.

Unfortunately getting good benchmarks for this sort of thing is likely to be difficult since they're rather different processors I'm quite sure coming out at different times and targeting different markets so there's a far chance no one trustworthy has done reliable benchmarking comparing the two. Ideally since you have both you could carry out your own benchmarks. But if that's not possible, you can take a lot at what's out there.

For example [6] [7] you can see both processors. They're actually both visible in in each page but I couldn't work out how to highlight them both so I included both in case you have trouble finding either one. However that only gives one benchmark nor are any system or other details on how the benchmark was carried out provided.

[8] and [9] are better. Problem there is you can't compare some of the benchmarks. [10] which compares the 2 doesn't seem to show the benchmarks, no idea why. However while I can't work out a way to link to this directly, if you go [11] and choose 'select individual CPUs' you can then add 'Intel' 'Pentium Dual-Core Mobile' 'T2390' 'LF80537GE0361' (only one) then 'add to selected' then choose 'Intel' 'Core Duo' 'T2400' 'LF80539GF0342M' (only one) then again 'add to selected' you can then 'show available benchmarks' to compare the two. From my look there, it was mostly as I expected, the T2390 generally won, usually by a tiny bit sometimes by more but the T2400 did win on occasion primarily tests of memory bandwidth. Bear in mind benchmarks are not always that useful in telling you how the processor performs unless your purpose with the CPU is to run those benchmark. Also the systems details are provided and it's clear both systems are different. It's also unclear as in so many benchmarks how many repetitions were done and the system details don't tell you anything about versions particular driver versions (likely to be significant in games or otherwise where the GPU is used).

In other words not a definite answer by any means but all this does agree with my belief before I looked at any benchmarks. And I should clarify these were the first 2 benchmarks I came across, I didn't discard any. Note that in any case the average performance difference if you use a multitude of applications is unlikely to be more then 10-20%

BTW are you sure the sockets are the same? Intel socket types always give me a headache but I've had a nagging feeling these may not be the same and some of the stuff I saw in my results hasn't helped.

Nil Einne (talk) 22:14, 19 March 2011 (UTC)

Nil Einne - perhaps you can explain what the improvements would be for the first system, as Finlay disagrees based on numbers alone. Magog the Ogre 2 (talk) 21:41, 19 March 2011 (UTC)

Also, this site's benchmark says the 2390 (i.e., the first one) performs better. Magog the Ogre 2 (talk) 21:45, 19 March 2011 (UTC)

Um, none of this really matters, because your processors won't go into that socket, as far as I can see. According to my Googling results, the mPGA478MT is a socket M, whereas the PGA478 is a socket P -- similar, but not identical. Looie496 (talk) 21:52, 19 March 2011 (UTC)

If you want to know the difference between the Core 2 Duo and Core Duo lines, have a look at any decent review of the Core 2 Duo when it was introduced. I'm not sure that FM actually disagreed with my point since it seems likely he never saw it due to the EC and it's not apparent he was aware that the first one was Merom/Core 2 Duo whereas the second is Yonah/Core Duo Nil Einne (talk) 22:16, 19 March 2011 (UTC)

Right you are. Thanks Looie496. Magog the Ogre 2 (talk) 21:55, 19 March 2011 (UTC)

March 20

reliability of UDP

Yeah, I know, it's the unreliable datagram protocol. My question is, suppose I send a UDP packet (100 payload bytes, say) to some arbitrary node on the internet that is online and listening for it. What is the practical likelihood of it actually getting there? The application is a "push" subscription service with occasional notifications. I don't want the overhead of a full TCP setup, don't want the subscribers polling all the time, and the messages are too infrequent to keep a TCP connection open, and it is deemed ok if a small percentage of messages never get delivered. Thanks. 75.57.242.120 (talk) 03:23, 20 March 2011 (UTC)

The "probability" of successful packet reception depends on a lot of factors - which routers you need to use to connect from source to destination node; amount of traffic those routers are currently experiencing; what queuing or QoS mechanism they use; and so on. There's no substitute for benchmarking by monitoring a realistic, statistically-significant trial period. The percentage of dropped packets can practically range from 0 to 100 %. Nimur (talk) 06:16, 20 March 2011 (UTC)

Hmm, thanks. Well, should the probability be fairly independent in the short run, from one packet to another? And should it be the same for UDP packets as for the raw IP packets that make up a TCP session? I think the Linux kernel may keep stats on TCP retry rates, so maybe checking those numbers is basically my answer. 75.57.242.120 (talk) 06:35, 20 March 2011 (UTC)

Unless you have really peculiar requirements, I would suggest TCP. The rumored overhead of TCP is much exaggerated: there is an initial handshake which is three small packets, and each packet header is 12 bytes larger than an UDP packet header - neither of which is likely to be a problem. TCP as such does not need to be kept open; a connection can be idle forever with no packets passing in either direction. Though some firewalls may time out TCP connections, so you may want to send a heartbeat packet every minute or so. As a bonus, a heartbeat lets you detect a defunct client - which you won't get with UDP; you'll never know if a UDP client has gone away. 88.112.59.31 (talk) 10:15, 20 March 2011 (UTC)

Thanks. I thought TCP connections always time out after some number of minutes. A 1 minute heartbeat would increase traffic by orders of magnitude, if messages are only going out a few times a day (the message rate will vary by large factors). Also, TCP packets result in ack packets, so that doubles the number of packets by itself. I guess that's a reasonable point about detecting a disconnected client. I could have the clients poll ~1x a day to pick up any messages they might have missed, and stop sending to clients not heard from in a long enough while. Also I'm not sure how many TCP connections a standard Linux box can keep active at once. It would be great (probably not possible even with UDP) if I could serve ~1M clients from one box. 75.57.242.120 (talk) 10:40, 20 March 2011 (UTC)

Personally, I would expect that, all other things being equal, all your UDP packets would get through. They will only be dropped under conditions of significant overload on the routers, which is by no means a common situation. I think you are likely to lose them as often as you lose a PING attempt. That said, it might be worth putting a little reliabilty into your own protocol: "This is the current message. The last one was this number. Please ask for it if you didn't recieve it".--Phil Holmes (talk) 11:10, 20 March 2011 (UTC)

...at which point you are on your way implementing your own, most likely poorly designed, copy of TCP. Retransmit timers, "did you get that message?", "did you get my message asking did you get that?", timer-controlled queue of messages in case a client asks for retransmission, etc. That is the complex slippery slope I imagine many attempts at using UDP descend. I simply use TCP, it gives me all that for free. 88.112.59.31 (talk) 18:09, 20 March 2011 (UTC)

Good points by everyone and I hadn't thought of the PING comparison. Yes the messages will have sequence numbers, so the clients could notice if there is a gap, but I wouldn't have any UDP retransmission of any sort. The application (not Wikipedia-related) is something like a Wikipedia watchlist, where you can view the status of articles that interest you by hitting a web page. The UDP service is so you can also have realtime alerts of when a watched article changes, without having to reload your watchlist page all the time. You can always get the same info by viewing the watchlist by HTTP, and that's what you'd do if you know you missed an alert. The 1-day-timeout thing means all subscriptions expire after 24h unless renewed, so to keep getting notices you'd have to refresh the subscription (by hitting a URL) once a day. 75.57.242.120 (talk) 00:02, 21 March 2011 (UTC)

Has .gov.ly been hacked?

