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March 11

"&" in command line

Does & mean anything when used at the command line in Windows? Apparently in Unix it makes a command run in the background, is this the case on Windows as well? rʨanaɢ ^talk/_contribs 06:06, 11 March 2010 (UTC)

It is usually used to put two commands onto one line. The following example moves to the root of a drive and lists its contents:

cd \ & dir

It is also used to duplicate a handle (e.g., standard error [A.K.A. STDERR or 2] or standard output [A.K.A. STDOUT or 1]). Say you wanted to list the contents of a folder and output any errors to a text file. You could type this to do that:

dir > .\list.txt 2>&1

The above example redirects the output of the dir command to a text file named list.txt. It also puts any error messages in that same file by redirecting STDERR to a copy of STDOUT.--Drknkn (talk) 06:20, 11 March 2010 (UTC)

This doesn't exactly answer the question, but might be useful: Microsoft's command line reference list [1] It doesn't include operators though.

In bash a single & will background the command, but a && is an "and" operator so it works to execute commands in succession, but maybe the more straightforward way to do it in bash is to use " ; ", which is the command separator. I'm not sure if there's ever a practical difference though (except the &&s will actually evaluate). Shadowjams (talk) 07:01, 11 March 2010 (UTC)

Bash's && short-circuits like in C-derived languages: if the first command fails then the second command isn't tried. With ;, both commands are run regardless of their exit statuses. —Korath (Talk) 07:30, 11 March 2010 (UTC)

Thanks. The one I was thinking of was the one I've seen used at the end of a command, as in

xdvi foo.dvi &

(for previewing DVI files on Unix); judging by Shadojams' comment, it sounds like the command-final & has the same function in Windows. rʨanaɢ ^talk/_contribs 16:30, 11 March 2010 (UTC)

In DOS (and the command prompt for Windows), the '&' serves the same purpose as the ';' in Linux, it's an unconditional sequential execution operator. DOS isn't multiprocess aware, so it can't run background processes. All the & says is: "When the program to the left of me finishes (whether or not it succeeds), run the program to the right of me." —ShadowRanger ^(talk|stalk) 16:41, 11 March 2010 (UTC)

Ok, that makes sense. Thanks for the help! rʨanaɢ ^talk/_contribs 17:00, 11 March 2010 (UTC)

I posted a detailed explanation of what the ampersand does in Windows. Posting detailed explanations is not something I will do again for you.--Drknkn (talk) 17:04, 11 March 2010 (UTC)

Was that necessary? Nothing he posted asked you for an additional "detailed explanation". Thanks, gENIUS101 21:39, 11 March 2010 (UTC)

You're right. I shouldn't have said that. He did nothing wrong. I apologize.--Drknkn (talk) 23:21, 11 March 2010 (UTC)

RAID stripe data recovery

I purchased a Apple Intel Tower which subsequently had a hard disk fail . The hard disks (2) in OSX (10.6) were set to a Raid stripe(?) config - now that the main Hard disk is dead... is there any way to recover any data from the 2nd striped HD ?--Boomshanka (talk) 10:16, 11 March 2010 (UTC)

Nope. If any hard drive in a striped array fails, all the data is gone. 121.72.196.8 (talk) 11:07, 11 March 2010 (UTC)

Striping RAID 0 is often referred to as "not a RAID" because there is no redundancy in the data. That is why losing a drive loses the whole thing. RAID 0 is not used for handling drive failure. It is used for drive speed - dividing large read/tasks among multiple drives at the same time. -- kainaw™ 13:33, 11 March 2010 (UTC)

Well, the term "stripe" is used in raid levels higher than 0, so it's possible you had redundancy. If not, data recovery from the failed drive might be possible, but it's an unreliable and expensive process. There are some cheap hacks that you can try though, like putting the drive in the freezer for a while, then trying to start it while it's cold. This is said to sometimes temporarily fix electronic problems for long enough for you to read the data from the drive. 66.127.52.47 (talk) 12:19, 15 March 2010 (UTC)

Windows Vista

I would like to disable users from using USB ports. How do I go —Preceding unsigned comment added by Tajadi (talk • contribs) 10:32, 11 March 2010 (UTC)

That depends on the purpose. If all you want to do is keep someone from plugging a random USB device into your personally-owned computer and getting it to connect, some scripting/ADM templates and creating a user account with limited privileges for everyday work is a simple approach. If the computer in question is part of a company network where several users need to log on, and some might even have elevated or full administrative privileges, things get a little bit more hairy, and you might want to look into one of the commercially available solutions. -- 78.43.60.58 (talk) 11:43, 11 March 2010 (UTC)

Or you could physically disable the ports, by filling them in epoxy, clipping the leads on the motherboard, etc, assuming you don't need any USB access at all (say, for keyboard and mouse). Again, purpose-dependent. —Korath (Talk) 12:21, 11 March 2010 (UTC)

That's a bit drastic. Most likely OP just wants to block mass storage devices from being used. You can do this from the control panel when logged in as administrator —Preceding unsigned comment added by Fire2010 (talk • contribs) 13:48, 11 March 2010 (UTC)

You can lock it down/configure what is allowed using Group Policy. The Microsoft page here has more information on this. Another option is to use 3rd party software such as DeviceLock which allows a lot more control over what is/isn't allowed and also locks down Windows XP machines (which Group Policy can't do). ZX81 ^talk 18:23, 11 March 2010 (UTC)

Limiting Ubuntu Hardy Heron's use of CPUs / Cores

Is there any way of telling Ubuntu that unless specifically requested otherwise, it should only use the first core (core 0) in a multi-core machine? The reason I'm asking is that I want to run virtualization software on it, and the two virtual machines have different CPU needs, so my plan would be to run the CPU-intensive VM on the second core (core 1), while running the host system and the less CPU-intensive VM on the first core (core 0). The virtualization software allows for such a setting per VM, I just haven't found a way to make the host stick to one of the two cores. Is that possible, and if so, how? -- 78.43.60.58 (talk) 11:18, 11 March 2010 (UTC)

Kinda. You can use the taskset program to set the processor affinity of a given process. So you could, with a bit of labour, set all the CPU-intensive processes in the host to CPU-A and set the virtualisation program (VmWare or whatever) to CPU-B. You can't completely banish the host from CPU-B, but this procedure should be enough to give the VM essentially all the cycles on it. -- Finlay McWalter • Talk 11:48, 11 March 2010 (UTC)

But I don't think this will, in most circumstances, turn out to be a terribly good idea. The scheduler is pretty smart, is cache aware, and knows a great deal more about the real-time characteristics of your running system than you can. This IBM article lists the very few reasons where setting processor affinity might be a worthwhile idea. -- Finlay McWalter • Talk 11:56, 11 March 2010 (UTC)

Unfortunately reason #1 from that article is "I have a hunch", which I believe is what 78 has. 74.212.140.226 (talk) 17:33, 12 March 2010 (UTC)

What? It's not that complicated. You can pass the number of cores to use as a kernel parameter at boot time. Just edit your grub menu.lst and add maxcpus=1 to the end of your "kernel" line. (Alternately, if you use maxcpus=0 or nosmp, SMP will be disabled. I'm not entirely sure what the difference is, for your purposes.) If you want to boot into full SMP mode, just reboot without that kernel option (ie, keep at least 2 menu entries in grub). If you want to do it without rebooting, well... that's complicated. Indeterminate (talk) 10:49, 13 March 2010 (UTC)

The way I understand the article you linked, that would completely disable the CPUs with higher numbers than the number specified on the maxcpus=n line. Which would mean they are out of reach of the VMs as well - obviously not what I want. :-/ -- 78.43.60.58 (talk) 15:39, 13 March 2010 (UTC)

Ah, right, this is for a host OS, my mistake. In that case, perhaps isolating the second core from the scheduler is a better option. The description claims that this works better than manually setting the affinity of all the processes. The boot option for that is isolcpus=1 (since it starts at 0). Then when you create your VM, you can move it onto the second core using taskset. The isolcpus option has apparently been superseded by dynamic scheduling domains, but that's getting way out of my comfort zone. It'll probably remain in the kernel for the foreseeable future. Indeterminate (talk) 21:26, 13 March 2010 (UTC)

That works, with one caveat (which you mentioned) - this requires manually setting the processor affinity of the VM that has the CPU-intensive workload using taskset, as VMware Server seems to be bound by the isolcpu setting as well. While you can add processorn.use = "FALSE" to a VMware config file, it will still use processor #n if that is the only one available because of the isolcpu setting. Again, not saying that you were wrong here, just pointing out a caveat in case some day someone else searches the archive for a solution to the same problem I had. It's tempting to think "Okay, I set isolcpus for the host OS, I defined the per-VM processor use in the config files, now my VMs should run on the CPUs I specified, riiiiight?" -- 78.43.60.58 (talk) 10:22, 16 March 2010 (UTC)

Upload speed

What is the minimum upload speed a server should have so that loading pages won't take too long on the other end, and a small number of users won't consume all the bandwidth and make the site unreachable? —Preceding unsigned comment added by Fire2010 (talk • contribs) 13:58, 11 March 2010 (UTC)

That depends on how many users is "small" and how much data each one is expected to consume. For a half a dozen users looking at purely static HTML pages of a KB or two in size, consumer grade DSL (768 Kbps upload) would be more than sufficient, but for fifty users on an AJAX enabled site with constant communication, or a Flash video server, it won't be nearly enough. Basically, you need to work out the peak expected upload rate (total size of X number of users download Y KB of data at the same time, divided by the number of seconds you consider reasonable for responsiveness). —ShadowRanger ^(talk|stalk) 16:36, 11 March 2010 (UTC)

Were can I find Debian 5.0.0 CD/ISO?

