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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)

And our Sun going red giant will kill us just as surely as a supernova would, provided we stay on Earth. Unless we develop some really good A/C... :-) StuRat (talk) 12:48, 16 March 2010 (UTC)

Yes yes of course that too, but I thought I'd leave that part out...I was also going to link "infinite amount of time" to heat death of the universe but I didn't want to be accused of being TOO pedantic. One needs to maintain decorum, there are strict RefDesk standards for the level of pedantry deemed acceptable. ;) Zunaid 17:45, 16 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)

Hey guys, thanks alot! I'll try some of the topics you suggested like networking and GUI. I'm kind of familiar with awt and swing components. I'll also try and look over the Haskall programs. I got bored just learning Java because I wasn't doing anything with it, but next year I'll enter college so I could continue it there I guess. Thanks again. 66.133.196.152 (talk) 03:13, 17 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[1][2]. --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)

I see, thanks! 70.29.24.251 (talk) 16:30, 16 March 2010 (UTC)

Resolved

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)

If you had read the above you would see that its because each of the hundreds of files has around 360kb of more or less identical unwanted text to discard, leaving just a few short lines that I'm interested in. When I've found a way to dispose of the 360kb of garbage in each of the several hundred files, then I may start thinking about putting what's left in a database. You seem to be presupposing that I'm a programmer - I'm not, so what you write is completely meaningless to me. But thanks for your good intentions. 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)

Thanks, but I'm not a programmer so you'd need to explain that a lot more for me to be able to use it. 78.147.248.108 (talk) 16:25, 16 March 2010 (UTC)

First, you need a perl installation. I use Cygwin, though that's overkill if you don't need a full unix environment; I've seen Activeperl (download page) recommended to people who just need a perl binary for Windows, though I haven't tried it myself. Pick a regex that matches the line above the text you want saved, and another that matches the line under it, and use those to replace the REGEX_THAT_MATCHES_'s. Then, for each file you want to process, do something like perl -ne 'next if (1 ../FIRST_REGEX/); last if (/SECOND_REGEX/ .. 1); print;' <inputfilename >outputfilename in a command window. —Korath (Talk) 07:22, 17 March 2010 (UTC)

Hopefully OP has not given up hope! No need to overcomplicate with regex, SQL databases, Cygwin or perl. The following code works with AutoIt, freeware scripting software that I use to automate everyday tasks. All you'd need to run the code would be to install AutoIt and save this code as a text file with the .au3 extension.

#Include <File.au3>
Local $array
$folder = FileSelectFolder("Select folder with your text files", "")
$keepline = InputBox("Starting text", "What is your starting text? (case sensitive)")
$lastline = InputBox("Ending text", "What is your ending text? (case sensitive)")
$file_name = _FileListToArray($folder, "*.txt", 1)

For $x = 1 to $file_name[0]
	$textfile = $folder & "\" & $file_name[$x]
	_FileReadToArray($textfile, $array)

	For $y = 1 to $array[0]
		If StringInStr($array[$y], $keepline, 1) Then
			While Not StringInStr($array[$y], $lastline, 1)
				$y += 1
			WEnd
			Do
				$y += 1
				$array[$y] = Chr(0)
			Until $y = $array[0]
		Else
			$array[$y] = Chr(0)
		EndIf
	Next

	_FileWriteFromArray($textfile, $array, 1)
Next

A simple explanation of what the code does: It will open a prompt for you to select a folder. It will then ask you for the text strings marking the start and end of the block you want to preserve. It will then go through every .txt file in the folder you selected, removing anything before and after the sections you've specified. It's quite fast, but only tested by me, so please back up the text files before trying this out just in case :) I know you don't have programming experience, but it really is as simple as installing Autoit and running this code. You can compile this with Autoit into an .exe if you like. Please let me know if you have any questions. Coreycubed (talk) 16:23, 18 March 2010 (UTC)

Thank you. I tried the script, but got an error message:

"Line 8 (File "C:\.....yourscript.au3"):

For $x=1 to $file_name[0]

For $x=1 to $file_name^ERROR

Error:Subscript used with non-Array variable."