I've been trying to find information about the current situation in Libya directly from the horse's mouth, so I searched for http://www.google.com/search?q=site%3A.gov.ly&lr=lang_en. However, that doesn't give the desired result. The first link says "HACKED By SecurityPort.org [...] Turk tarihinde bir askeri ve siyasi basari olmaktan [...] www.mof.gov.ly/". The other websites are either 404 or "under construction". Have they all been hacked? Surely, .gov.ly must have an interest in making their side of the story known to the world? Justcurious2011 (talk) 06:51, 20 March 2011 (UTC)

All that has happened is that one single website (http://www.mof.gov.ly - the Libyan Ministry of Finance), which uses an RSS feed aggregator, has read a feed from an untrusted source. As a result of what appears to be a malicious attack, somebody has injected an internet news item whose "title" is:

<td class="news_title"><meta http-equiv="refresh" content="0;URL=http://securityport.org/islam/"></td>

And, because the MOF website does not appear to properly clean the input to its RSS aggregator, it simply includes that HTML in the page, which causes an HTTP redirect to the offender's website.

How did this happen? 1) the MOF website uses an RSS aggregator script that doesn't check and clean its input; 2) somebody (who has access to a website that the RSS aggregator sources from) noticed this vulnerability, probably by recognizing the specific RSS system, whose exploit may be published; 3) the attacker created a new news-item on their own website, whose title was the code injection.

See our article - code injection - preventing code injection with data sanitization - and secure input and output handling, for best practices that should be followed to eliminate this sort of vulnerability. Nimur (talk) 20:19, 20 March 2011 (UTC)

Incidentally, you can override the URL redirect, if you want to see the original page. In Firefox, check the box for "warn me when web sites try to redirect or reload the page". Then, visit the website at www.mof.gov.ly - which is fully intact. And if you do not read Arabic, Google's machine-translator still works (it sanitizes and therefore ignores the code-injection)! Nimur (talk) 20:34, 20 March 2011 (UTC)

Thank you, that seems to make sense for the first page. Unfortunately, I couldn't try it out since that page takes too long to respond now. Which leads me to the second question: I still don't understand why there are so few pages under .gov.ly that seem to work. Is that negligence by the domain owner, or a targeted effort by others? Justcurious2011 (talk) 20:48, 20 March 2011 (UTC)

Keep in mind the difference between the domain name system and the individual websites that are underneath the domain. Generally speaking, each web site is operated independently - it has its own DNS name, its own server hardware, and probably has its own staff responsible for system maintenance and web content.

Now, I am not sure which Libyan government website would be the authoritative news website. Our article, Media of Libya, lists several state-owned newspapers, including, for example, The Republic. Their website is updated daily, and does not appear to have been compromised in any way. So you can read the Government story at that website. (Today's top headline - The people of Libya call for the killing to end. If you do not read Arabic, you may be out of luck - but of course, that newspaper is not targeting your demographic). It does not appear that any foreign agent, state-sponsored cyber-warfare, or "internet vandal" has yet managed to pull the plug on those Libyan Government newspapers.

You asked why so few Libyan government websites seem to be working. Having lived through a few rough spots in my day, I can tell you that trying to get professional workers to show up at the office and "fix computers", "write articles," and so on, while the city streets outside are unsafe, is not an easy job. If I were a Libyan government minister, and I wanted to make sure my side of the story was coming across, I would worry more about making sure my staff felt safe in their work environment, and keeping basic infrastructure (such as the plumbing, electricity, telephone, and roadways) operational. When the airstrikes get a little closer to Tripoli, those problems will be a lot harder to address. This "cyber war" nonsense is really laughable; some script kiddie in Turkey can shut down a website, but who cares? Bombs are literally falling. There are bigger problems for the Libyan government agencies than playing around with their websites. Nimur (talk) 21:54, 20 March 2011 (UTC)

Good points by Nimur. I heard that during the Egyptian street protests last month, the Egyptian middle and professional classes were quite interested in what was going on, and they followed developments mostly by sitting around at home reading the internet. They might have felt sympathetic but they basically did nothing, leaving actual protesting to the plebes. Then the Egyptian govt shut down the internet in Egypt, hoping that stopping online communications between the protesters would make the protests go away. What happened instead was that the "armchair" observers now had no way of finding out what was going on other than getting out on the streets themselves, which they did. So the internet shutoff made the protest got bigger and more respectable, rather than smaller and more marginalized. 75.57.242.120 (talk) 23:47, 20 March 2011 (UTC)

Thank you both, and especially thanks for the link to Media of Libya! BTW, as of now, no English state owned website listed in that article seems to be working. jamahiriyanews.com contains only sponsored listings (one of which claims it's from Al-Jazeera, although that seems fishy), and azzahfalakhder.com is "forbidden". But the Tripoli Post is alive and well and outspoken, with headlines such as "Despite Declaration, Pro-Al Qathafi Forces Reported Pushing into Benghazi". Justcurious2011 (talk) 07:15, 21 March 2011 (UTC)

Tracking Flickr images

Is it possible to deduce the "profile page" of an image on flickr from the file's URL? Trying to find licencing details etc. for http://farm3.static.flickr.com/2068/1791811909_acc666f314.jpg, and TinEye can't find it. Thanks! 83.70.250.202 (talk) 17:33, 20 March 2011 (UTC)

Yes, use the api. Go to http://www.flickr.com/services/api/explore/ , from the url you've given - the photoid is 1791811909 and the secret is acc666f314. The XML output generated gives all sorts of information about the image and the uploader. Nanonic (talk) 17:57, 20 March 2011 (UTC)

Evolutionary algorithm for music

Some years ago I heard on the radio about a computer program that would play a simple tune or rhythmn. If you told it that you like that tune, it would offer variations of it to you. Thus the tune evolved into something you liked.

The interesting thing was that just telling it you liked something - yes or no - was sufficient, even though there must have been many variables involved to specify the music.