Resolved

Can anyone point me to an ISO of Debian 5.0.0? I spent many time searching and I find nothing. I really need version 5.0.0 and not later versions like 5.0.4. I know I can mess around with repositories and change them to older ones (or later one) and do all sort of fun things, but what I need is really the installable ISO. Thanks --SF007 (talk) 16:17, 11 March 2010 (UTC)

Just found it here! http://cdimage.debian.org/cdimage/archive/ --SF007 (talk) 16:32, 11 March 2010 (UTC)

Secret Web Page

Is it possible for me to upload information to the internet and not have it show up in a search engine? Or, are the search engines so thorough that they will find and catalog anything I post? Hemoroid Agastordoff (talk) 20:44, 11 March 2010 (UTC)

Well, with a proper robots.txt, well-configured search engines can be told not to index a site (or specific pages within the site). —ShadowRanger ^(talk|stalk) 20:50, 11 March 2010 (UTC)

If you don't link to the page, it will never be found (short of an intrusion or guess); but if you don't link to the page, some might consider the entire endeavor pointless. ¦ Reisio (talk) 20:54, 11 March 2010 (UTC)

Yes, if you have the page at a complex random URL never mentioned anywhere, not linked to from anywhere, and not linking anywhere (or at least not being used to go anywhere - otherwise the referrer field can give you away), search engines are extremely unlikely to find that page. --Stephan Schulz (talk) 20:58, 11 March 2010 (UTC)

(ec)In addition to robots.txt (which legitimate search engines respect, but which the spiders than scammers and spammers use ignore) you can exploit how search engines find your pages. Search engines collect web pages using a web crawler, which traverses the network of links inside sites. If there is no link to a page, a web crawler can't find it and won't read it. So long as you (and, crucially, anyone you tell about the page) doesn't post a public link anywhere, a crawler won't find it. In theory someone could guess the page's url and speculatively try that (bar a few common and legitimate examples, no sensible spider will resort to guessing), but you can avoid that by giving pages an essentially unguessable name (e.g. http://agastordoff.net/320894503984309482304983.html); and you need to make sure that your web host's auto-index feature is disabled (or provide a blank index for that folder). Strictly, if the content is secret or illicit, this amounts to security by obscurity, which is really no security at all - so anything that you want to protect more than just casually you should at least hide behind a password, or better yet a proper login (and transmit over ssl). -- Finlay McWalter • Talk 21:04, 11 March 2010 (UTC)

Alternatively, you could always encrypt the content itself, rather than require an SSL login. Anyone can get your data, but without the decryption key it's worthless. —ShadowRanger ^(talk|stalk) 21:05, 11 March 2010 (UTC)

This may surprise a lot of people, but most of the information on the Internet is actually not available through search engines. It's called the "Deep Web" or "Invisible Web". A search engine can't index something it can't find, so as is said above, if a page is never registered with a search engine or linked from anywhere else, it won't show up on a search engine. A website without any links that is never registered in a search engine is kind of like a pond that isn't connected to a river or any other water source--no matter how hard you try, you can't swim from any other body of water into the pond, because there's no connection. For all intents and purposes, that pond doesn't even exist to you. That's kind of a bad analogy, I know, but hopefully it makes sense.

Some other reasons why a site/information wouldn't show up in a search engine is if it's part of a password protected site (so the search engine "spiders" can't scan the site), a dynamically generated site, or if it isn't in a textual/HTML format (for example, the contents of a picture or video can't be indexed by a search engine). 24.247.163.175 (talk) 22:11, 11 March 2010 (UTC)

Many ways:

1. Set up a robots.txt file that tells search engines to exclude the content (relies on search engines to obey it... many/most do, though)
2. Put the content behind a password
3. Set up some kind of simple CAPTCHA
4. Don't link to it from anywhere else (relies on nobody else linking to the page)

Which of these makes the most sense depends on who you want to view the page more than it does who you want to keep out. --Mr.98 (talk) 22:31, 11 March 2010 (UTC)

Google also uses Sitemaps to find and index sites. If you have put one on your site, make sure that your "hidden" page doesn't appear in the sitemap list. --Phil Holmes (talk) 09:23, 12 March 2010 (UTC)

Another way is to use <meta name="robots" content="noindex,nofollow" /> in the header of the HTML file. With "noindex,follow" you probably cause search engines to follow links from your page but don't index the page itself - I think that's the classical way "google bombs" are created. Icek (talk) 18:24, 12 March 2010 (UTC)

Addendum: I meant to say that google bombs are probably created by having many pages with "noindex,follow" which link to the page you want to "bomb", with the bomb keyword as the link text. The pages then can link to each other too, without appearing on Google's results page. The linking of bomber's pages to each other may increase the PageRank. Icek (talk) 18:43, 12 March 2010 (UTC)

The safest way to go would be to password protect it, or put it behind some type of authentication firewall.Smallman12q (talk) 22:41, 12 March 2010 (UTC)

March 12

Computer unable to renew IP Address

I have until recently been successfully using a Dynalink RTA1025W wireless router for an ADSL2+ connection. It was used wirelessly for my laptop, running Ubuntu 7 and through ethernet cables to an XBox 360 and a pc and laptop running xp. I recently had the router replaced under warranty due to an unrelated hardware problem and the replacement unit will only interface with the wireless laptop and the xbox. When attempting connection with the windows computers, it says they're unable to renew their ip addresses. I have looked for this problem extensively on the Web but have never found an example of where the problem was a new router of the same model. Does anyone know of any settings for the pc or router that I should try in order to solve the problem? Help would be greatly appreciated and I'd be happy to give further details Mix Lord (talk) 07:20, 12 March 2010 (UTC)

The first thing to check is whether the DHCP server on the router is turned on. If it is, we'll see what else we can think of... --Phil Holmes (talk) 09:21, 12 March 2010 (UTC)

DHCP is on, thanks for your help

203.219.227.72 (talk) 09:28, 12 March 2010 (UTC)

This is really guesswork, but maybe the windows PCs are remembering addresses that the router has allocated to your other devices. Bring up a command prompt and type

ipconfig /release

followed by

ipconfig /renew

If that fails type

ipconfig /all

and paste the results here so we can take a look. -- Q Chris (talk) 09:40, 15 March 2010 (UTC)

ipconfig/renew takes ages then says "An error occurred while renewing interface Local Area Connection : unable to contact your DHCP server. Request has timed out.

ipconfig/all gives the following info Primary DNS Suffix................... Node Type............................Unknown Ip Routing Enabled...................No WINS Proxy Enabled...................No

Connection-Specific DNS Suffix....... Description..........................SiS 900-based PCI Fast Ethernet Adapter Physical Address.....................00-14-2A-78-3F-83 Dhcp Enabled.........................Yes Autoconfiguration Enabled............Yes IP Address...........................0.0.0.0 Subnet Mask..........................0.0.0.0 Default Gateway...................... Dhcp Server..........................255.255.255.255

Apologies if I have uploaded any sensitive information there which may make my computer vulnerable.

Definitely check the physical stuff: Is the link light on on both the back of your network card and for the appropriate port on the router? If not, try a different router port, network cable, and lastly, it doesn't hurt to re-seat the network card (unless it is onboard network, as most everything seems to be these days...). Also, if your router isn't of the "built-in ADSL modem" type, try bypassing it by plugging your PC straight into the modem. Usually, trying to find a new driver for your ethernet card/system board (whichever you have) is useful, but I think Windows 7 does a pretty dang good job of finding the best driver. It also doesn't hurt to call your provider, and provide them with your MAC address (the one labeled "Physical Adress" on your readout above). I wouldn't be surprised if frontline techs can't see this type of information (and they'll walk you through all of the "unplug and replug all of your cables, power cycle the modem etc.), but a real "tech support" type person can see if any requests are coming from that MAC address and/or if there is a restriction on it for any reason. Finally, when it all comes down to it, there's always the possibility that your network card/system board have gone bad. I mention this last because it's usually the hardest to test for a desktop. You'll have to take your computer somewhere with another, otherwise working internet connection and try it out. Sorry if any of this was too obvious.NByz (talk) 05:40, 16 March 2010 (UTC)

I was just taking a shower and thinking to myself: My feeling would be that if, when you did the release/renew, it took more than say... 5 seconds to return the error, I would lean towards calling your provider first, and the less time it took, the more suspicious I would be of your local hardware (especially your network card/system board).NByz (talk) 05:59, 16 March 2010 (UTC)

And of course, doublecheck your network settings in the control panel. Under TCP/IP properties, make sure everything looks normal in there. Everything should normally say "Obtain automatically."NByz (talk) 06:01, 16 March 2010 (UTC)

All routers I have come across use NAT by default, so the router allocating an IP address to connecting devices is not dependent on the router receiving an upstream IP address from the ISP. Even when unplugged from the phone/broadband you should be able to connect, receive an IP address, and view the router admin screens. I think I would do three things, firstly check out the router status from your laptop - looking at connected devices, etc. See if there is a limit on the range of addresses the router is set to allocate. Secondly I would check the LAN configuration on your windows box, make sure it isn't configured to ask for a fixed address. If neither of these work try borrowing another router or taking your PC to another network to see if it will connect to that. BTW, you have not given anything away about your network settings because you weren't even connected! -- Q Chris (talk) 09:38, 16 March 2010 (UTC)

best free fire-and-forget antivirus for Win 7 Home?

We just bought my computer illiterate mother-in-law an HP desktop with (legit) Windows 7 Home. What's the best free antivirus that I can install and set to regularly run/update itself on a regular schedule? In addition to the usual Admin / User account split, I want to make this desktop as bullet-proof as possible (for free) so that I don't have to be constantly going over there to do recoveries and such. I think most people with tech un-savvy parents can relate. I was thinking Spybot S&D would be a good start due to its realtime registry protection. Anything else? 61.189.63.188 (talk) 10:49, 12 March 2010 (UTC)

I've used AVG Anti-Virus Free Edition for quite a while, and it fits this purpose nicely. I set it up for my in-laws a few years ago and they have been happy with it, and more importantly I do not get calls about viruses. It's quite unobtrusive; the only issue I've found is that when a new version is released, it suggests you go ahead and buy the paid product (much like their website does) with small links to upgrade to the newer free version. This is fairly harmless. In my case, I told my in-laws that if it ever asked them to upgrade to a paid version, to look for the free version or to give me a call. (They actually ended up buying it anyways, but not because they forgot; my mother-in-law saw the notice, actually researched the difference between the paid and free versions, learned what the new features meant on her own and decided whether or not they justified the purchase. I was quite proud of her for this.) Coreycubed (talk) 15:10, 12 March 2010 (UTC)

I'd say Avast!. You have to get a code via email to use it, and then in 6 months or something it makes you get another one... I'm sure some people could accidentally convince themselves they need to buy the non-free version at that point. <shrug> If you want super free, you should check out ClamWin. ¦ Reisio (talk) 17:09, 12 March 2010 (UTC)

61, you are an excellent human being for doing the admin/non-admin split. 74.212.140.226 (talk) 17:32, 12 March 2010 (UTC)

I use Avira, and they have a free version. Nod32 gets consistently high ratings. ---— Gadget850 (Ed) ^talk 22:17, 12 March 2010 (UTC)

I recommend Microsoft Security Essentials (download link). Unlike AVG, it doesn't nag you to buy a paid version. You'll hardly notice it at all, actually. I also like NOD32, but it costs money. Indeterminate (talk) 10:26, 13 March 2010 (UTC)

Truecrypt error?