What can be done to fix this please? 78.147.148.36 (talk) 17:16, 20 March 2010 (UTC)

I found that that problem was due to using it in a folder without any text files. I did the correct folder and it worked, thanks very much. The only slight quibble I have was that it left the before and after text strings there rather than deleting them. It would be a useful script to compile and release into the freeware domain, as there seems to be nothing else that can do what it does. Thanks again. 78.147.148.36 (talk) 19:12, 20 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)

I don't think my IP address changed. This doesn't explain why the computer froze and I had to turn it off, either the first time or the second time. My session didn't time out, but if I turn off the computer, it's not one of those sites that will keep me signed in because I've never asked it to.Vchimpanzee · talk · contributions · 13:27, 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)

Of course, mp3 is a lossy compression method, so direct application of the nyquist limit isn't exactly valid. The frequency spectrum has been sparsified for storage based on the (nonlinear, heuristic) mpeg audio algorithm, which is designed with attention to the subjective, psychological effects of acoustic perception. So, even if there are only 5 kHz of actual, real information in an mp3 data stream (as limited by the bit-rate and the practical realities of information theory), it can be "re-inflated" to a 22kHz audio signal. Thus, it's better to talk about "quality" or accuracy (say, Mean Squared Error of the reconstructed samples), rather than the true frequency bandwidth of the signal. Nimur (talk) 15:42, 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 —Preceding unsigned comment added by 61.46.19.68 (talk) 11:39, 16 March 2010 (UTC)

I'm not sure the response immediately above is from the OP. The IP address is very different from the first and they resolve to different continents.

A couple of other things to check: As the problem occurs early on in the boot process (the Windows startup sound is affected), maybe it is a sound driver problem; using the device manager, try rolling back or updating the sound driver. Also worth checking is whether you have blown the speakers; very high volume sounds can physically damage speakers and, depending on the specific wiring, the fault might not be audible through headphones. Astronaut (talk) 14:16, 16 March 2010 (UTC)

Or you could simply not have enough RAM to do more than just one thing. This happened to me until I added more RAM.  Buffered Input Output 15:39, 17 March 2010 (UTC)

March 16

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 [3].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)

This is not a very well-asked question; please give more information, on context, etc. Is this an assignment for homework/coursework?

Manufacturer's Recommended Price isn't calculated, it's chosen (see the similar suggested retail price); ROT%=Return on turnover is profit divided by turnover. No idea what ED stands for (Excise duty or exempt from (excise) duty?), or D%; RATE or AMOUNT if they're not acronyms could be anything. --Normansmithy (talk) 12:04, 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)

Thank you!   :-)
--Seren-dipper (talk) 21:53, 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)

It's also not going to be 100% anonymous, because afaik, that doesn't exist. --Wirbelwindヴィルヴェルヴィント (talk) 21:35, 17 March 2010 (UTC)

You should provide more information... TOR only is a poor solution. Most plugins will leak your real IP address, especially flash. I should use vidalia TOR (its a version of TOR - with the firefox plugin) AND proxifier. Set it up correctly though.

Get the installation bundle for TOR here: http://www.torproject.org/easy-download.html.en And the guide here: http://www.proxifier.com/mac/documentation/pgs2/tor.html Proxifier is not free though, but it does have a free trial on the same web site as the guide. There are alternatives though —Preceding unsigned comment added by 76.169.33.234 (talk) 05:01, 18 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)

In your shoes the way I would do it would be to download some free video editing software, and do a trial and error of matching the audio track to the video, moving the audio forward and back relative to the video, until I got the best match. 92.24.123.30 (talk) 20:08, 16 March 2010 (UTC)

Message is driving me around the bend

File:LAN-unplugged.png

Every five minutes this pops up and then goes away. Been doing this for some time now. Windows XP, Dell Dimension 2400, 8 gigs, 700+ ram, Firefox. There are no dead ended connections to my computer. Obviously I'm online without problem. Two questions: Does this refer to anything real? And how do I turn it off?--Fuhghettaboutit (talk) 12:40, 16 March 2010 (UTC)

There's an option in Powertoys for Windows XP to turn the bubbles off; but you need to download powertoys in order to do so. --Tagishsimon (talk) 12:43, 16 March 2010 (UTC)

Thanks for the tip Simon. I'm a bit wary of downloading yet another program. Any direct way; some change in my settings; something direct?--Fuhghettaboutit (talk) 13:05, 16 March 2010 (UTC)