I would like to play with or program something like this myself. Does anyone have any more details about it, of how it worked etc? Thanks 92.28.241.202 (talk) 17:54, 20 March 2011 (UTC)

Evolutionary music seems to be relevant. 92.28.241.202 (talk) 18:06, 20 March 2011 (UTC)

Maybe this? It's the first answer over at Wikipedia:Reference desk/Miscellaneous#Internet_song_generators and seems to be exactly what you're looking for 82.43.92.41 (talk) 18:35, 20 March 2011 (UTC)

I worked on a paper from the early stages of evolutionary music. As with much artwork, what humans find pleasing is Zipf distributed frequency of items and events. You can read the whole paper here. Notice that this paper is about writing a program that decides if music is pleasing or not. The next step (which I had no part in) was writing music that would be pleasing. -- kainaw™ 21:33, 20 March 2011 (UTC)

Awesome paper, Kainaw. I wonder if you could tune the aesthetic evaluation algorithm with a supervised machine-learning algorithm, and then run the music-synthesis step to numerically optimize for "most pleasant" music. Nimur (talk) 22:08, 20 March 2011 (UTC)

That was done later. That is an old paper - from undergrad school. I also tried it with artwork. The problem is that measuring how pleasing certain metrics are is the easy part. Defining the metrics is hard. If you miss an important metric, you'll never get anything that sounds (or looks) pleasing. -- kainaw™ 22:29, 20 March 2011 (UTC)

I think 82.43.92.41 meant WP:RDM, the miscellaneous-topic reference desk. David Cope has done some nice work in automated composition that might be thought of as a fancier version of what you're asking for. He can configure his software to generate music in the style of classical composers like Bach, Brahms, etc. He had it generate 5000 fake Bach cantatas that you can download, and I've listened to a few of them. They are pretty convincing imitations if you listen to 15 or 30 seconds at a time: they use the rhythms, harmonies, etc. that a Bach listener would expect. The problem is that they are like a computer-generated novel with good sentences but no plot. They don't really go anywhere, and after a minute or two they stop being interesting. 75.57.242.120 (talk) 21:50, 20 March 2011 (UTC)

I fixed the link 82.43.92.41 (talk) 22:16, 20 March 2011 (UTC)

Computer self restores

I'm running an older computer (Pentium D) with Windows 7 and it's not on a UPS. Earlier today I had a Wikipedia page open for editing along with a text editor and AWB both running and none of them had been saved. I got called away and after 15 minutes the computer went to sleep. I was going to go back to it when the power went out. I decided not to restart for a couple of hours and when I did I was again called away just as I pressed the power button. This time when I got back I found that the computer was in exactly the same state as before the power outage. Firefox was still open as was the text editor and AWB all with the stuff I had been working on. Why would it being in sleep mode cause that to happen? I wouldn't have thought that the CMOS battery (see below for a question about that) would have been able to have kept the information for a couple of hours. Of course I have now taken the panels off the computer to see if there is anything else that would supply power like that and there appears to be nothing. CambridgeBayWeather (talk) 23:02, 20 March 2011 (UTC)

The CMOS battery is a tiny, weak, watch battery. It barely keeps alive a little quartz clock and a few tens of bytes of BIOS settings. It doesn't (and doesn't try) to keep the main system DRAM alive. What happened is that your computer first went into sleep mode, which means it was really still "on", but with some peripheral parts of the system powered down (but with the DRAM fully powered). At some later point it switched to hibernate, which means it wrote the state of the DRAM to a file on the disk and then fully powered the machine off. Some point after that your power died. Later you returned, fixed the power outage, and pushed the "power" button. The system booted, noticed that it had shutdown as hibernate, and so restored the hibernate file into DRAM. -- Finlay McWalter ☻ Talk 23:28, 20 March 2011 (UTC)

A slight correction: for a machine as new as yours, the BIOS status is probably written to Flash memory rather than NVRAM, so the battery only has to keep the clock ticking. -- Finlay McWalter ☻ Talk 23:30, 20 March 2011 (UTC)

Firefox saves its entire state (as best it can) when it shuts down irregularly, and automatically tries to restore that state when it restarts. Looie496 (talk) 23:41, 20 March 2011 (UTC)

It's worth bearing in mind that the "power button" isn't really what it used to be. In times of yore it was a real power button: pushing it toggled whether electricity flowed to the transformer, and pushing it when the machine was on was much the same as just yanking the power cord out of the wall. But now it's just a (albeit special) button; it sends a signal that's received by the OS, which decides how to handle it. Typically the OS will push the PC to a different ACPI state, depending on how it's configured. So it means "please shut down nicely, or something", rather than being a hard kill. Incidentally the OS isn't the only recipient of this message; the ACPI microcontroller (which is in the southbridge) is also listening; that's what turns a PC "on", and generally if you hold the power button in for 5 seconds the ACPI controller figures that the OS must be misbehaving and does a hard poweroff for you. You shouldn't do that unless things have really broken, as that's to a full, unannounced, poweroff with no work saved. -- Finlay McWalter ☻ Talk 23:46, 20 March 2011 (UTC)

Looie496's explanation is the correct one, I'm pretty sure: Firefox cached what you were doing on disk while you were working, and restored the stuff from cache when you restarted the browser after the power outage. 75.57.242.120 (talk) 23:50, 20 March 2011 (UTC)

Windows 7 has a feature called Hybrid Sleep, which means when it goes to sleep it also hibernates (saves session to disk) in case of a power cut. The situation you describe is exactly what Hybrid Sleep was intended for. 82.43.92.41 (talk) 00:37, 21 March 2011 (UTC)

Thanks all for the excellent answers. CambridgeBayWeather (talk) 02:12, 21 March 2011 (UTC)

CMOS battery time of day

When I was looking for an answer to the above I looked at Nonvolatile BIOS memory#CMOS battery which says that, "These cells last two to ten years, depending on the type of motherboard, ambient temperature and the time that the system is powered off". So why does the time of day have anything to do with battery life? CambridgeBayWeather (talk) 23:02, 20 March 2011 (UTC)

Maybe it means "the amount of time the system is powered off". Meaning the total amount of time over the lifetime of the battery that the system is powered off, as opposed to the time of day (each day) that the system is powered off. Maybe it is just not written clearly. Bus stop (talk) 23:17, 20 March 2011 (UTC)

Yes. The assumption is that when the PC is switched on, the clock is powered from the PSU rather than the battery, so the drain on the battery is proportional to the proportion of the day that the PC is off. Building a circuit that's powered by two unrelated and dissimilar power sources is slightly tricky, so in practice the battery is probably still partially loaded even when the PC is powered. -- Finlay McWalter ☻ Talk 23:35, 20 March 2011 (UTC)

Thanks folks. I'm going to clarify that sentence. CambridgeBayWeather (talk) 02:13, 21 March 2011 (UTC)

Microsoft Excel 2007 linking automatic updating

I have several finance worksheets (sheet2, sheet3, etc.) in the same workbook (e.g., banking sheet2, saving sheet3, credit card sheet4, etc.). In the first worksheet, sheet1, I am trying to create a balance sheet that links to the other worksheets. In sheet1 cell B5, I have the linking string ='Sheet3'!A4. When I move Sheet3, cell A4 around within the same worksheet, I would like the contents of sheet1 B5 to automatically change to follow the move. ='Sheet3'!A4 doesn't change when I move Sheet3, cell A4 around within the same worksheet (Sheet3). Is there a linking code that I could use in sheet1 cell B5 that will automatically change when I move Sheet3, cell A4 around within the same worksheet? Thanks. -- Uzma Gamal (talk) 23:19, 20 March 2011 (UTC)

Hum, I think adding dollar signs -- ='Sheet3'!$A$4 -- might do the trick. -- Uzma Gamal (talk) 23:35, 20 March 2011 (UTC)