I get this message in my Ubuntu terminal when I use Truecrypt:

(truecrypt:8647): Gtk-WARNING **: /build/buildd/gtk+2.0-2.12.9/gtk/gtkwidget.c:8547:
widget class   `GtkPizza' has no property named `row-ending-details'

What does it mean?Quest09 (talk) 11:39, 12 March 2010 (UTC)

It's a bug in the software library that displays your buttons and things on the screen (called wxWidgets). It was fixed a couple of years ago so you may be able to get an updated version of the wxWidgets package that will fix it. I'm not sure of the effect of the bug, but it's discussed a bit here and here. Apparently changing themes might help. --Sean 13:41, 12 March 2010 (UTC)

Simple Python program

I have a very basic knowledge of Python and I am working in a simple program, mostly to myself and to learn the language.

I just want it to open a text, display it and if you double click a word, it should show the definition (from a dictionary) of the word in a separate window.

I know how to do things like opening, the dictionary with the definition and simple stuff. But how do you associate a double click on a word to an action?

Furthermore, can you have a Python window with drag-and-drop properties? Like you drag a file into it and the program opens it? --ProteanEd (talk) 17:30, 12 March 2010 (UTC)

All of these things are possible, but doing stuff with windows and clicking and drag-and-drop is probably not a very good learning exercise. I've been programming in Python for a while, and the thought of building a GUI program in it (or in any other language) is kind of terrifying. Things like Project Euler or 99 Prolog Problems (you don't need to know Prolog to solve them, though it might be hard to understand some of the examples) are more suited to training at programming. GUI programming (especially GUI programming that needs to interact with the outside environment, like drag-and-drop) tends to involve an awful lot of wading through manuals and tedious tweaking. I'd much rather try to find the best solution to "P09: Pack consecutive duplicates of list elements into sublists" than to figure out how to recognize a double-click event, and I'd learn more from the former, too. Or you could try to make your program a command-line program that gives the definition of a word that the user types in.

Even if you one day want to write GUI programs (a noble goal), I'd recommend getting the fundamentals down first. The reason that Python, and Scheme and other such languages are good for learning is that they don't give you a lot of extraneous trouble most of the time. In my (limited) experience, GUI programming is a lot of extraneous trouble.

That said, if your heart is set on this particular task, there's a list of GUI toolkits on the Python wiki. Good luck! Paul Stansifer 20:03, 12 March 2010 (UTC)

The simplest gui package for python is probably tkinter, which comes with it. Its main drawback is that the widgets are rather ugly and have their own style. It doesn't come with any docs, but the "Tkinter reference: a GUI for Python" document linked from tkinter is pretty good. 66.127.52.47 (talk) 08:50, 14 March 2010 (UTC)

Countering virus infection without antivirus program

Resolved

1. Does My Computer essentially mean your whole computer where ALL files are located? Which means, if I wanna do an extensive search through the whole computer (in my case, for virus), selecting "My Computer" as the location would mean my whole computer?

2. Another computer is infected by virus (NewFolder.exe), on 12 March 11:20PM GMT+8. I have already rebooted it to Safe Mode. If I am to conduct search with the following criteria:

• location: My Computer
• to include searching "hidden files and folders", "system folders" as well as "tape backup")
• Date created: from 12 March to 13 March (it's already 13 in my place)
• type of file: Application
• file size: at least 20,000KB (the virus size is 24,713KB or something around that number)

Is it safe to assume that the result will show ALL the virus files in my computer? Due to some reasons I don't have an updated antivirus program, and since the computer has plenty of important stuffs that aren't mine, I can't afford to reformat it.

Quick reply will be very much appreciated. Thanks in advance. — Yurei-eggtart 19:56, 12 March 2010 (UTC)

No, this is pointless. Viruses very often aren't individual files, but are instead changes done to several pre-existing files. You can't make assumptions about the sizes of files, because many viruses are polymorphic (they change with every infection, to evade detection). You can't assume they're applications, because many aren't. You can't trust the creation date, because that is trivial for a virus to forge. Viruses can lurk in places that a simple search like this can't find (the boot block, for example). Worse, some advanced viruses install a rootkit, which thwarts all but the most sophisticated attempts to detect them. You need an up to date anti-virus obtained from a trustworthy source; there is no substitute. -- Finlay McWalter • Talk 20:08, 12 March 2010 (UTC)

There are plenty of free anti-virus programs (e.g. Antivir, Avast!, AVG). Clarityfiend (talk) 20:18, 12 March 2010 (UTC)

I heard that there are many unreliable free antivirus programs, but I guess I'll try AVG out of desperation... But is it possible to download, install then execute it while being in Safe Mode? — Yurei-eggtart 20:27, 12 March 2010 (UTC)

Edit Looks like AVG has issues with other antivirus programs on the same computer? The infected computer has expired Norton antivirus program, am I supposed to uninstall it just in case (is it possible in Safe Mode?), in order to install AVG without problem? — Yurei-eggtart 20:50, 12 March 2010 (UTC)

You should never use more than one anti-virus software on a computer (and you should always have an updated anti-virus software). So uninstall the expired Norton, and then install AVG. --Andreas Rejbrand (talk) 20:56, 12 March 2010 (UTC)

More questions raining down... I don't see any Uninstall file for Norton. I've googled around and it says I should use Add/Remove program. There's the Norton Removal Tool, but I can't find the product key anywhere and updating it is impossible, what can I do if Add/Remove program doesn't completely work? And again, are all these possible via Safe mode? Thank you guys for the quick replies, really needed it (still needing it ._.). — Yurei-eggtart 21:14, 12 March 2010 (UTC)

They tell you to save your key so you can reinstall Norton again; if it's expired then there's nothing to worry about. If that doesn't totally remove it (after at least two reboots after running the uninstaller) then Revo Uninstaller is pretty thorough. -- Finlay McWalter • Talk 21:21, 12 March 2010 (UTC)

Oh God, I can't Add/Remove programs without going back to Normal mode. It's nearly impossible to operate with the virus lagging it. plus the fear of it corrupting any essential windows component. wwwhat am i supposed to do if AVG fails to help me? Reformat? Oh that's the worst thing I can do. Please enlighten me with ANY, ANY tip that may help in my situation. Oh my kudos to Wikipedian for swift replies... Uhh what will happen when the virus finishes duplicating folder-named .exe files? Time to corrupt the system files? As much as I don't want that to happen, I'd like to hear if theres such a possibiltiy — Yurei-eggtart 21:46, 12 March 2010 (UTC)

Edit: the uninstallation of Norton is still ongoing but Windows is warning me about low disk space, thanks to the virus duplication. What will happen when the disk space is completely full? Anything I can do to slow it down or whatever? Okay it has already reached its limit, now the uninstallation process hasn't been moving. Any method to improve the fast or something? — Yurei-eggtart 22:10, 12 March 2010 (UTC)

I start by pulling the drive and connecting it to a clan PC using a USB adapter. Scan it with Avira (AVG rates about the same), Superantispyware, Spybot – Search & Destroy and Malwarebytes' Anti-Malware. If I get a hit for Vundo / Virtumonde, then there are other tools. Pop it back in the system and it is usually workable to where you can install all those apps and scan again. You may need fixes for bits that can get disabled: MSInstaller, regedit, winsock and the like. If in doubt, call a prof ---— Gadget850 (Ed) ^talk 22:15, 12 March 2010 (UTC)

I guess Gadget850 means a "clean" PC and an USB disk enclosure. That's good advice - there comes the time when things are so broken that you can't really get it to run well enough to fix itself. Before you run those programs (I agree that they're all good) you should backup the data from the victim to the clean "medic" PC; with a system this badly mangled (and frankly I find uninstalling Norton often adds to the mangling) you can't discount the possibility that the files, or even the filesystem, are in jeopardy. -- Finlay McWalter • Talk 23:12, 12 March 2010 (UTC)

I have no idea what "USB adapter" or "USB disk enclosure" is so I don't know if there's one in my house. Will be it possible if I download, install and run Malwarebytes free version on the infected computer in Safe Mode with Networking, at the same time having expired Norton around? I have no knowledge of removing any component from the CPU so if my proposed method will work as fine, I'd love to do that instead.
Assuming I'll go with Gadget850's method, I'm kinda confused: cleaning up C drive essentially means cleaning up the whole infected computer? Well, there's only C drive in the computer; D is CD ROM one and E is.. unused. — Yurei-eggtart 09:52, 13 March 2010 (UTC)

CHEERS EVERYBODY, thank you for all the concern, my brother came to the rescue and got it done in 20minutes, no reformat required. He reckoned it was a weak virus. I got scolded, but not as bad as expected :'))) There's still rootkit left in the computer, but it should be okay from now on. Thanks again for all the help! — Yurei-eggtart 12:19, 13 March 2010 (UTC)

what is the name of the task manager executable on windows 7? (I'd like to start it with a shortcut)

Resolved

What is the name of the task manager executable on Windows 7? (like taskman.exe, taskmanager.exe, or something like it). I'd like to be able to start the task manager via a shortcut. Thanks.82.113.121.104 (talk) 23:24, 12 March 2010 (UTC)

taskmgr.exe (which I discovered using taskmanager) -- Finlay McWalter • Talk 23:31, 12 March 2010 (UTC)

thanks! that was it. I've added a resolved template... 82.113.121.104 (talk) 23:36, 12 March 2010 (UTC)

Why can't you simply use Ctrl+Shift+Esc? --Andreas Rejbrand (talk) 23:49, 12 March 2010 (UTC)