It's a microsoft program; and as far as I know, is the only way to do it. (Okay, there's probably a registry hack, but I don't know what it would be.) I'd positively advise you to get it installed, since it gives you more control over your XP environment, which is exactly what you're after. --Tagishsimon (talk) 13:20, 16 March 2010 (UTC)

I'd go into your network hardware display and make sure you've disabled anything that you're not using - it's unlikely to be actual hardware, probably a driver thing or something. Ale_Jrb^talk 13:34, 16 March 2010 (UTC)

Although you could turn off the bubbles, I've never heard of this happening unless it IS a hardware issue and if so you're really just hiding the problem instead of fixing it. Because you're not getting kicked off the net it sounds like a very tiny disconnection which might be driver related, but I'd try changing your network cable as well as checking that the switch/router you're plugged into isn't the one that disconnecting/reconnecting. ZX81 ^talk 13:54, 16 March 2010 (UTC)

(ec) As for why you might be getting that message, perhaps there is a tenth of a second interruption periodically, which causes the bubble to pop up, but which isn't long enough to cause any noticeable disruption in whatever you're doing. The ideal solution would be to turn down the sensitivity so that it only reports a disconnect after maybe 5 seconds, but I don't know if you can do that. StuRat (talk) 13:57, 16 March 2010 (UTC)

Probably you have two network connections; the one you use and an extra one you don't use. The unplugged messages are correct because one of the connections your are not using. To turn them off go to network connections in control panel, right click the one that shows it's unplugged and click disable. That'll turn the messages off —Preceding unsigned comment added by Fire2010 (talk • contribs) 13:59, 16 March 2010 (UTC)

Agree with with Fire2010 above, there always seem to be weird "extra" network ports somehow installed. Another thing you can try is to go into your network connection's "Properties" dialog and untick "Notify me when this connection has limited or no connectivity". However I found that Windows sometimes ignore that setting and annoyingly notifies you anyway. As for Tagishimon's advice, I will heartily recommend installing TweakUI (the part of Power Toys that deals with this setting). I've just tested it NOW and it works. You need to go to the "Taskbar and Start Menu" setting and untick "Enable balloon tips". Note this will disable ALL balloon tips that you normally get in your taskbar. Zunaid 15:05, 16 March 2010 (UTC)

Am monitoring from work. I will try try solutions offered once I get home. Thanks for all the responses.--Fuhghettaboutit (talk) 17:24, 16 March 2010 (UTC)

Go to Start --> Run and type ncpa.cpl. Then, right-click on your connection and select "Properties." Then try unchecking the box at the bottom of this dialog: [4].--Chmod 777 (talk) 23:57, 16 March 2010 (UTC)

Shortcuts for Special Characters On a Mac

Can anyone give me a list of shortcuts on a mac so that I can type foreign characters? Specifically language-related characters in French and German (éàçü etc....)

Many thanks Lucas 83 14:27, 16 March 2010 (UTC) —Preceding unsigned comment added by Lukerees83 (talk • contribs)

here you go. Found by just Googling "special characters mac". --Mr.98 (talk) 15:13, 16 March 2010 (UTC)

find total number of results for a Google search string

Resolved

How can I make Google display the total number of results for a particular search? Formerly it used to be displayed as x-xxx of total xxx. Now it is not seen. --Virbanu (talk) 15:36, 16 March 2010 (UTC)

I don't understand. Google works just as before: Here is my test which shows "Results 1 - 100 of about 161,000,000 for "this is a test". (0.38 seconds)" near the top of the screen. Astronaut (talk) 16:02, 16 March 2010 (UTC)

yest, got it. thank you. --Virbanu (talk) 17:17, 16 March 2010 (UTC)

Blocking all incoming external email for certain addresses in Postfix

Hey guys. I have a serious spam problem going on here where I work. We have several internal aliases to facilitate internal communication (each area has its own alias, there's an alias for the entire company, etc.)

The problem is, those emails leaked, and we're getting lots of spam through them. The spam comes from local companies, so it's not really blocked by the usual spam systems we have in place. Either way, a quick solution would be blocking all external incoming email addressed to some specific aliases, but not all of them (some need to receive external mail). Is this possible in Postfix?