Actually, I meant "move" Sheet3, cell A4 by sorting Sheet3 by dates. Sometimes, the cells in Sheet3 do not return to where they were as new information is added and Sheet3 is sorted. Using ='Sheet3'!$A$4 for sheet1 cell B5 and inserting a line above Sheet3, cell A4 moved Sheet3, cell A4 to Sheet3, cell A5 and automatically revised ='Sheet3'!$A$4 to read ='Sheet3'!$A$5. When I sorted Sheet3 that resulted in Sheet3, cell A4 being located in Sheet3, cell A23, ='Sheet3'!$A$4 did not change. Is there a linking code that I could use in sheet1 cell B5 that will automatically change when I sort Sheet3, cell A4 within the same worksheet? -- Uzma Gamal (talk) 23:44, 20 March 2011 (UTC)

You could try using the INDEX and MATCH functions. You need some kind of indentifier in each row. Let's insert a column at the beginning of sheet3, so the identifiers are in column A and the data you want is now in column B. Let's say the identifier for the row you want is "foo". Then in Sheet1!B5 you put a formula like "=INDEX(Sheet3!B2:B100, MATCH("foo", Sheet3!A2:A100,0))". Look the functions up in the Excel help files for more details of how to use them. --Tango (talk) 23:52, 20 March 2011 (UTC)

Wow! Thanks. That helped out. -- Uzma Gamal (talk) 02:58, 21 March 2011 (UTC)

March 21

Safe file update (against power failure)

Is it true that in NTFS partitions, updating a file using the following method …

1. write new data to a temporary file, then
2. close the file to flush the data, then
3. move the temporary file to the original file, replacing it.

… is safer than the following method (the traditional method), …

1. truncate the file, then
2. write new data to the file, then
3. close the file to flush the data.

… power-failure-wise. I use the second method in my program, but a few days ago a power failure struck in the middle of an update, and upon powering up the computer, I got a file that contained only a fourth of the data, necessitating recovering the file. Of course I know that if I wanted greater safety, I should use continuous automatic backup, store the data in a database, install a UPS, etc., but that seemed overkill for my little program (it is not life-critical and the data is not very valuable either). 118.96.160.247 (talk) 01:00, 21 March 2011 (UTC)

I'm not a filesystem expert, but I believe that the the first method is indeed safer. It ensures that one version of the file is always on disk, and, since NTFS, like all modern filesystems, is a journaling filesystem, the file move operation will effectively be atomic, so the filename will always point to either the old or the new version. I think this method would be safer even in a non-journaling filesystem, because it means that you'd no longer be risking data loss in the event of power loss during the "write new data" step, which is probably the longest one. Paul (Stansifer) 15:58, 21 March 2011 (UTC)

What is this site up to?

For some reason I keep running into the site of some company in the UAE when looking for Google Image results showing maps of the Mexican drug cartels. The site [12] leads me to (http:) //mwjwbrfy.co.cc/fast-scan/ (a site on Wikipedia's blacklist) which has source code mentioning all kinds of "antivirus" terms and file names. How is it supposed to check these, and what does it do with them? Wnt (talk) 02:43, 21 March 2011 (UTC) [note: I was running NoScript and didn't allow the second link ... I don't know if it would be a good idea]

It's a bunch of obfuscated javascript that runs when you load the page, a standard malware technique. Looking at the code, it seems to pretend to be a virus scanner checking for and finding various viruses. It advises you to click a link to disinfect your system, and clicking the link (or any of the links on the page) downloads a .exe that is presumably evil. Blacklisting is obviously appropriate. 75.57.242.120 (talk) 03:47, 21 March 2011 (UTC)

Ah, so it doesn't have any way to look at these file names - just pretends to. Thanks! Wnt (talk) 03:55, 21 March 2011 (UTC)

As for Google image search leading to other pages, I asked a similar question last year. It was apparently the result of 'cloaking' and caused quite a stir at Google last year (see: this discussion and this one too). However, Google have take some action and my original search is now listing 'proper' sites. Astronaut (talk) 06:02, 21 March 2011 (UTC)

How do I view performance of individual cores ?

I have a quad-core CPU, running Windows XP, and I would like to view the activity on each core. When I go to the Task Manager and choose the Performance tab, I only get one graph for CPU usage. So, how do I break it down to see all 4 cores, individually ? Also, is the graph shown the total activity on all 4 cores ? StuRat (talk) 08:17, 21 March 2011 (UTC)

Open the Task Manager, switch to Performance tab, then select View → CPU History → One Graph Per CPU. 118.96.160.247 (talk) 08:27, 21 March 2011 (UTC)

Nothing seems to occur when I do that. Incidentally, that's the only choice under View → CPU History →, so presumably it was always selected. What was supposed to happen ? StuRat (talk) 08:35, 21 March 2011 (UTC)

Then Windows is only detecting a single non-hyperthreaded processor with a single core. Can you post the contents of your computer's BOOT.INI file? 118.96.160.247 (talk) 08:43, 21 March 2011 (UTC)

I can't seem to find it, even when I include hidden files in the search. Where is it normally located ? StuRat (talk) 09:11, 21 March 2011 (UTC)

Follow these instructions to open boot.ini in Notepad, then copy-and-paste into the Wikipedia edit box. (I think it's in the root directory, but you'll probably have an easier time with those instructions.) -- BenRG (talk) 09:40, 21 March 2011 (UTC)

OK, thanks, here it is:

[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP Professional" /fastdetect /NoExecute=OptOut

Perhaps there's a more fundamental problem, that it's really only using one of the four cores ? It's supposedly a 2.8 MHz GHz machine, but seems downright slow. If I'm only getting 700 MHz out of a single core, that might explain it. StuRat (talk) 10:26, 21 March 2011 (UTC)

Windows is indeed only detecting a single "processing unit" in your computer. By "processing unit", I mean a single core if you have hyperthreading disabled or half-a-core if you have it enabled. 118.96.160.247 (talk) 10:37, 21 March 2011 (UTC)

How can I tell if it's enabled or disabled ? StuRat (talk) 10:56, 21 March 2011 (UTC)

In other news, there seems to be no problem with your BOOT.INI file. Actually, I am looking for /NUMPROC and other strange options that might cause Windows not to detect all the processors, but there is none of them. 118.96.160.247 (talk) 10:38, 21 March 2011 (UTC)

Is it running with Service Pack 3 and all the Windows updates? I'm still researching, but as far as I know Windows XP didn't originally have multicore support and it was added in later, but I could be wrong there. Just trying to verify when it was added if it wasn't in there from the start. Although that leads onto another question, although Windows XP has always had multi-processor support, was this computer installed with this processor or did you install it with a different (single core) processor and then swap in this one? I ask because if that was the case then you'll have a HAL for a single processor only and that's why you're not getting multicore support. I've heard of people swapping files around to hack it to work, but the Microsoft official solution used to be that a full reinstall was needed to change the HAL to multicore. I don't know if that's still the case (I don't really work with XP much anymore so I accept I could be wrong!), but that may still be the issue. Sorry no real solution, but hoping that's at least thrown out some ideas!  ZX81  ^talk 12:21, 21 March 2011 (UTC)

This is a "refurbished" computer, meaning it's had the hardware and software updated, and was then resold. It's possible they updated the hardware to multi-core after they installed the O/S. How can I tell if I have a "HAL" for a single core ? Also, I do have Service Pack 3, and I believe I have all Windows updates except one I didn't want, which disabled booting from a USB device. StuRat (talk) 17:45, 21 March 2011 (UTC)