Not answering the question, but Process Explorer is much better —Preceding unsigned comment added by Fire2010 (talk • contribs) 20:28, 13 March 2010 (UTC)

March 13

Best inkjet printer for occasional use and refilling

I have a 5 year old Canon Pixma IP3000, which I used about once or twice per month. The current set of cartridges may be about 3 years old; I refilled them regularly. Now they are clogged, and deep cleaning doesn't help. I would have bought a new set of cartridges, but since I also begin to get paper jams, it's time to buy a new printer. I checked out Consumer Reports (to which I'm subscribed), but they only look for print quality, speed, and price per page. I don't care about price per page, and speed isn't much of an issue for me, either. Is there any review for what matters in my case, or does anyone have a recommendation? — Sebastian 01:41, 13 March 2010 (UTC)

Pretty much every printer I've ever had has had problems with paper jams, but feeding in paper one sheet at a time solves the problem, for me. Many have also had more serious problems, so I consider myself lucky when I get a printer that only jams. StuRat (talk) 01:57, 13 March 2010 (UTC)

Thanks, StuRat. Actually, the jamming is pretty bad now; I went to the local hardware repair service with it, but they said they couldn't fix it for the price for which you get a new one. I do want to avoid waste, and it goes against my grain to buy a new product instead of fixing the old one, but in this case it looks like I have to bite the bullet. Also, I do want to look out for a printer that takes better to the occasional use. The Pixma kept saying that it's low on ink just from sitting there, and I kept refilling it almost every time I used it, which freaked me out because I don't know where the ink went, if not on the paper. (The printer has a sponge that collects ink, but I'm not sure if that's where it went as it's hard to reach and not meant to be emptied or replaced.) — Sebastian 02:26, 13 March 2010 (UTC)

So feeding in one page at a time doesn't stop the jams ? As for the disappearing ink, I'd guess that the cartridge isn't properly sealed, leading to evaporation of the liquid component. The small solid component then probably dries on the sponge. Ink drying and clogging the ports is likely to be a problem with any ink-jet printer, so you may need to bite an even bigger bullet and buy a laser printer. While the purchase price is likely to be much higher, not having to continuously replace dried out ink and cartridges may make it cheaper in the long run. StuRat (talk) 13:31, 13 March 2010 (UTC)

No, unfortunately, it still jams. But thank you very much for your explanation; that seems indeed possible. At first, I thought it would be unlikely for the ink to evaporate through some minuscule leak (such as bad sealing of the fill hole), but it's possible that it evaporates from the sponge. Thanks also for the idea of the laser printer; if I used my printer more often, that would indeed be an interesting alternative. (There are some available at $350.) — Sebastian 02:34, 15 March 2010 (UTC)

As with most specialist questions of this sort, you may want to check out a more dedicated forum. In particular, I was looking in to refilling my catridges recently and found [2] was often recommended as a place to check out & seems to have useful information & quite a lot of people who have experience. [3] may be useful as well although I never really visited it.

FWIW, I found Canon printers were often recommended (except perhaps for CISS), although this may be influenced by the fact that I have a Canon printer and have a degree of bias towards them (liking their policy of individual ink catridges as well as avoiding chipped catridges for so long and even when they had them not generally completely preventing you from using unreset refilled catridges but simply warning and then recording in the EPPROM if you do followed by disabling monitoring). Canon also tend to have translucent catridges making manually monitoring the ink level and refilling easier and usually have removable print heads so you can try cleaning them if they clog which often works a few times I believe (buying new ones is possible but unlikely to be worth it).

Epson tend to have a reputation for worse clogging and similar problems particularly if you don't print often and are also know for their chipping practices (usually preventing you from printing if the catridges is refilled or expired) & generally strong stance against remanufacturers & third party catridges & chips including DMCA and patent infringement lawsuits. They do have a reputation for their photo quality particularly on special media which is probably the main reason they do receive a fair amount interest among refillers despite their problems.

HP don't seem to receive so much attention, although their printheads included with catriges would seem to be an advantage to those worried about clogs and for casual users. Not sure why but it may be because they've generally been closer to Epson in the way they've dealt with third party catridges and refills (e.g. chipped catridges refusing to work if refilled or expired, suing manufacturers although I don't think they've gone the patent route yet) and generally lack individual ink tanks and haven't had a reputation for quality so the only reason of interest is likely to be the print heads in catridges.

Never paid much attention to Lexmark but they don't seem to have been of much interest to refillers either, they're perhaps like HP but worse they don't even have their printheads built in to catridges.

In other words for my mostly uninformed opinion it'll probably come down to Canon or HP but I would recommend you research more first. I do know that if you do decide on Canon, the IP4500 which still uses the older CLi8/PGI5bk catridges would probably be better if you can find it then the newer IP4600 which uses the CLi521/PGi520 as the new catridges are smaller [4] and resetters and third party chips are newer and likely to be more expensive (and therefore the 3rd party catridges too) although this may not matter to you. It's still available here in NZ & of course is cheaper too although we tend to be behind & it isn't available at NewEgg (however perhaps retail stores will have it cheap).

Particularly since you appear to live in the US, you may also find it worthwhile checking out recommended suppliers of ink, some are better then others. Also methods of refilling.

Nil Einne (talk) 03:47, 14 March 2010 (UTC)

Thanks for your exhaustive tips! I'll have to check into the forums and good idea about checking ink suppliers. I wouldn't mind buying a Canon again; generally, I liked my old printer, and more friendly policies is something I want to reward. It didn't even occur to me that other printers might not have transparent cartridges - that's just so low! — Sebastian 02:34, 15 March 2010 (UTC)

Hex line numbers

How can I add hexadecimal line numbers to the beginning of each line in a text file? I know that nl can do this for decimal line numbers, but is there a way to use awk, sed, or some other command to do this? I'm hoping to take a text file like this:

First line
Second line
Third line
...
Ninth line
Tenth line

And turn it into something like this:

0x01 First line
0x02 Second line
0x03 Third line
...
0x09 Ninth line
0x0A Tenth line

or this:

01 First line
02 Second line
03 Third line
...
09 Ninth line
0A Tenth line

Daram.G (talk) 15:24, 13 March 2010 (UTC)

awk 'BEGIN { n = 1 } { printf("0x%X %s\n", n, $0); n++ }'. I don't know if there's a way to force the number of digits to be a multiple of two. --194.197.235.240 (talk) 16:19, 13 March 2010 (UTC)

Wow, that worked like a charm! Thanks a lot. Daram.G (talk) 18:45, 13 March 2010 (UTC)

Awk maintains a line count in the variable NR ("number of records"), so a simpler version of that program would be:

   awk '{ printf("0x%X %s\n", NR, $0) }'

--Anonymous, 05:16 UTC, March 15, 2010.

Using sed is harder but this "program" is derived from section 4.7 of the sed info examples:

sed -e 'x
/^$/ s/^.*$/1/
G
h
s/^ *\(.*\)\n/\1 /p
g
s/\n.*$//
/^F*$/ s/^/0/
s/.F*$/x&/
h
s/^.*x//
y/0123456789ABCDEF/123456789ABCDEF0/
x
s/x.*$//
G
s/\n//
h' file-name

One bug I have is the line number comes out twice. Graeme Bartlett (talk) 04:41, 14 March 2010 (UTC)

MediaWiki LocalSettings.php -- setting up Guest read-only account.

I'm setting up a wiki which requires being logged in to view any page except the login screen. In addition to the ordinary editor and admin accounts, I would like that there be an account called "Guest", that is allowed to view any page, incuding its source, but not to edit anything. How do I accomplish the last requirement? Here's what I've got so far:

# Prevent new user registration except by sysops.
$wgGroupPermissions['*']['createaccount'] = false;
# Require login to view anything
$wgGroupPermissions['*']['read'] = false;
$wgGroupPermissions['*']['edit'] = false;
$wgWhitelistRead = array("Special:Userlogin", "-", "MediaWiki:Monobook.css");

Thanks, --NorwegianBlue ^talk 15:29, 13 March 2010 (UTC)

Add this to LocalSettings.php (in addition to what you already have):

$wgGroupPermissions['user']['read'] = true;

$wgGroupPermissions['user']['edit'] = false;

$wgGroupPermissions['editor']['edit'] = true;

and then add all accounts you want to be able to edit to the "editor" group (the default WikiSysop account should have the rights to do that). You can create a Guest account and not add it to the editor group to get your desired functionality. You may also want to give some additional users the right to create accounts and make them editors - I think bureaucrats will be able to do that by default. mw:Manual:User rights management gives more information on this topic. --Tango (talk) 05:38, 14 March 2010 (UTC)

Thanks a lot! Worked perfectly. What I hadn't understood before reading your reply, was that I could add new groups in LocalSettings.php myself. --NorwegianBlue ^talk 11:48, 14 March 2010 (UTC)

Dell function keys

Resolved

My new Dell Studio's default behaviour is for e.g. F5 to increase the screen brightness and Fn + F5 to be the 'real' key, opposite to every other laptop I've used. This is very annoying. There was a thread on here recently talking about how to toggle this to the reverse, but I can't find it. How? Thanks 94.168.184.16 (talk) 20:20, 13 March 2010 (UTC)

Entering dell function into the little search box at the top of the page produces this: [5] --Phil Holmes (talk) 10:44, 14 March 2010 (UTC)

Ta. 94.168.184.16 (talk) 13:12, 14 March 2010 (UTC)

Single page PDFs > Online accessible format

My local archives did a massive project a few years back, scanning a dozen Tweedsmuir Histories. They're saved as individual PDFs, and each is high-resolution. (300 dpi, 18" x 24" or so, 100%.) Similarly, the local library system scanned a whole series of books by a 1930s historian. In both cases, the scans are somewhat useless, it's easier to just pull out the real book.