Thanks in advance! -- Lucas —Preceding unsigned comment added by 189.112.59.185 (talk) 18:33, 16 March 2010 (UTC)

Inkscape: import PDF

Hi. I'm trying to import a PDF to Inkscape. It gives me an "option" Import text as..., though the only possible answer is text. Does anyone know of a way to vectorise the text/font into a path and import the page like that? ╟─TreasuryTag►Africa, Asia and the UN─╢ 19:39, 16 March 2010 (UTC)

Open, don't import. -- Finlay McWalter • Talk 20:03, 16 March 2010 (UTC)

Precisely the same effect... ╟─TreasuryTag►Not-content─╢ 20:10, 16 March 2010 (UTC)

Try the sample PDF from samplepdf.com; it opens and is editable fine in Inkscape v0.47 (Inkscape 0.47pre4 r22446, built Oct 14 2009) on Ubuntu Linux x86. -- Finlay McWalter • Talk 20:28, 16 March 2010 (UTC)

Nope, no good. Using 0.47 on Windows 7... ╟─TreasuryTag►voice vote─╢ 21:14, 16 March 2010 (UTC)

Works fine for me in Windows 7 (I tried two versions - Inkscape 0.46, built Apr 1 2008 and Inkscape 0.47 r22583, built Nov 21 2009) on these two PDFs: http://samplepdf.com/sample.pdf and http://www.mda.mil/global/images/system/thaad/38112.pdf If you can't open either, that error message would suggest that the PDFs are getting mangled in transit. md5sums for these two files are as follows:

• 8CCC6CC514BD3A50A33FCA72569B36F6 sample.pdf
• 91A1B8987251CD0A3A169FD8C8195850 38112.pdf

If not, maybe you have a bad Inkscape installation, and should do a thorough remove and reinstall. -- Finlay McWalter • Talk 22:31, 16 March 2010 (UTC)

Before Inkscape added their (sometimes iffy) PDF reader, I used texterity to convert a PDF to SVG whick Inkscape liked (e.g. File:Wfm thaad diagram.svg). -- Finlay McWalter • Talk 20:34, 16 March 2010 (UTC)

Typing special characters on Windows?

When using Linux, I'm used to being able to type special characters by holding down the AltGr or AltGr+Shift keys and typing numbers or letters. For example: əbcð€fghıjĸŋœrßþuvw×yʒ. That was what happened when I held down the AltGr key and typed the letters from a to z. And what's even more special, I can use the caret (^) to type superscript numbers, for example ²³ can be typed as caret, 2, caret, 3.

But when I tried the same on Windows, pretty much nothing worked. If I want a special character, I have two choices:

1. Try to remember the numeric character code and type it on the numeric keypad while holding down the AltGr key.
2. Call up the Character Map application and copy&paste the character with the mouse.

Neither of these is as easy as it is with Linux. I find it surprising Microsoft hasn't come up with such a simple idea as this is. Is there some hidden configuration option on Windows I need to enable to have this? Or is there some sort of third-party application to do this? JIP | Talk 19:54, 16 March 2010 (UTC)

Another option is to set up the Language Toolbar to easily swap between multiple keyboard layouts. Typically, the first step is to make sure that alternate language input is installed and enabled. See How To Add and Enable Additional Languages in Windows; depending on where and how you got your Windows system, "foreign languages" may already be installed and enabled; or installed, but not enabled yet. (In some rare cases, you may need your original Windows installer CD to install language support). Then, see HOW TO: Use the Language Bar in Windows XP, Windows Keyboard Layouts, and this set of language bar keyboard shortcuts once you have multiple layouts set up. With this arrangement, one or two keystrokes can put you into a Greek, Cyrillic, Arabic, or indeed any other supported language / alternate glyph mode in Windows. Nimur (talk) 21:25, 16 March 2010 (UTC)

The thing is, I use an exactly same labeled keyboard layout ("Finnish/Swedish", as Finnish and Swedish keyboards have identical layouts) in both Linux and Windows. In Linux, the AltGr-key combinations I described above work. In Windows, they don't. I don't want to use an entirely foreign keyboard layout just to be able to type some special characters. Heck, I can't even type "²" or "³" in Windows without calling up the Character Map application. In Linux, I can do it in two keystrokes, like I just did a minute ago, in much less than one second. I want to know how I can do that in Windows. JIP | Talk 21:32, 16 March 2010 (UTC)