Apparently (I had to look it up, but I've found an old XP machine and it seems to work) if you load up registry editor (Start -> Run -> regedit) and navigate to: HKEY_Local_Machine\System\CurrentControlSet\Enum\Root\ACPI_HAL\0000 you'll see a HardwareID value there and you need to check what it is. Although there are three things it could be, you're only likely to have either acpiapic_mp (multiprocessor) or acpiapic_up (uniprocessor) which should answer that for you.  ZX81  ^talk 18:33, 21 March 2011 (UTC)

My registry doesn't quite match what you describe. I have two branches:

HKEY_Local_Machine\System\CurrentControlSet001\Enum\Root\ACPI_HAL\0000

HKEY_Local_Machine\System\CurrentControlSet003\Enum\Root\ACPI_HAL\0000

But neither of those contains a "HardwareID". StuRat (talk) 18:48, 21 March 2011 (UTC)

That "2.8 GHz" should be the clock speed of each core. It'd be pretty lame to add up the clock speeds of each core, because, for most tasks, you can only use one core in the first place. Paul (Stansifer) 15:15, 21 March 2011 (UTC)

Although if it really is 'a 2.8 MHz machine' I wouldn't be surprised your computer is slow. Actually I'm surprised Windows even starts. Even 95 wasn't designed for something that slow :-P Nil Einne (talk) 16:47, 21 March 2011 (UTC)

Yes, but making a computer sound 4X as fast as it really is would definitely be something that salesmen would do, if they couldn't be sued or arrested for it. StuRat (talk) 17:50, 21 March 2011 (UTC)

Go to "My Computer", "Device Manager", find the entry for the CPU and tell us what model it is. I don't know the exact sequence of icons to click but maybe some Windows user can supply that if needed. 75.57.242.120 (talk) 21:04, 21 March 2011 (UTC)

This ?

ACPI\GENUINEINTEL_-_x86_family_15_MODEL_2\_0

StuRat (talk) 01:45, 22 March 2011 (UTC)

That'll be why you're not getting more than one CPU then I'm afraid, that's simply not a multicore processor: http://en.wikipedia.org/wiki/Celeron#Northwood-128  ZX81  ^talk 02:32, 22 March 2011 (UTC)

How can you tell it's that model from the string I provided ? StuRat (talk) 03:10, 22 March 2011 (UTC)

It said Family 15, model 2 in your text string which matches up with the one in the article I linked. Also our same article says that this processor was made in speeds all the up to 2.8GHz which matches what you said at the top of this thread.  ZX81  ^talk 03:18, 22 March 2011 (UTC)

It it's 2.8 GHz on a single core, then I wonder why it's so slow ? That link says "Northwood-based Celerons suffer considerably from their small L2 cache", could that be the problem ? One place where it's really noticeable is when I go to open or close a file, and choose a different "Save in" directory at the top. It takes about 4 seconds to bring up the list, which seems painfully slow. Browser web-page loading/refreshes are also slow. My Fortran programs run quite fast in the MS-DOS command prompt window, on the other hand. StuRat (talk) 15:27, 22 March 2011 (UTC)

The Celerons are basically cut down versions of their bigger brothers (less performance, but cheaper), however they're not THAT slow. How much RAM have you got? From what you're describing it sounds very much like you're low on memory and you need to add more. When it's going slow and you're waiting for things to happen, is the hard drive light mainly turned on/hardly going out? If so (and the RAM figure is < 1Gb) then that'll likely be what the problem is and it's Paging to the disk as it's run out of real memory and that's considerably slower. How much memory XP "needs" seems to vary per person, but whilst a basic system will run quite happily on 512Mb (and even 256Mb!), by the time you've added some antivirus software/antispyware/firewall you're probably looking at needing 1Gb minimum to actually have some memory left to run other programs. Personally I say 1.5Gb just to be extra safe and allow some flexibility for running bigger things, but I fully expect other people to disagree with me and say that's over cautious.  ZX81  ^talk 19:17, 22 March 2011 (UTC)

Yea, that might be the problem. It lists the memory as 504 MB, which I assume is 512 less 8 for the built-in graphics board. StuRat (talk) 19:26, 22 March 2011 (UTC)

Filesystem operations (the "Save in" taks) are almost entirely unaffected by processor speed and cache. Hard drive speed (and, under some circumstances, memory size) is the bottleneck. Memory size is the most important thing for user experience speed under most circumstances. Paul (Stansifer) 20:48, 22 March 2011 (UTC)

Windows hosts file

I have a installation test procedure which asks me to edit the Windows hosts file, C:\WINDOWS\System32\drivers\etc\hosts, to add an alias for the local machine, i.e. to add a line like

127.0.0.1 the_alias

It then suggests testing this by typing

ping the_alias

at a command prompt. But it doesn't work.

It's as if the system is using some other hosts file, somewhere else. I can successfully invoke

ping localhost

where localhost is the other alias already in the hosts file. Moreover, pinging localhost continues to work even if I rename C:\WINDOWS\System32\drivers\etc\hosts so it can't be found (i.e., further suggesting that there's another hosts file somewhere else that's actually being used).

This is on what I thought was a reasonably clean installation of Windows XP.

I've tried rebooting. I've tried ipconfig /flushdns. Neither of these helped. I've checked SystemRoot, and it's indeed set to C:\WINDOWS\. I've used Windows Explorer to search all of C: for other files named hosts, and it didn't find any.

Anybody have any other ideas? —Steve Summit (talk) 23:17, 21 March 2011 (UTC)

Hmm, you're doing everything right, at least for a normal system. You don't need to run any commands, or reboot or restart the network, after changing the file: just like its unix equivalent, changes are actioned immediately (for new lookups). Some ideas:

• you've inadvertently introduced a corrupt character (perhaps an invisible one); try putting your alias at the very top of the hosts file.
• you're happening to use a name that's conflicting with WINS; try a different name
• something has changed the registry key \HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\DataBasePath (which should read %SystemRoot%\System32\drivers\etc by default) to something else - this specifies where files like host are to be found

-- Finlay McWalter ☻ Talk 00:21, 22 March 2011 (UTC)

Thanks, Finlay. I'd already checked for funky characters (cat -v), and the alias in question is one that works perfectly on other machines. (Also I've tried things like "blort" and "piffle", which don't work, either, so I'm decently sure the problem is not any kind of name clash.) I don't know how you knew of that utterly obscure, utterly (potentially) specific to my problem, seven-level-deep registry key, and I was delighted to check it out, but... no, it's set correctly. So still no joy. —Steve Summit (talk) 11:34, 22 March 2011 (UTC)

I've had the host file behave in unexpected ways as well. I always assumed it was caching results, but I'm not sure. Here's a tangential discussion: [13] on the issue. Here's Microsoft's discussion of the host file, which might give you some insights [14]. Shadowjams (talk) 20:06, 22 March 2011 (UTC)

March 22

HP Pavilion Laptop DV1000 (An old but brill laptop that HP made but did not seem to produce for long!!!)

Hi All,

Is there anyone who might have some idea what driver might work to get the internal microphone running again on this laptop.