Is there any sort of website that these could be uploaded to, to be viewable in a format similar to Google Books? I've found various sites where people can publish magazines online, complete with the whole flippy page bit, but nothing free or cheap... they'd have to apply for a grant if it cost too much. -- Zanimum (talk) 21:40, 13 March 2010 (UTC)

Scribd; that article also links to some of Scribd's competitors. -- Finlay McWalter • Talk 21:48, 13 March 2010 (UTC)

You can also upload them to Google Books; it seems to need to sign up to be a Google Books partner. -- Finlay McWalter • Talk 21:53, 13 March 2010 (UTC)

Both options are only good if you have only one file to upload. Sadly, all 300 or so pages of each of the dozen books is a separate PDF. I can find a merge program easy, but the resultant file would crash a supercomputer. (I exaggerate, but it would be unwieldly.) -- Zanimum (talk) 22:09, 13 March 2010 (UTC)

I've merged some very large PDFs (full of scanned images) with PDFTK without issue. PDF readers are fairly smart (and one would assume those used by Scribd and Google Books are smart too) - they only load so much of a document into memory, so you can have a very large PDF without breaking things. -- Finlay McWalter • Talk 22:16, 13 March 2010 (UTC)

(Granted, I suppose I wouldn't actually need to open the merged PDF, if its only reason for being was to be uploaded.) -- Zanimum (talk) 22:11, 13 March 2010 (UTC)

Are they somewhat useless because the files take so long to load, and because they haven't been OCR'd? Because the simplest solution to that is to OCR them, and reduce or eliminate the photographic data itself (offer separately / upon request?). If they're not encumbered by copyright, etc., you could upload them to Wikisource or Project Gutenberg. I'd probably remove the photographs from the PDFs beforehand. ¦ Reisio (talk) 22:01, 13 March 2010 (UTC)

All of the OCR programs I've tried don't work. And as far as I know, I've tried all the free licensed ones mentioned on Wikipedia, plus more. Any recommendations? As for copyright, the 1930s books will be OK in a year or two, but the Tweedsmuir histories are a mess of orphaned works. -- Zanimum (talk) 22:09, 13 March 2010 (UTC)

I've uploaded old books to the Internet Archive. All you have to do is create an account and you'll be able to upload the pages in whatever format you want. Also, when you say the programs didn't work, do you mean that the OCR program interpreted the characters incorrectly? I've found ABBYY FineReader does better at mitigating that than other programs. Also, I've found that it helps to increase the resolution above 300 DPI when the characters are very small.--Chmod 777 (talk) 22:16, 13 March 2010 (UTC)

If it were me (and I've been in a similar situation with my own records), I'd first 1. try to find a way to download all the PDFs at once (maybe using a spider), 2. use PDFTK+ImageMagick to compress the individual PDFs into something reasonable (e.g. reduce the colors, to black and white if possible), 3. use PDFTK to combine the resultant files (takes forever, but won't crash a supercomputer, no—probably would take an hour or five on a modern computer), then, 4. maybe try an OCR program (whether it works depends on a lot of factors relating to the originals), 5. upload them to ScribD or something like that. --Mr.98 (talk) 22:21, 13 March 2010 (UTC)

Note that Scribd has an API which can do uploads; you should be able to find a library that talks the API for several popular programming languages (there's certainly a python one) which would automate the upload of your many files (heck, add an os.walk() call to the python example and you're mostly done). -- Finlay McWalter • Talk 22:26, 13 March 2010 (UTC)

And Google Docs has an API likewise - here -- Finlay McWalter • Talk 22:27, 13 March 2010 (UTC)

If these are solely black and white text, perhaps with some simple diagrams, consider converting them to 1 bit and compressing with JBIG2 or perhaps CCITT Group 4 compression if you want compatibility with PDF older then 1.4. The resulting PDFs shouldn't be too large especially since they're only 300 DPI. If they have colour, photos or complicated diagrams on some pages only, you can handle those seperately. Nil Einne (talk) 02:53, 14 March 2010 (UTC)

If they are of general public interest, please put them on the Internet Archive via here. They do all kinds of format conversions and OCR'ing automatically too. I can't stand scribd because you have to sign up for an account just to read stuff. 66.127.52.47 (talk) 08:52, 14 March 2010 (UTC)

I can't stand its UI, either... ¦ Reisio (talk) 08:57, 14 March 2010 (UTC)

March 14

latex multicols

I'm using the multicols package in latex but am having some difficulties with certain things. Firstly trying to get floats to sit inside the column, currently i have this:

\makeatletter
\newenvironment{tablehere}
  {\def\@captype{table}}
  {}
\newenvironment{figurehere}
  {\def\@captype{figure}}
  {}
\makeatother

In my preamble then i simply declare floats as \begin{figurehere}...\end{figurehere}, However this seems to make latex not consider the image and the caption as one entity, so at times i'll have the image on a separate page to the caption. Is there a better way?

Secondly, i have some wide tables that i want to put on a separate page, thats easy just do \begin{table}[p] but this makes the tables appear on a page at the back of the document, is there a way to put the page in the middle of the document, closer to where its being called?Thanks--82.26.227.101 (talk) 11:52, 14 March 2010 (UTC)

My monitor won’t work with a splitter cable

I have recently changed my monitor which had a VGA connector. My old monitor was a Viewsonic TFT. This was linked to my LCD television using a VGA splitter cable and worked perfectly, giving a display on both the monitor and the TV at the same time. My new monitor has a D.Sub connector. It is connected to my LCD TV exactly the same way and with the same splitter cable as my old monitor. Now though, when I connect the splitter to the TV my monitor’s display doesn't come on, the TV does. Unplug the TV and the monitor comes back on. Has anyone got a clue as to what is causing this. —Preceding unsigned comment added by Shsharri (talk • contribs) 12:35, 14 March 2010 (UTC)

There is no need to SHOUT. I have taken the liberty of converting your message to use lowercase where appropriate - it is now so much easier to read.

I think more information is needed. What kind of D.Sub connector does it have? - a white DVI connector perhaps? Take a look at List of video connectors and see if you can tell which it is. I'm also a little puzzled - you say the monitor is connected to your TV. Is that to view your PC on both TV and monitor screens, or to view TV pictures on both TV and monitor screens? Astronaut (talk) 13:07, 14 March 2010 (UTC)

Yea, we need you to fill in a chart like this:

                     OLD SETUP  NEW SETUP
                     =========  =========
Output from computer:   VGA        D-SUB
Input to TV:            VGA        VGA
Output from TV:         None       None
Input to monitor:       VGA        D-SUB
Output from monitor:    None       None

If this is correct, the confusing part is how a D-SUB signal is split into a D-SUB and VGA signal, under the new setup. StuRat (talk) 14:20, 14 March 2010 (UTC)

What brand and model is the new monitor? ---— Gadget850 (Ed) ^talk 14:43, 14 March 2010 (UTC)

I'm rather confused by the responses above and the question in general. The only D-subminiature connector commonly used in modern computer monitors AFAIK is the DE-15. This is also what people usually mean when they refer to a VGA connector. The DVI connector is not a D-sub connector, and I've never even heard it referred to as one. While I guess you could technically call it a VGA connector since you can send a VGA signal thorough it, again I've never heard it referred to as one. Ditto on both counts for the Displayport or HDMI. Nil Einne (talk) 14:18, 15 March 2010 (UTC)

Ditto— that is why I asked for the model so we could could find the documentation. I have given up on explaining connector nomenclature and just use pictures. ---— Gadget850 (Ed) ^talk 14:33, 15 March 2010 (UTC)

Many people use D-Sub to refer to all kinds of connector with a roughly D-shaped outer shield/ground (see File:DSubminiatures.svg for some examples), but I also considered it quite unlikely that they would have got a new, modern monitor with a really unusual connector. That is why I suggested perhaps a DVI and also suggested the OP take a look at our list. Astronaut (talk) 01:14, 16 March 2010 (UTC)

Handwritten Character database

I'm doing a software project (for college) that tries to recognize handwritten characters(English alphabet). So far I've been working with scanned handwriting samples provided by some friends. But for good training and testing 10,000's of characters might be necessary. I tried googling for such ready-made labelled databases. The only useful one I found was that of NIST and I can't spend (any) money to purchase it.

1. Is there a free handwritten character database out there?
2. Where can I find a list of good features that can help identify a character. Currently my features are not good enough (for characters like D and O etc.) —Preceding unsigned comment added by 59.93.2.126 (talk) 17:05, 14 March 2010 (UTC)

I'd distinguish between two types of writing:

1. Handwritten with ballpoint pen, as many people do now. That's probably the closest to your project, but I'm not sure if there is such a database available.
2. Calligraphy - written with brush. I would start with kaishu, and maybe progress to caoshu later. There should be many pages available online, but there's no mechanical way to assign the encoded character to the picture. — Sebastian 19:32, 14 March 2010 (UTC)

Please disregard my above post. I just realized that by "character", you did not mean Chinese characters. — Sebastian 02:36, 15 March 2010 (UTC)

This has some links (but not all are freely available), including this one, which looks promising. And see "zip code", the last entry on this page, which is apparently a classic database of digits from the USPS. You'll find digits and capital letters in the third dataset on this page, though there aren't too many examples. and it seems to have dirty data. Paul Stansifer 21:25, 14 March 2010 (UTC)

Thank you the links were helpful. 59.93.34.1 (talk) 01:08, 16 March 2010 (UTC)

"Gothic" fonts

Why are fonts such as Bank Gothic called "Gothic"? ╟─TreasuryTag►Chancellor of the Duchy of Lancaster─╢ 17:09, 14 March 2010 (UTC)

From our Sans-serif article: "Before the term “sans-serif” became standard in English typography, a number of other terms had been used. One of these outmoded terms for sans serif was gothic, which is still used in East Asian typography and sometimes seen in font names like Century Gothic." Comet Tuttle (talk) 17:49, 14 March 2010 (UTC)

East Asian sans-serif typeface says "Gothic is an outmoded typographic term for sans-serif. It was so named because the type color of early sans serif typefaces were thought to be similar to that of the blackletter or 'gothic' script."; however there is no reference to support that claim. --Normansmithy (talk) 11:30, 15 March 2010 (UTC)

Rotten Tomatoes webpage problem

When I click on the appropriate buttons here http://www.rottentomatoes.com/features/special/2007/botbp/ I just get taken to the same webpage again. What is wrong please? I am using Firefox, all "cookies" enabled. The same thing happens when I use Internet Explorer 8. Is there anyone for whom the webpage does not do this? Is it some sort of pop-up which my browsers are banning? Perhaps it is being banned for malware reasons. Thanks 89.242.120.116 (talk) 18:52, 14 March 2010 (UTC)