Some versions of Windows use CTRL+ALT to represent ALT GR - so you can try to see if this works for you. On many Windows systems, CTRL+ALT is automatically aliased to the non-existent "AltGr" key. For example, see Why Ctrl+Alt shouldn't be used as a shortcut modifier. As you can see from our AltGr key article, though, the concept of an AltGR is sort of limited. Windows, with variations among different internationalized versions, does have support for the emulated CTRL+ALT or RIGHT ALT to correspond to the AltGr concept. However, Windows takes the view that alternate inputs really should not be chorded key inputs like this - because it is confusing and results in unexpected behaviors for most users. That is why the alternate keyboard input scheme was invented, and it's really a preferred method for Windows internationalized character input, because it is totally unicode compliant and supports arbitrarily many different alternative glyph input schemes. Ultimately, with the keyboard shortcuts, you can still do this in as few as two or three key-presses (exactly as many keypresses as the AltGr method on Mac or Linux or Solaris - but with a different shortcut combination for any particular glyph). Nimur (talk) 21:40, 16 March 2010 (UTC)

See also, this MSDN blog about AltGr on Windows, discussing technical and usability issues. Nimur (talk) 21:45, 16 March 2010 (UTC)

If you don't like any of the keyboard layouts that come with Windows, you can make your own with the Microsoft Keyboard Layout Creator. —Bkell (talk) 21:54, 16 March 2010 (UTC)

This is all very nice when it comes to letters used in foreign languages, as a specialised keyboard layout does indeed serve them better. But some of the special characters, indeed the ones I need to use the most, are typographical and mathematical symbols, not letters. For example, "²" and "³" like I mentioned above. The image File:KB Sweden AltGr.svg contains many characters I'm used to be able to type in Linux without thinking twice about it, and whenever I use Windows, I end up thinking "damn, this is Windows, I need to use the Character Map". Even if the AltGr key and the Ctrl-Alt combinations should not be used anywhere because they will only confuse the user, I can still type "²" and "³" in Linux as caret, 2 and caret, 3 without ever needing to touch the Alt or AltGr keys. In Windows, I can't. Is this because Microsoft has an official policy that shortcuts for typing special characters directly on the keyboard must be discouraged or has no one at Microsoft just thought about it? JIP | Talk 21:59, 16 March 2010 (UTC)

It is because Microsoft Windows is a general purpose computing operating system, and the engineers at Microsoft (or indeed, anywhere) can not possibly know which of the 300,000 valid unicode glyphs you are going to need commonly. See Unicode#Input_methods and Unicode input. It is actually very complex - and I think you're expecting a lot for the operating system to magically know which characters you want hotkeys for. Windows (and the other major operating systems) allow you to customize keyboard layouts and shortcuts - and Windows does this with the methods I have linked to above; but it's really impossible for the operating system to come pre-loaded knowing that you are a Finnish / Swedish / English user with occasional need for mathematical symbols (as opposed to, say, a German / English / Japanese user with occasional need for Greek alpha/beta/gamma characters). More than likely, your Windows was localized based on the "lowest common denominator" keyboard needs for some semi-arbitrarily chosen "marketing region". And if you want more customized key inputs, you can configure additional keyboard layouts and easily swap between them with a single keypress, or using the mouse, or using the control panel, as I described above; and if you want more customization than that, and you are going to need to design a custom keypad with thousands of buttons. Nimur (talk) 22:17, 16 March 2010 (UTC)

I will suggest again that you try the Microsoft Keyboard Layout Creator. If you want lots of typographical and mathematical symbols available, make a keyboard layout that has them. If you want the caret to be a so-called "dead key" for producing superscripts, make a keyboard layout that does that. —Bkell (talk) 01:24, 17 March 2010 (UTC)

It seems that the specific issues JIP wanted (Right Alt acts as AltGr, and easy-to-use superscript 2 and 3, for example) are supported in the Windows "German IBM Keyboard Layout", as well as many other European layouts (Finnish, Swedish, Sami, etc). If JIP sets this to be the default keyboard layout, it may solve all of their problems. Nimur (talk) 01:36, 17 March 2010 (UTC)

Perhaps I'm mistaken but wasn't JIP's complaint that he/she was using the Swedish/Finnish layout in Windows but it wasn't doing what he/she was used to from Linux, which included this superscript thing? Nil Einne (talk) 16:25, 19 March 2010 (UTC)

March 17

Important

How do u get your friends back on page when it has been wiped out for some reason and what is a number to call for assistance? —Preceding unsigned comment added by 68.242.119.194 (talk) 00:41, 17 March 2010 (UTC)

Gonna need more details than that, what exactly are you talking about?--Jac16888^Talk 00:45, 17 March 2010 (UTC)

You might know what you're on about, but we have no idea unless you provide more details....Chevymontecarlo. 15:43, 17 March 2010 (UTC)

home network - slow speed for 1Gb

My new 1Gb home network is performing at only about 20%.