It orignally came pre-loaded with Windows XP and said it was "upgradable" to Win Vista, which was upgraded and ran the internal microphone fine.

Subsequently I have upgraded to Windows 7 Home Premuim (genuine version) and since then the internal mic won't work, very annoying.

Silly thing is everything else works fantastic with Win 7, even though the laptop is quite slow processor wise, it runs just fine........

Note: the built in speakers have always worked with every version of Windows from the outset, but not this internal mic (from Windows 7).....I cannot understand why this Win version won't somehow run that internal mic? What is even stranger is that an external mic, plugged in to the input socket works fine, (which only cost $20), but it is annoyinfg me why some how I cannot get the right driver to make that internal mic work!!

Needless to say HP don't produce a Win 7 driver for this machine........typical HP!!

Any help would be very welcome!!!

Thanks whoever!!!! —Preceding unsigned comment added by 116.212.193.250 (talk) 03:10, 22 March 2011 (UTC)

Try this. [15] ---— Gadget850 (Ed) ^talk 17:32, 22 March 2011 (UTC)

Windows XP

WHAT IS THE FULL FORM OF WINDOWS XP? —Preceding unsigned comment added by 180.215.123.1 (talk) 08:47, 22 March 2011 (UTC)

I'm not quite sure what you mean, but if you want to know what the "XP" stands for it is "experience". (Writing in all CAPS is considered poor netiquette by the way, as it makes it harder to read) SmartSE (talk) 11:34, 22 March 2011 (UTC)

I don't think caps are harder to read, but they are "like shouting". StuRat (talk) 15:17, 22 March 2011 (UTC)

Our article, All caps, notes that indeed ALL CAPS IS HARDER TO READ. Comet Tuttle (talk) 16:34, 22 March 2011 (UTC)

Windows XP Professional includes a number of features that other versions of Windows XP (like Windows XP Home, and Windows XP Starter) do not have. The "Windows XP Media Center Edition" is the same as Windows XP Professional with Windows Media Center included. I hope this answers your question — if it does not, could you ask with a little more detail about the exact information you are seeking? Comet Tuttle (talk) 16:34, 22 March 2011 (UTC)

Excel questions

1) How to change a number written in words (e.g. seven hundred and seventy seven) to a numerical (e.g. 777) and vice versa in Microsoft excel 2007.

2) How to change a numerical date (e.g. 16-02-2011) to a date written in words (e.g. fifth of Feb two thousand eleven) and vice versa in Microsoft excel 2007.

3) how to create a PDF document offline. — Preceding unsigned comment added by Gopalmishra77 (talk • contribs) 09:04, 22 March 2011 (UTC)

To Q2, highlight the cells, right click and then choose "format cells" and you can change the format of dates. It doesn't seem to work for written numbers as far as I can tell. To Q3 - you should be able to use file > save as and choose .pdf as the format. That certainly works for me in recent versions of MS office. If you can't do that, search for the file format you wish to convert and pdf converter, so for example use ".doc .pdf converter". SmartSE (talk) 11:40, 22 March 2011 (UTC)

How can I find out what programs are accessing the internet?

Is there anyway to see what programs are receiving data from the internet? I'd like to know as I'm often restricted to accessing the internet through mobile networks and something eats up megabytes of data in minutes. I've already disabled updates for windows, antivirus, open office, itunes etc. and am a bit stuck as to what else could be using it. Anyone got any ideas what it could be? Thanks in advance SmartSE (talk) 11:32, 22 March 2011 (UTC)

Is this what you are looking for? General Rommel (talk) 11:38, 22 March 2011 (UTC)

I should also add that you need to scroll down quite a bit till you dee the download link General Rommel (talk) 11:39, 22 March 2011 (UTC)

Yes, that's awesome, especially as it is only 63kb! Sorry for being lazy and not reading the readme file, but is there any way to see the volume of traffic passing through each port? SmartSE (talk) 11:45, 22 March 2011 (UTC)

Or try Microsoft's own TCPview. -- Finlay McWalter ☻ Talk 11:52, 22 March 2011 (UTC)

I tried that one, and it says "netbios-ns" is both sending and receiving data over the Internet. What's it doing ? StuRat (talk) 15:15, 22 March 2011 (UTC)

netbios-ns is the Netbios name service (it's a bit like DNS), probably on port 137. You probably want to firewall that off, at least for the internet proper. -- Finlay McWalter ☻ Talk 17:06, 22 March 2011 (UTC)

You can also use the netstat command that comes with Windows.[16] ---— Gadget850 (Ed) ^talk 17:29, 22 March 2011 (UTC)

As Gadget says, netstat is the easiest way to go. At the command prompt (Run > "cmd"), try netstat -b (if you're in vist/7 it'll require you to run this as an administrator). Alternatively you can use netstat -o which will tell you the PID (and you can use task manager to match the PID to the process name). Shadowjams (talk) 20:00, 22 March 2011 (UTC)

Exiting Firefox

Usually when I exit Firefox on my system here at work (Ubuntu 10.04/Firefox 3.6.15), it exits quite OK. If I have more than one tab I am asked if I want to exit all tabs. However, Firefox sometimes asks if I want to save my tabs for next time. I can tick the box to not be asked about saving, but I'm curious about the strategy it uses to decide whether to ask if I want to save, or to ask if I want to exit all tabs. Astronaut (talk) 12:03, 22 March 2011 (UTC)

Do the tick boxes at Tools > Options > Tabs answer your question?--Shantavira|^{feed me} 12:42, 22 March 2011 (UTC)

No they don't. All I have (on Edit->Preferences->Tabs by the way) that is relevant is the option to "Warn me when closing multiple tabs". Nothing about when to ask about saving tabs. Astronaut (talk) 12:48, 22 March 2011 (UTC)

There does seem to be "something wonky" about how it exits. In my case, on Windows XP, it always asks if I want to save the tabs, but never does, no matter what I pick. On the same computer, Opera does save the tabs. Also, on an earlier Windows 98 machine, Firefox didn't seem to even ask if it should save them. It never did, if I closed Firefox normally. On the other hand, if the computer went down, then it apparently did try to save the tabs, and asked if I wanted to restore them, the next time I started. StuRat (talk) 14:55, 22 March 2011 (UTC)

GNU Octave - parfor Equivalent

  Does Octave have an eqivalent to MATLAB's parfor function? Typing help parfor at the command prompt results in an error. Thanks. Rocketshiporion♫ 13:54, 22 March 2011 (UTC)

Octave unfortunately has limited support for multi-core or multi-machine parallelism. Octave-Forge has a multicore package but I have not had luck with it. If you need parallel computing support, MATLAB has that capability. This single feature may be the best incentive, currently, to purchase a commercial MATLAB license, as the open-source community seems to be lagging behind MATLAB's technology in this area. Nimur (talk) 16:42, 22 March 2011 (UTC)

Conditional CSS

Is there a way to create a CSS rule so alphabets are italic and other characters are roman? It would be nice for doing mathematical expressions, such as:

y = 2x + 1

Is it possible? -- Toytoy (talk) 14:08, 22 March 2011 (UTC)

I don't believe CSS has any way of affecting content without markup. You'll have to process it to look like:

<span class="char">y</span> = 2<span class="char">x</span> + 1

and then do

.char { font-style: italic; }

--Sean 14:37, 22 March 2011 (UTC)

You can put the whole thing in a math style like <span class='math'>y=2x+1<span>. Then, you can use CSS to do overall styling in the math class. For character-specific stuff, you have to use JavaScript. First, get all content by class. Then, parse the strings. It won't be very easy as you'll have to climb around the DOM tree to get actual content. Then, you have to put each character into an italic class. Overall, it is a lot of work, but then it will save you a lot of work typing <i> over and over. -- kainaw™ 14:43, 22 March 2011 (UTC)

Well, it's not that much work... --Mr.98 (talk) 14:59, 22 March 2011 (UTC)

(ec) With CSS alone, no. But with Javascript, yes. Imagine that every equation was in paragraph element with the classname of "equation". The Javascript would search through all paragraphs with that classname, determine all a-z characters, and put them in italic tags, automatically. Here's a very quick and dirty example:

Extended content

<html> <head> <script type="text/javascript"> //process_equations function needs to be set to run "onload" in the body element function process_equations() { //create a variable 'p', that is an array of all paragraph (<p>) elements in the page var p = document.getElementsByTagName('p'); //iterate over all elements in the array p for(i=0; i<p.length; i++) { //if the class of this particular item in the p array is "equation" if(p[i].className=="equation") { //set up two variables -- one the text we are going to process, one a text buffer we are going to output text_in = p[i].innerHTML; text_out = ""; //iterate over every character in the input text for(x=0; x<text_in.length; x++) { //if the character (made uppercase for comparative purposes) is both >="A" and <="Z", then... if((text_in.charAt(x).toUpperCase() >= "A") && (text_in.charAt(x).toUpperCase() <= "Z")) { //the character is put into italics and put into the output buffer text_out = text_out + "<i>"+text_in.charAt(x)+"<\/i>"; } else { //otherwise, just add the character to the output buffer without changing it text_out = text_out + text_in.charAt(x); } } //finally, replace the paragraph data with the output buffer p[i].innerHTML = text_out; } } } </script> </head> <body onload="process_equations()"> <p>Here is an equation:</p> <p class="equation"> y = 2x + 1 </p> </body> </html>

The code above should be pretty straightforward to make sense of-- it iterates over all paragraphs, checks their classnames, then iterates over each character in the correct paragraphs, determines if it is a letter from A to Z (this is the ugliest part above), and if so, puts italic tags around it. --Mr.98 (talk) 14:58, 22 March 2011 (UTC)

That code assumes that there is no html inside the equation area, which I expect will not always be true. You don't want to turn something like <b> into <<i>b<\i>>. That is why I noted that you'd have to climb the dom tree, not simply parse the inner html. -- kainaw™ 16:36, 22 March 2011 (UTC)

True enough. It assumes very simple considerations — you'd have to modify it to meet your needs. But it would not be hard to make it ignore HTML tags within the inner HTML -- just a small addition of a flag that checks if we are in an HTML tag:

Extended content

<html> <head> <script type="text/javascript"> //process_equations function needs to be set to run "onload" in the body element function process_equations() { //create a flag that tells us if we are "in" an HTML tag var inTag = false; //create a variable 'p', that is an array of all paragraph (<p>) elements in the page var p = document.getElementsByTagName('p'); //iterate over all elements in the array p for(i=0; i<p.length; i++) { inTag = false; //reset this, just in case some tags were malformed previously //if the class of this particular item in the p array is "equation" if(p[i].className=="equation") { //set up two variables -- one the text we are going to process, one a text buffer we are going to output text_in = p[i].innerHTML; text_out = ""; //iterate over every character in the input text for(x=0; x<text_in.length; x++) { //first we check if this is the beginning or end of an HTML tag if(text_in.charAt(x) == "<") { //if at the beginning of a tag, mark "inTag" as true inTag = true; text_out = text_out + text_in.charAt(x); } else if(text_in.charAt(x) == ">") { //if at the end, mark as false inTag = false; text_out = text_out + text_in.charAt(x); } else { //if we are not in an HTML tag then check it... if(!inTag) { //if the character (made uppercase for comparative purposes) is both >="A" and <="Z", then... if((text_in.charAt(x).toUpperCase() >= "A") && (text_in.charAt(x).toUpperCase() <= "Z")) { //the character is put into italics and put into the output buffer text_out = text_out + "<i>"+text_in.charAt(x)+"<\/i>"; } else { //otherwise, just add the character to the output buffer without changing it text_out = text_out + text_in.charAt(x); } //if we are in an HTML tag, then just spit it out } else { text_out = text_out + text_in.charAt(x); } } } //finally, replace the paragraph data with the output buffer p[i].innerHTML = text_out; } } } </script> </head> <body onload="process_equations()"> <p>Here is an equation:</p> <p class="equation"> y = 2<b>x</b> + 1 </p> </body> </html>

Every text parsing takes assumptions about the form of the text into account. This is just meant to show that it wouldn't be very hard to set up a basic one, one that could be modified as one saw fit. --Mr.98 (talk) 21:26, 22 March 2011 (UTC)

CSS targets which content it affects with selectors. Selectors target a whole element (or a whole subtree of elements), not specific words or letters (the only exception that I can think of is the oddball :first-letter pseudo-element selector, which doesn't help you). There isn't a (sane, at least) way of selecting for the nth character of an element, or for selecting characters or words based on their content. In general CSS isn't really very expressive, and in many cases is no substitute for a server-side macro language or client-side javascript. -- Finlay McWalter ☻ Talk 15:02, 22 March 2011 (UTC)

'Amazon Online Reader' does not work in my Firefox 3.6.15

Does anyone know why this might be? Using WinXP SP3. Thanks 92.15.6.157 (talk) 14:20, 22 March 2011 (UTC)

What happens when you try ? StuRat (talk) 14:47, 22 March 2011 (UTC)

I get a message on the page in yellow saying "Your web browser does not support this feature. Please visit our Frequently Asked Questions for a list of compatible web browsers that support the Amazon Online Reader." 92.15.23.133 (talk) 18:34, 22 March 2011 (UTC)

And is Firefox 3.6.15 in that list ? StuRat (talk) 18:53, 22 March 2011 (UTC)

After following the link given, I cannot see any list of web browsers, and the word Firefox is not on the page. 92.15.10.228 (talk) 21:19, 22 March 2011 (UTC)

MSI CR410 laptop

Economic Times has reported that MSI CR410 laptop with all std features Wi-fi,bluetooth,webcam etc is less than INR 18,000//. Has anyone used it and is it worth what it says? Available only on online order form. —Preceding unsigned comment added by 59.92.77.228 (talk) 14:21, 22 March 2011 (UTC)

To others reading this question, "INR 18,000//" is 18,000 Indian rupees. At current exchange rates of about 45 per USD, that's $400. I have no idea what the "//" part means, though. Perhaps that's a way of saying there are no "cents" ? StuRat (talk) 14:52, 22 March 2011 (UTC)

Video Joining Software

Hi, I am looking for a video joining software, in order to join two separate video files. But I need a special feature. The videos that I wish to join are from a continuous event. I guess it was split into 2 files in order to reduce the file size. But the ending part of first video (maybe 4-5 seconds) is also repeated in the starting of the second file.