That thing is from 2007, and has a stated cutoff date. ¦ Reisio (talk) 05:59, 15 March 2010 (UTC)

The smallprint says the cutoff data for gathering the statistics was in February 2008, it does not say anything about the webpage being unusable after that or any other date. So it still a mystery. Very bad web design by RT to have glossy duff webpages that do not do what they say they will. I have found the current URL and will update the RT wikipedia article link, which is where I got it from. 89.242.243.82 (talk) 11:47, 15 March 2010 (UTC)

Banned torrent

I was downloading a torrent from a private torrent tracker and it got banned by the tracker. Apparently the uploader forgot to make the torrent private so it's still being seeded over DHT and Peer exchange. Will they stop working when I have to update my tracker or will they continue to work forever? Thank you 93.136.219.166 (talk) 20:16, 14 March 2010 (UTC)

I am not quite sure but, They will peter out, but updating the tracker will not affect things. The tracker is a way for different peers to find each other, so without the tracker it is difficult for new peers to join the swarm Taemyr (talk) 11:38, 15 March 2010 (UTC)

Photoshop problem

Why is it that sometimes, in Photoshop, no matter what I do or if I restart the program, or create a new layer, or switch layers, or whatever, it only lets me draw a straight line? How do I fix it? Thanks, Shannon^talk _contribs 22:19, 14 March 2010 (UTC)

With what tool(s)? Some really basic things: Try tapping the "Shift" and "Control" keys a few times—it might just think they are being pressed (and that can restrict its line-drawing functions). Last if not least, try rebooting the machine, see if it persists. --Mr.98 (talk) 00:16, 15 March 2010 (UTC)

Which files are the most difficult to compress?

This question has frequently arisen in my mind. In file compression, it is obvious that the files that are the easiest to compress (i.e. shrink the most when compressed) are those which consist entirely of the same byte value, perhaps even entirely of 0-bits or entirely of 1-bits. But which files are the most difficult to compress (i.e. shrink the least when compressed)? This obviously depends on the compression algorithm, but has there been any definite research results about this on any popular compression algorithm? This question might sound like the answer cannot be known, but upon further thought, the problem is often indeed solvable. If we assume a given file size (such as an n-pixel digital photograph), there are a finite number of possible files, so there must exist a specific solution (if not necessarily a unique one). It's just a matter of finding out what that is. Unfortunately, for pretty much all non-trivial cases, the number of possible files is so huge that a brute-force approach to solving the problem would not complete until the Sun goes supernova. So finding the solution requires a more clever approach. Has any been tried? JIP | Talk 22:35, 14 March 2010 (UTC)

Generally, files that compress have predictable patterns of bytes (not just all the same). Files that compress poorly have a random byte structure. --Phil Holmes (talk) 22:46, 14 March 2010 (UTC)

That's right — a file with randomly generated content is not going to be compressible. (I mean, there might be a little, like if your file randomly contains the letters "AAAAAAAAAAAAAAAAAA" at one point; but that's unlikely indeed.) See data compression, which is a surprisingly small article but has many links to related interesting articles. Comet Tuttle (talk) 22:55, 14 March 2010 (UTC)

It was a much larger article, before it was compressed. :-) StuRat (talk) 02:53, 15 March 2010 (UTC)

Though, just to be pedantic, and useless to the spirit of the question: depending on the nature of the random data, there might be simple ways to "compress" it. If your random data is the first billion digits of pi, it would be easier to just write a short program that generated the data, than it would to compress the data itself. This is related to Kolmogorov complexity—technically you want data that is not only random, but complex, or something along those line (I am not a mathematician... or a computer scientist!). Or put another way, it depends on our definition of "random". But has nothing to do with real-world file compression as far as I know. And should thus be ignored by the poster unless they are just curious! --Mr.98 (talk) 00:39, 15 March 2010 (UTC)

Let me introduce you to the work of a chap named Claude E. Shannon on entropy (information theory). Marnanel (talk) 23:27, 14 March 2010 (UTC)

Besides "stuff that was chaotic to start with" and "stuff that's already been compressed", another class of files that are hard to compress is encrypted files. If an encrypted file contains any patterns that a compressor can take advantage of, those patterns may also be useful to an attacker trying to break the encryption. This is why whenever encryption and compression are used together, the compression must be done first. 98.226.122.10 (talk) 01:44, 15 March 2010 (UTC)

The main problem with the question is that it is ill-posed. You've made an incorrect assumption to start with, which will affect the entire approach you take. As per sun#Life cycle, the sun will NOT go supernova but will instead evolve into a red giant star, following the main-sequence. You may want to read up on stellar evolution and formation and evolution of the Solar System and come back if you have any further questions. By waiting for the sun to go supernova you actually afford yourself an infinite amount of time, thus a brute force method would be guaranteed to work. Zunaid 12:15, 15 March 2010 (UTC)

Your observation is completely correct, but as it depends only on the assumption that the Sun will go supernova instead of becoming a red giant, which is a matter of astronomy and not mathematics or computing, I am fairly sure you are being overly pedantic here for the purpose of amusement. =) JIP | Talk 17:44, 15 March 2010 (UTC)

Intro to Computer Science

I'm trying to learn more about computer science and possibly work on some projects. I have a decent grasp of Java but I don't know where to go from here. Should I just keep working in them? So far I've just been doing the Java tutorials and experimenting with some of the articles they have. Any recommendations about what I should do? Much appreciated. 66.133.196.152 (talk) 23:36, 14 March 2010 (UTC)

If you've self-taught yourself to have a decent grasp of Java, congratulations. Take on more ambitious and bigger projects that will force you to learn more about particular areas that you aren't comfortable with yet: Networking, graphics, user interface, performance optimization.... There are plenty of software engineers in the first rank of their profession who are self-taught. Comet Tuttle (talk) 04:54, 15 March 2010 (UTC)

Studying computers is like studying medicine. You can become an eye doctor, a cardiologist, a plastic surgeon, etc. Likewise, you can work as a network technician, a programmer, a computer repairman, etc. That's why I don't like the phrase "computer science" very much. It's too vague. At a university, if you major in computer science, you end up learning mostly programming. But there's so much more to computers than writing programs. Many people earn one or more certifications in networking, security, web design, server administration, hardware repair, Windows, Linux, Mac OS X, etc. You could specialize in any one of those fields (among others) and have more than enough to learn. I'd recommend learning a little bit of everything. Whatever you find interesting, you should specialize in.--Chmod 777 (talk) 05:10, 15 March 2010 (UTC)

Some quotable guy once said: Computer science is no more about computers than astronomy is about telescopes. 98.226.122.10 (talk) 06:25, 15 March 2010 (UTC)

It's a good idea to see some kind of project through to completion, because finishing something and making it work is surprisingly tough. But you might want to choose your next project to try out a field of CS that interests you. Here are some fields that haven't been mentioned:

• programming languages - learn a functional language (actually, every programmer should know a few radically different languages)
• algorithms - write something that needs to access a huge amount of data in an interesting way, and make it perform well
• machine learning - there are lots of data sets available for free, like the netflix prize dataset. Try to analyze something about them. Or for some quick fun, implement dissociated press.
• theory of computation

Good luck! Paul Stansifer 13:14, 15 March 2010 (UTC)

• Try solving some Project Euler problems if you want to program some mathematically-oriented exercises. If you want to get started in functional programming, I like http://learnyouahaskell.com . If you want to contribute to Wikipedia's back-end software (it's collaboratively written, just like the encyclopedia), visit http://bugzilla.wikimedia.org and find some items you think you can help with, and join in. Note it is mostly written in PHP, a pretty easy language, but there are some parts in Java if you prefer that. For computer science, hmm, try CLRS. For a bit more academic approach to programming, try SICP or CTMCP. 66.127.52.47 (talk) 10:40, 16 March 2010 (UTC)

Recommendations for a wireless router

I have a Linksys WRT54G router which has for the most part been good to me, but I am looking for a better one. I'd like one with great range and speed, a connection that doesn't drop/need to be restarted, and preferably dual band. I looked up reviews for routers, and one that stands out is the Netgear WNDR3700. Anyone else have suggestions? I'm not averse to spending a lot of money if it means I get a quality router that lasts me long time, so expensive suggestions are welcome. 24.189.90.68 (talk) 23:50, 14 March 2010 (UTC)

Have you tried swapping out the firmware for something like Tomato (firmware) or one of the other HyperWRT firmwares? It's apparently compatible with your router and I have heard that it helps improve stability and similar. Gunrun (talk) 09:11, 15 March 2010 (UTC)

Neither are compatible with mine, since it's v.8. 24.189.90.68 (talk) 10:03, 15 March 2010 (UTC)

+1 for Tomato. Stable, nice interface, lots of options (if you need them). I'm running it on my WRT54GL. 121.72.169.25 (talk) 10:06, 15 March 2010 (UTC)

Consider VPN capability. - Kittybrewster ☎ 10:15, 15 March 2010 (UTC)

March 15

Cannot access admin account

Resolved

Sorry for the double-posting, but this problem most certainly wasn't planned. I cannot access my administrator account on Windows XP. It has no password, but whenever I try to log on, all I get is "Loading personal settings..." and it stays that way forever. I have a backup admin account, but I was dumb enough to put a password on it, and even dumber to not remember where I put the password that I wrote down. So now I cannot log on to Windows as an admin, only my limited account (which I am typing this from) is still accessible. I don't have an OS installation disk, so reinstalling Windows is not a possibility for me. What are my options?24.189.90.68 (talk) 05:40, 15 March 2010 (UTC)

There are so many ways to get administrator access on XP, it's not even funny. :p http://www.google.com/search?q=%22windows%20xp%22%20forgot%20admin%20password ¦ Reisio (talk) 06:01, 15 March 2010 (UTC)

Obviously, the OP has no trouble getting access (if he did, then he would not be able to see "loading personal settings..."). His user just has trouble loading profile for some reason. --164.67.235.148 (talk) 05:20, 16 March 2010 (UTC)

No worries, Ctrl+Alt+Delete saved me, thanks! 24.189.90.68 (talk) 10:00, 15 March 2010 (UTC)

New SSD: clone or reinstall?