In my home network I replaced a 10/100 wired router with a 1Gb wired/802.11n wireless router. Before I made the change I timed the transfer of a 338MB file. It took about 37 seconds. One computer already had a 1Gb Ethernet card, with a cheap cat-6 cable. I put a 1Gb Ethernet card in another computer. (It still had a cat-5 cable.) I tested the transfer several times and it took 17 to 22 seconds - about twice as before but about 5 times slower than I thought it should be. I replaced the cat 5 cable with a cat 5e cable - no noticeable difference in speed.

I replaced the cat 5e with a high-quality cat-6 cable and restarted the router. (The other computer has the cheap cat-6 cable.) Now the transfer took less than 5 seconds - the speed I was expecting. (Note: I did this test only one time so it is possible I copied the wrong file.)

Now, about 12 hours later I tested again and it is back to 17-22 seconds. I restarted the router - same speed.

The router shows that both computers are connected at 1Gb. The Netgear utility shows both connected at 1Gb. The Netgear utility also shows the transfer performance at 18-19%, which agrees with what I measured.

Why am I getting only about 20% performance? Could the problem be the cheap cat-6 cable? Bubba73 ^{(You talkin' to me?)}, 05:13, 17 March 2010 (UTC)

It's possible that the network isn't your bottleneck; a nearly-full, highly-fragmented, or just poorly-performing hard drive could easily only be able to manage 20MB/second sustained write speeds. —Korath (Talk) 07:29, 17 March 2010 (UTC)

Though, having reread what you wrote, it's more likely that it's on the sending end—338MB will probably fit into ram cache, so the slow first send indicates a slow read from the hard drive, and the repeated test is sending it from your source machine's read cache. If this is the problem, then you can expect the first test to be slow, and a subsequent repeat test to be limited only by your network, even if you don't reboot your router in between. You probably want to be benchmarking with larger files, certainly ones larger than the amount of ram you have in either machine. —Korath (Talk) 07:42, 17 March 2010 (UTC)

Repeated tests are not significantly faster. Bubba73 ^{(You talkin' to me?)}, 15:18, 17 March 2010 (UTC)

My first suggestion is to make sure jumbo frames are enabled on both computers, assuming that the Netgear router supports jumbo frames. There is often a jumbo frames setting in the device driver settings for the ethernet interface, which you can get to through Device Manager. But it's unrealistic to expect to get anything close to 1 Gbps of actual throughput on most gigabit hardware, especially if hard drives are involved; see this Coding Horror blog entry for example, or this more recent Tom's Hardware article. -- Coneslayer (talk) 11:28, 17 March 2010 (UTC)

I don't think it is entirely the hard drives. One computer has two SATA drives and the other has two ATA drives. On the one with two SATA, I can copy the file to the same drive or to the other in a couple of seconds. On the one with two ATA drives it takes under 10 seconds to copy to the same drive or to the other drive. But it is somewhat faster copying from the ATA to the SATA than the other way around. The SATA to ATA gives about 18-19% network performance and ATA to SATA gives about 25% network performance. But still the network performance is about half of the HD to HD performance on the old ATA drive-to-drive. Bubba73 ^{(You talkin' to me?)}, 15:16, 17 March 2010 (UTC)

Both cards had jumbo cache disabled so I enabled it. No improvement. I rebooted both computers and the modem. I also disabled Firewire (because I don't use it), and now it is up to about 24% from 18-19%. Bubba73 ^{(You talkin' to me?)}, 15:47, 17 March 2010 (UTC)

Tom's Hardware article was extremely informative. The HD must be the bottleck. He said to expect 20-65MB/sec, and I'm getting approximately the low end of that range. One of the machines is old with the old ATA drives, so that seems to be what I can expect. My thanks to everyone.