So, the requirement is for a software which while joining the files, also lets the user adjust how much time to overlap/clip.

Can anyone help me with providing some lead to such a software. A free/open source software would be preferable.

Thanks. — Preceding unsigned comment added by Kanwar rajan (talk • contribs) 15:54, 22 March 2011 (UTC)

Avidemux can do this 82.43.90.38 (talk) 16:04, 22 March 2011 (UTC)

(ec) The Windows Movie Maker software that came pre-installed on my Vista laptop can do this. It is a simple matter to eliminate the time overlap. Astronaut (talk) 16:05, 22 March 2011 (UTC)

Thanks a lot!! I will give it a try. — Preceding unsigned comment added by Kanwar rajan (talk • contribs) 16:20, 22 March 2011 (UTC)

Also VirtualDub. ---— Gadget850 (Ed) ^talk 17:21, 22 March 2011 (UTC)

Problem with search engines

This problem cropped up just today. When I try to use Google, Bing or Yahoo for search, all I get is a blank page. I tried a restart and that didn't work. I've also tried using various browsers, Opera, Firefox, IE and Chrome, and none worked. Google mail and Yahoo mail work fine, however. Any thoughts? Thanks. 71.125.150.30 (talk) 16:36, 22 March 2011 (UTC)

The standard first advice here is to download an anti-malware program, like Malwarebytes's offering, and scan your system to see whether you've got a computer virus or other malware that mucks with your outbound DNS queries, or the like, to redirect you to websites that the malware wants you to see. Comet Tuttle (talk) 16:38, 22 March 2011 (UTC)

A reboot is also worth a try here. StuRat (talk) 16:39, 22 March 2011 (UTC)

I tried a reboot and that didn't work. I downloaded Malwarebytes and I'm running that now on the problematic laptop. Thanks. 71.125.150.30 (talk) 16:53, 22 March 2011 (UTC)

Malwarebytes worked. Thanks for the help. I have been running Norton, provided by my service provider and updated regularly, but it failed to pick up a total of 32 infections. Interesting. Again, thanks.71.125.150.30 (talk) 17:07, 22 March 2011 (UTC)

You're welcome. May I recommend creating an account without administrator rights and using that account habitually? It makes it more difficult for malware to infect your operating system. The only downside is that it's occasionally annoying when you have to install something, or when using old software from the early days of Windows Vista or before that works poorly with non-admin accounts. Comet Tuttle (talk) 19:44, 22 March 2011 (UTC)

Windows 7

I have an old computer with no screen, keyboard or mouse running Windows XP which I can use via remote desktop connection from my Windows 7 computer. I want to install Windows 7 on the old computer. Is there a way I can go through the install process via remote desktop connection, so that I don't have to switch the screen and keyboard over and render the other computer unusable during the install? Also, the old computer only has 1GB of RAM so is installing Windows 7 on it going to be beneficial over XP, or will it function slower than XP currently does? 82.43.90.38 (talk) 17:05, 22 March 2011 (UTC)

Here are the minimum system requirements for Windows 7: [17]. 1GB of RAM is the minimum, so I'd be a bit wary. It probably will be slower. StuRat (talk) 17:13, 22 March 2011 (UTC)

"via remote desktop connection": No. You cannot perform an in-place upgrade from XP to 7.[18] Step 1 of that page links to the Windows 7 Upgrade Advisor which will identify potential upgrade issues. ---— Gadget850 (Ed) ^talk 17:20, 22 March 2011 (UTC)

I don't understand what you mean by "in-place". 82.43.90.38 (talk) 18:39, 22 March 2011 (UTC)

You cannot load 7 over XP and maintain settings and documents. You have to format your drive and do a clean install (nuke and pave). ---— Gadget850 (Ed) ^talk 18:46, 22 March 2011 (UTC)

I don't care about preserving settings and documents. You can assume there's no OS on the computer if that makes it easier. I just want to be able to go through the Windows 7 install procedure without attaching a keyboard and screen to the computer. I thought there might be the possibility of doing that over the Remote Desktop Protocol 82.43.90.38 (talk) 19:44, 22 March 2011 (UTC)

You can't install an OS over a remote desktop connection. You can create a DVD that will install the OS without any user input, but I suspect in your case this would be more difficult than doing it by hand. (It's useful for IT professionals who have to upgrade a bunch of machines at once.) Unless you have a specific reason to install Windows 7, though, I wouldn't bother. Don't install it in the hope of making your old computer faster, since that's very unlikely to happen. -- BenRG (talk) 19:29, 22 March 2011 (UTC)

I mainly want to install Windows 7 because Windows XP has trouble to coping with thousands of files in a folder, whereas Windows 7 has been able to. I certainly don't expect Windows 7 to increase the speed to the computer, but I was concerned that it might cause a significant decrease in speed since Windows 7 is a much larger operating system. If Windows 7 will perform as well as XP on the older hardware, that's good. 82.43.90.38 (talk) 19:49, 22 March 2011 (UTC)

Upgrading memory on my PC

I have 512 MB of memory on my PC (CPU = Celeron#Northwood-128, O/S = Windows XP SP3 (32 bit)), and, based on a discussion further up the page, it looks like I need more memory. I have 4 memory slots, with the following contents:

1) 128 MB DDR, PC2700U CL2.5 25331 C3 0322 4X0365 121033 P/N 305956-041.

2) 256 MB DDR, PC3200U CL3   30331 A1  400 MT8VDDT3264AG-40BG4 200424 BZACH3G002 S/C: 3804740072E PN: 326667-041

3) 128 MB DDR, (Exactly the same as in slot 1).

4) Vacant.

All 3 memory cards are labeled Hewlett Packard. Slots 1 and 2 are close together, as are slots 3 and 4. Slots 1 and 3 are black, and slots 2 and 4 are blue. Sorry for all the excessive info, but I don't know which numbers are trivial and which are critical. So, here are my questions:

A) Does the slot placement of the cards matter ?

B) Is it OK to mix and match cards, like I have ?

C) I'm thinking of getting an additional 256 MB DDR card, like the one now in slot 2, and placing it in slot 4. That would give me 768 GB of RAM. But could I put a 512 MB card or 1024 MB DDR card in there, instead (to give me a total of 1 or 1.5 GB) ?

D) What significance, if any, does the color of the slot (blue versus black) have ?

E) If I decided to go all out and put in the maximum RAM my PC can handle, what would that be ? Is it only limited by my 32-bit operating system ?

F) Can I use the faster DDR2 or DDR3 memory cards ? If so, can I mix and match those with my current cards ? StuRat (talk) 21:25, 22 March 2011 (UTC)

I'll answer the ones I can;

B) I've had no problems mixing different sizes of RAM cards on my computer

C) Yes

E) 32-bit operating systems can only address 4GB usually. You can't install a 64-bit operating system on 32-bit hardware

F) No, DDR2 and DDR3 cards are shaped differently and won't fit in the slots

82.43.90.38 (talk) 22:07, 22 March 2011 (UTC)