I am currently using a normal hard drive. If I buy a new SSD, can I just clone the hard drive to the SSD or do I have to reinstall the OS? 121.72.169.25 (talk) 10:25, 15 March 2010 (UTC)

It depends on your OS. If you have to install drivers to use the SSD in windows (i'm assuming you use windows) then it's not likely to work because, while windows would boot from the SSD, once windows started it wouldn't know how to work the SSD and you'd get a BSOD. Although, you could install the driver beforehand...but I'm not sure that would work... Even if it did, you'd be required to reactivate your windows installation because it detected a hardware change. On linux, it wouldn't be an issue.  Buffered Input Output 14:51, 15 March 2010 (UTC)

I am using Windows 7. 121.72.217.246 (talk) 19:15, 15 March 2010 (UTC)

It's probably easiest to reinstall, then copy your user files over (possibly using Windows Easy Transfer). You could try to clone your current hard drive, but in my experience that doesn't usually work well with drives that are different sizes. Indeterminate (talk) 10:05, 16 March 2010 (UTC)

SSD/Moore's Law

Does Moore's Law applies to SSDs? Should I expect SSDs halve in price or double in capacity next year? 121.72.169.25 (talk) 10:25, 15 March 2010 (UTC)

Moore's law applies to memory and many other components of computer systems, as well as to processors. Of course, it's just an approximation. But solid-state drive price/performance largely depends on that of flash memory; flash memory storage rates seem to be increasing a little faster than Moore's law[6][7]. --Normansmithy (talk) 13:31, 15 March 2010 (UTC)

Moore's Law is based on the idea that transistor density doubles every 18 months or so. It's an approximation, as of course companies and people within them have control over how quickly this actually happens. The cost of an SSD drive should half 18 - 24 months due to the ability to cram twice as many transistors on to the same amount of resource (wafer).

Don't confuse capacity with density. Capacity can be changed just by adding more drives or flash chips. The idea of Moore's law is that we can double the amount of transistors that we can get in the same physical area, not that we can make faster processors (or larger storage) by using more transistors. —Preceding unsigned comment added by 194.200.65.239 (talk) 14:06, 15 March 2010 (UTC)

Also note that price isn't necessary going to be cut in half just because density doubles. You may be able to buy a 2 TB drive for the cost of a 1 TB drive 18 months ago, but that doesn't mean a 1 TB drive will cost half as much as it did then. This is because prices aren't necessarily proportional to capacity, which is quite obvious with USB flash/pen drives, where the lowest cost per GB is somewhere around the 16-32 GB range, with prices per GB going up both for smaller and larger sizes. StuRat (talk) 16:44, 15 March 2010 (UTC)

You should also be aware that the price collapse of flash memory (exceeding Moore's Law?) over the last few years is not likely to continue, in fact it might soon slow considerably.Future pricing. Dbfirs 10:49, 16 March 2010 (UTC)

to connect two wifi devices

How to connect two wi fi devices, one compoter and other a robot so that afrer connecting the two the robot could be run using the computer? —Preceding unsigned comment added by Aishranj (talk • contribs) 11:37, 15 March 2010 (UTC)

Can you elaborate any more?  Buffered Input Output 14:52, 15 March 2010 (UTC)

The PC may be able to function as a wireless access point. Otherwise, you will need a third device such as a wireless router. Once both devices have an IP address, you can write a program or find pre-made software that uses socket programming to send data in both directions. Finally, you will need to design or find a program which can understand the data that you send and interpret it as commands. Typically, this will require a lot of programming effort on your part, unless you have a pre-made kit or commercial toy robot. Nimur (talk) 15:48, 15 March 2010 (UTC)

I've never used it but ad hoc mode is supposed to allow two devices to communicate without a router. -- Q Chris (talk) 15:58, 15 March 2010 (UTC)

It is very possible that a "robot" (rather, an embedded computer with an 802.11 radio) has limited or no support for ad-hoc networking. But, if you have the budget, you can get a full-blown, totally standards-compliant 802.11 radio system on an embedded mainboard; and nowadays, netbook-like devices are so small and cheap that you can quite probably mount one on your robot locomotion platform. Here is a nice project report called An Open Robot Platform for Mobile Ad-Hoc Network Research from the Wireless Group at University of Texas at Austin. Its an "undergraduate-level" project report and should be fairly readable if you have any engineering inclination. Conveniently, there are references to specific hardware platforms, total system cost appears to be about $1500, (which is "dirt cheap" by wireless robot standards). The main board is a NR10000EG embedded x86 system. Nimur (talk) 18:01, 15 March 2010 (UTC)

A Lego Mindstorms NXT system ($261 new) will connect wirelessly to a PC using Bluetooth. The range is a little more limited than WiFi - but it's cheap, super-flexible and literally anyone can learn to program the thing using Lego's graphical programming system. SteveBaker (talk) 03:00, 16 March 2010 (UTC)

Some wifi network cards can operate in infrastructure mode (act as access point). In windows, this functionality usually is available in software, which came with card, in linux, there is iwconfig option (mode master, if i remember corectly), bu i have not seen a device supporting this. -Yyy (talk) 08:11, 16 March 2010 (UTC)

Promissory abstracts

I am currently in the process of submitting an abstract to a conference for a computer science project I worked on during last summer. The conference site says, "Promissory abstracts are discouraged." What are "promissory abstracts"?

70.29.24.251 (talk) 14:55, 15 March 2010 (UTC)

It appears to be an abstract for something you have not yet written or implemented, see this link. -- Q Chris (talk) 15:15, 15 March 2010 (UTC)

Want to keep text between two text strings and discard everything else

I have over a hundred text files in a folder. They are all identical except for a small amount of text part-way through them. This text can be identified by text-strings before it and after it. Is there any easy to use (ie has a GUI) free software that would do this please? Or failing that, something without a GUI. I'm using Windows XP. Thanks 89.242.243.82 (talk) 15:57, 15 March 2010 (UTC)

About how many text strings are there total ? If there's only a few, it might be easier to edit the files manually and to do a find (Control F) than to write a script to do it. StuRat (talk) 16:28, 15 March 2010 (UTC)

For over a hundred text files, that is probably not the easiest way. I am sure that some clever shell scripter can do this in about one line of perl. --Mr.98 (talk) 16:42, 15 March 2010 (UTC)

If the files are exactly identical, you don't even need a string match - you can just count the size of the header and footer, and trim that many bytes off of the start and end of every file. This could be done easily in most scripting languages - without resorting to regular expression processing - do you have a script-language preference? Nimur (talk) 18:08, 15 March 2010 (UTC)

grep --194.197.235.240 (talk) 18:44, 15 March 2010 (UTC)

grep isn't a great choice if you're trying to extract a multiple-line block of text. awk or perl would be easier. -- Coneslayer (talk) 18:56, 15 March 2010 (UTC)

Sorry, bad answer from me. (but let's not forget -A) 194.197.235.240 (talk) 22:00, 15 March 2010 (UTC)

Assuming that the file names are of the form [First-uninteresting-variable-part][First-identifier][Interesting-part][Second-identifier][second-uninteresting-variable-part], and you want to isolate [Interesting-part] only:

First do

dir /b > wrk_1.txt

Then open wrk_1.txt in notpad, and replace [First-identifier] with a character (such as "|"), that does not occur in the filenames. Likewise with [second-identifier]. Save as wrk_2.txt. Then open wrk_2.txt in excel (menu option "Data|Import text file", or something similar; I'm translating from Norwegian here). Select "Data with separators", and select the "|" character as the separator. When the data has been imported into excel, your interesting data is in column B, and can easily be copied back into, say notepad or whatever. --NorwegianBlue ^talk 19:07, 15 March 2010 (UTC)

There is a large amount of text to discard - its about 360kb worth per file, so I fear that method would overload things and not work. I have three different folders of material and the biggest is two or three hundred files.

The format of each file is something like this: (Lots of stuff I want to discard - same or nearly the same in every file), (A few lines I want to keep, length varies from file to file), (Lots of stuff I want to discard - same or nearly the same in every file). 89.242.243.82 (talk) 20:55, 15 March 2010 (UTC)

there's a big difference between 'same' and 'nearly the same' here. any way you look at it, you need to specify for the computer precisely how to slice the documents, which means you need to find something exactly and completely consistent across all the documents that marks the cut points. If you had to explain to me (in words) where precisely I would cut this document if I were doing it by hand, what would you say?

sorry... if this were a Mac I could tell you how to do this in about twelve seconds - TextWrangler is an ideal tool for tasks like this, but it's Mac-only. call me a maid if you must, but either way I don't do Windows. --Ludwigs2 22:17, 15 March 2010 (UTC)

The lines of text I'm interested in can always be identified by some text before and (different) text after. So ideally I'd like to be able to tell something to save everything between the text strings "abcde" and "uvxyz" and discard the rest. Another possibility would be to do it in more than one pass: 1) chop off and discard everything in the file up to and including the text string "abcde". 2) chop off and discard everything after and including the text string "uvwxyz". I have been looking for freeware that can do this - have not found anything yet. Thanks 89.242.243.82 (talk) 22:31, 15 March 2010 (UTC)

My previous suggestion was based on the assumption that is was the file names that were of interest, but if it is the contents; in each directory do:

grep [First-identifier] *.* > wrk_1.txt

and (if necessary)

grep [Second-identifier] wrk_1.txt > wrk_2.txt

Then proceed as I suggested above (you may need to sort wrk_2.txt first, and remove by hand some header lines that grep produces). --NorwegianBlue ^talk 23:00, 15 March 2010 (UTC)

Wouldnt this just create one huge file called wrk_1.txt? Then the second command would not work. Looking at the grep article suggests that this will only work for individual lines, but the files are very large documents and have many different lines. 92.24.26.120 (talk) 23:45, 15 March 2010 (UTC)

I would pass it to a database to store it using a SQL query. It would be much faster. You could put this in your ASPX file:

SqlConnection connection;

SqlCommand command;
connection = new SqlConnection("Data Source=your data source, etc.");
command.CommandText = "INSERT, etc.";
connection.Open();
command.ExecuteNonQuery();

connection.Close();

You first have to parse the files using a simple regex script. Then, you can retrieve any queries you want from the DBMS. Install the DBMS on your local machine. I would recommend indexing the DB (CREATE INDEX, etc.), too, to speed up lookups. Is the data already in 3NF?--Chmod 777 (talk) 00:34, 16 March 2010 (UTC)

As it says at the start, they are just large text files. 92.24.26.120 (talk) 01:46, 16 March 2010 (UTC)

Exactly, so you should store the text in a database to speed up queries. I don't understand why you wouldn't do that.--Chmod 777 (talk) 02:45, 16 March 2010 (UTC)

I think we must be on different planets. 92.29.19.22 (talk) 10:01, 16 March 2010 (UTC)

I have found some freeware which may be able to do what I want: Text Magician, Piececopy, PowerUtils1.9, and DJuggler. Its a pity that there is no version of grep etc that can work with paragraphs, not just lines. 92.24.26.120 (talk) 01:46, 16 March 2010 (UTC)

If those don't work, perl will. Pipe each file through perl -ne 'next if (1 .. /REGEX_THAT_MATCHES_PRECEDING_LINE/); last if (/REGEX_THAT_MATCHES_FOLLOWING_LINE/ .. 1); print;' —Korath (Talk) 10:32, 16 March 2010 (UTC)

Computer froze like it never froze before

I don't know if I did something wrong on the keyboard, but here's what happened.