Resolved

Bubba73 ^{(You talkin' to me?)}, 16:04, 17 March 2010 (UTC)

"Ticking" HDD

I recently bought an external drive (1.5TB, Seagate) and it sporadically makes loud ticking noises when turned on. Usually when first turned on it will do it for about 30 seconds, during use it will start ticking maybe once every 15 minutes, giving it a large read/write job seems to stop it temporarily.

It's the same sound I've heard from drives with "crashed heads" (not sure if thats the correct term) so it's giving me some angst ... is it defective? I assume it's the heads banging into the case or something thats making the noise, that can't be good for it. Will it die completely soon? I'm loath to send it back since it has more than 1TB of data on it so I'd need to buy a new drive to put all the stuff on while I sent this one away to get replaced/fixed but obviously I have to, just hoping for a second opinion or an alternative. Thanks Benjamint 07:58, 17 March 2010 (UTC)

Ticking is indeed very often a sign of drive failure. It would be a good idea to run a badblocks test and some S.M.A.R.T. self-tests. If either of those return any errors, it's best to replace the drive ASAP, as any further use will likely aggravate the problem. If all the tests come up clean, the drive might still be good - but if you keep it, be sure to periodically repeat those tests. --Link ^(t•c•m) 11:22, 17 March 2010 (UTC)

Sounds suspiciously like the Click of death. You should immediately back up all important information--I wouldn't trust a hard drive that is making that sound. --Zerozal (talk) 17:20, 17 March 2010 (UTC)

Ticking is bad. Backup now. Shadowjams (talk) 21:11, 17 March 2010 (UTC)

Is it only damaging itself or at risk of dying when it is actually ticking? With about 1.2TB of data to copy over it would need to be running for several hours... should I do it incrementally in order to not tax it too much? Or since it doesn't seem to tick when it's reading/writing is it actually functioning normally during the backup processs? Benjamint 21:18, 17 March 2010 (UTC)

It's hard to know what exactly the "ticking" sounds like. It's conceivable that it's just a loud platter, but most rhythmic sounds from a HD, especially a modern one (which are usually quiet), is cause for concern. I think it would be prudent to backup in that instance. It's possible that reading sections could damage them, but that data's in jeopardy anyway. You have to use your own judgment, but in my experience, new drive sounds always precede a crash; I would prioritize the most important data first for backup and hope for the best. Shadowjams (talk) 03:27, 18 March 2010 (UTC)

My drive has been "ticking" (1 tick every few minutes when it is idle) for 3 years, and it's fine. --169.232.246.115 (talk) 08:52, 18 March 2010 (UTC)

This type of ticking could be the disk powering down after a certain time. Maybe a background process wakes it every minute or so. If you listen very carefully you might be able to hear if there is less motor noise before or after the click, though drives are usually much quieter than cooling fans so you might not be able to tell. -- Q Chris (talk) 10:00, 18 March 2010 (UTC)

Keys suddenly not working

a e h l m r and w. What should I do please? - Kittybrewster ☎ 10:43, 17 March 2010 (UTC)

Turn off. Unplug the keyboard. Turn it upside down and shake out the gook. Replug the keyboard. Try again. If that fails, get a new keyboard. (Did anything else happen? No accidents with liquid, for instance?) --Tagishsimon (talk) 12:46, 17 March 2010 (UTC)

Step 1 and 2 are optional. Step 4 is fairly cheap nowadays.--Stephan Schulz (talk) 12:57, 17 March 2010 (UTC)

You could try prying off the key tops with a flat-head screwdriver (or similar tool) and clean under there. You can also get cannisters of compressed gas for cleaning a keyboard, but it's probably as cheap to buy a new keyboard. Note that this advice and the previous applies to a desktop PC with a separate keyboard; you don't say what sort of keyboard it is.--Normansmithy (talk) 17:01, 17 March 2010 (UTC)

(Laptop). Success! Oh joy. Thank you. - Kittybrewster ☎ 17:30, 17 March 2010 (UTC)

Just curious...which action fixed it ? StuRat (talk) 23:10, 17 March 2010 (UTC)

Handed it to girlfriend who cleaned it. - Kittybrewster ☎ 09:16, 18 March 2010 (UTC)

Using the "turn it upside down and shake vigorously" method ? StuRat (talk) 15:33, 18 March 2010 (UTC)

Regarding buying new keyboards - I actually clean my keyboards even if a new (used but still) unit will cost me less than a kebab, because this just generates less electronic waste. Take apart. Wash all non-electronic components with dishwashing liquid. Put back together. --Ouro (blah blah) 07:46, 19 March 2010 (UTC)