I was using inbox.com email, which has one specific purpose for me.

I wasn't getting a satisfactory repsonse to a question I asked them about copy and paste when the email is not plain text, so I tried again. While I was doing that, I typed "the" in the place for the URL and ended up with a list of possible sites to go to just below the line for the URL. I couldn't finish typing the address. Also, the cursor just disappeared, except it was a rotating circle in the area where the possible choices of URLs were.

Not knowing what else to do, I turned off the computer. This took a while. My computer (described here if you scroll down below the description of a similar problem) shuts down before actually turning off. When I turned it back on (after the Windows update and the "configuring updates message" that surprised me since I had asked to postpone the automatic shutdown), I was given two choices because Windows had shut down unexpectedly. I chose to open the tabs from before--this included a help screen and a feedback screen where I had informed inbox.com they were not helpful at all, and I was using the box as a notepad to copy from the URL that started with "the" so as to avoid the problems when it's not plain text.

The screen that came up with the original email asked me to sign in. When I did the screen just went blank and I had the rotating cursor again. I don't even think I was able to go to the other two screens. I had to turn the computer off, and when I turned it on again, I chose not to reopen tabs, but started over instead. All was well.Vchimpanzee · talk · contributions · 22:01, 15 March 2010 (UTC)

Sounds like an eventful half-hour. I think what you're saying is that after a reboot, you restarted your web browser, which offered you the choice of opening the tabs that were open when it was forcibly shut down. You took this choice, but the page you followed did not work. That's most likely because your session with inbox.com had timed out (and/or your IP address had changed), and inbox.com did not deal gracefully with the unexpected event of your browser's new request for service. Meanwhile windows had done all of an update bar the reboot; it took advantage of the reboot which you did by turning the machine off. In short, just a bad hair day. --Tagishsimon (talk) 00:03, 16 March 2010 (UTC)

mp3 quality

Is 98kb/s an acceptable quality level for most music? —Preceding unsigned comment added by 76.123.154.78 (talk) 23:09, 15 March 2010 (UTC)

"acceptable" really varies depending on who's doing the listening as well as what the music is. Personally I find 128 kbs is just fine for everything, but anything lower (like 112 kbs) sounds a bit flat and even lower still (like 96 kbs or lower) just sounds tinny, but that's just me. ZX81 ^talk 23:41, 15 March 2010 (UTC)

It depends on how good your speakers are, whether the audio is mono or stereo, whether the audio has been compressed, and whether that b in the kb/s means bytes or bits. Music off of a CD is 88 kilo-bytes (705 kilo-bits) per second when converted to mono, but twice that straight off the CD in stereo. Converting to mono divides the bit rate by two. With light MP3 compression, you can get CD-quality audio in about a half of that rate (320 kilo-bits per second). FM radio is about 256 kbps as an MP3, and AM radio is about 64 kbps as an MP3.--Chmod 777 (talk) 00:02, 16 March 2010 (UTC)

I think most people would find 98 kbps a bit low. --Mr.98 (talk) 02:17, 16 March 2010 (UTC)

I usually rip at 192 kbps. IMHO, it gives a nice compromise between filesize and acceptable quality through the speakers/headphones I use with my PC. 96 kbps is nowhere near as good, but the resulting files are small enough to allow me to fit several albums on my cell phone (useful when commuting and the background noise is high anyway). I don't know where Chmod gets his radio from, but in my experience FM radio sounds like 128 kbps and AM radio like 64 kbps or less. Astronaut (talk) 04:50, 16 March 2010 (UTC)

Most people with good hearing can hear sounds up to about 20 to 22kHz. The Nyquist sampling theorem says you need twice that for good reproduction - and you have two ears - so you need twice that. That gets you up to 88kHz. You need at least 8 bits per sample - so 700 kbits/sec is really the minimum for high quality audio. Some people will argue that you need 12 bits per sample 'linear' coding rather than 8 bits companded - so arguably, a megabit per second is "perfection". Mpeg compression does a good job of reducing that drastically - but any lossy compression scheme loses some quality. So even at 128 kbits/sec you're losing some quality. But a lot depends on how good your hearing is. If you're young - you'll certainly notice the difference at 98kbits/sec - you're older or if you wrecked your hearing by listening to music too loud or something - then you may well find 98 kbits/sec perfectly OK. SteveBaker (talk) 02:48, 16 March 2010 (UTC)

Sound problem

In the last few hours my Windows 7 computer has begun having problems with sound playback. The problem is that when I play a music file for example it plays fine until I start to do anything else like browse the net or open a folder or basically anything which uses some cpu then the sound becomes all distorted and skippy while I do stuff, but if I leave the computer complexly alone except for music it works fine. As I said, this problem only started in the last hour or so. Any ideas what's causing it, and how to fix? —Preceding unsigned comment added by 76.123.154.78 (talk) 23:09, 15 March 2010 (UTC)

If my experience with windows media player on vista on a small dell laptop is anything to go by, it is as simple as WMP is crap and unable to cope without, I don;t know what ... much more memory ot more processor, or, frankly, someone more competent to code it in the first place. Simplest advice: get a new music player such as winamp or VLC media player. Clearly, if you are not using WMP, then all bets are off. Mine stutters as it reaches the end of any track, presumably as it starts to read the next track. So a 5 second burst in the last 20 seconds of any track is unlistenable. Great job, Bill. --Tagishsimon (talk) 00:15, 16 March 2010 (UTC)

And, if you haven't tried rebooting, try that now. I bet it fixes the problem. StuRat (talk) 00:42, 16 March 2010 (UTC)

Windows Media Player has always worked fine under Windows Vista on my Dell laptop. It certainly seems like something has swallowed all the available processor/memory resources. If a reboot doesn't fix it, look for malware or virus activity. If the problem is with streaming music straight off the internet, you might like to check your intrnet connection. Astronaut (talk) 04:36, 16 March 2010 (UTC)

I'm not using Windows Media Player, this problem is affecting VLC, mplayer, and even windows own sounds like the start up "ta-da" sound. I've rebooted many times and it hasn't fixed it

Open office draw fit text to curve

Is it possible to fit text to a bezier curve using open office draw - eg such as having "M1 motorway" on the edge of a 45degree turn.. (like on maps)

Is inkscape good at doing this? Or maybe something else?87.102.67.84 (talk) 04:24, 16 March 2010 (UTC)

I don't know about openoffice, but inkscape can definitely do this, see [8].131.111.185.69 (talk) 04:59, 16 March 2010 (UTC)

Thanks.87.102.67.84 (talk) 11:03, 16 March 2010 (UTC)

business

what is the relation between MRP,ROT%,RATE,E.D,D%,AMOUNT AND HOW THEY ARE CALCULATED?Supriyochowdhury (talk) 05:29, 16 March 2010 (UTC)

Are any of the MS Windows 22 BrowserChoice options written in pure Java?

The BrowserChoice screen was designed in accordance with a competition law decision issued by the European Commission in December 2009.
These days it is shown to all Microsoft Windows users,in Europe, who currently have Internet Explorer as their default browser.
Q: Are any of those 22 suggested web-browsers written in pure (no native code) Java?
--Seren-dipper (talk) 06:25, 16 March 2010 (UTC)

No. If you look at Template:Web browsers, under Java-based browsers, it looks like Lobo, Teashark, and X-Smiles are the only current browsers that *might* be entirely written in Java, and they are not on the BrowserChoice.eu list. The vast majority of browsers are written in C++. Indeterminate (talk) 09:56, 16 March 2010 (UTC)

anonymous

Can anyone recommend a free download for a Mac to keep my IP address anonymous please. Thanks in anticipation.--Artjo (talk) 07:17, 16 March 2010 (UTC)

Well, there's no perfect solution. Tor (anonymity network) is probably your best choice for anonymity, but it can be a bit slow. Free web proxies are much easier to setup and use, and there's usually nothing to download. Indeterminate (talk) 09:32, 16 March 2010 (UTC)

Software for synchronising separately recorded sound to HD video?

I recorded three great new bands in Brighton on my HD camcorder, but Radio Reverb had loads of professional microphones and direct lines to the instruments leading to a mixing/CD recording desk, which would presumably exceed even the Dolby 5.1 internal microphones on my camera (which seem to give studio quality sound) and I agreed with them to share the media in the hope of synchronising the audio (presumably to arrive ready mixed on a CD) to my video and then on to blu-ray disk. What software can I purchase, preferably at a reasonable price, to do thus? My computer is a modern dual Pentium dual core 2.4 ghz machine with a reasonable hard drive capacity, which I might upgrade to 2 terabytes. I am running windows XP and would prefer not to upgrade to Vista in case it breaks certain applications I have written in visual basic. My existing Sony software plays the HD video quite well, though the motion is smoother on a proper HD set and blu ray player, or (when down-converted for DVD) a standard DVD and wide-screen cathode ray set, which I do not want to get rid of due to better colour contrast than flat screen HD televisions. Would it be cheaper to get this done by audio-visual professionals instead? filming (great) bands (with their permission) is my hobby and they use their copies as a free promotional tool, I do it to get the footage. —Preceding unsigned comment added by 80.1.80.16 (talk) 13:29, 15 March 2010 (UTC)