Greasemonkey Question

Is it possible for a greasemonkey script to make the browser load a url? How would you do this? Thanks --Fire2010 (talk) 15:35, 17 March 2010 (UTC)

That is an example of cross-site scripting, and because it represents an inherent security risk, GreaseMonkey has limitations about what you can do with it. See this forum post and this documentation for GM_xmlhttpRequest. (Compare with the standard JavaScript XMLHttpRequest. For more information about this issue, see the Same Origin Policy from Mozilla's developer website. Nimur (talk) 15:56, 17 March 2010 (UTC)

I gave this query a suitable title. --Sean 18:00, 17 March 2010 (UTC)

Windows networking / Samba and subnets

I'm trying to understand the interaction between windows/samba file-sharing/workgroups and the local subnet. Specifically my question is, can I share files on a LAN, with a basic windows setup (no master domain controllers or anything advanced) between machines on different subnets? Is it that they don't see each other because they simply don't receive the broadcast messages?

Obviously these packets don't get routed by most ISPs, but is that because ISPs block them or because a NATed network will have a different subnet (and in which case, if a client wasn't NATed, would they be able to share with that non-private subnet?). I'm not so much looking for a specific answer so much as I'm trying to understand how these two interact, so any push in the right direction would help. Shadowjams (talk) 19:01, 17 March 2010 (UTC)

To the first part of your question: yes, that's right. In that scenario, if you type \\192.168.2.10 (or whatever; the ip address of the other machine) in your Explorer location bar, you should still be able to reach it directly. It's just that Windows discovers nearby hosts by using NetBIOS name resolution, which broadcasts on the local subnet. If your DHCP server also incorporates a DNS server, or if you manually add the hostname/ip pairs to your Hosts file, you should be able to access it by name, although I don't think Windows will be able to discover them automatically.

To the second part, there's a couple issues. As I mentioned, netbios name broadcasts are local subnet broadcasts, so they won't make it onto the internet. And yeah, a lot of ISPs might block SMB traffic. The main reason there isn't to block file sharing, but because there are a lot of viruses and worms that target the SMB and netbios ports, since they're open on a lot of Windows machines by default. But if you weren't NATed, and your ISP didn't block it, then you should be able to do \\208.80.152.2 or whatever, and be able to reach it. Indeterminate (talk) 03:36, 18 March 2010 (UTC)

Very helpful. Thanks. Shadowjams (talk) 03:57, 18 March 2010 (UTC)

One DVD won't play in laptop

Hi. I'm running a Windows 7 Dell laptop. I recently bought a new DVD boxset, and it won't work in the laptop: I put any of them in, the noises cycle round and round and round, but it won't show up or function. Other DVDs work perfectly, and the "defective" DVD is perfect in a desktop PC and in a DVD-player. Any ideas on what's up? ╟─TreasuryTag►assemblyman─╢ 19:18, 17 March 2010 (UTC)

Pardon me, have just clarified: of the six DVDs, numbers 1, 4 and 6 are subject to the problem listed above; the others work perfectly... :O ╟─TreasuryTag►Counsellor of State─╢ 19:27, 17 March 2010 (UTC)

You didn't state the title. A web search might reveal others with the same issues— bad batches have occured. ---— Gadget850 (Ed) ^talk 19:55, 17 March 2010 (UTC)

No, tried that – no such luck. Since it works on seemingly every other device, however, I'm not sure it's going to be the DVD's "fault"... ╟─TreasuryTag►belonger─╢ 20:09, 17 March 2010 (UTC)

If you're using some horrible DVD playing software that Dell preinstalled, or Windows Media Player, all bets are off. Try with VLC or SMPlayer, or try making an image first with dd or ddrescue. ¦ Reisio (talk) 22:22, 17 March 2010 (UTC)

If the disk doesn't even show up in My Computer, you won't be able to make an image, and other media players won't help either. If the disk really doesn't show up in My Computer at all, it sounds like you might have a defective DVD drive, which you should talk to Dell Support about. Indeterminate (talk) 00:12, 18 March 2010 (UTC)

Google Earth

It may be my own ignorance - probably the case as usual - but whenever I use the latest version of Google Earth and narrow down to the desired location - and then click on the chosen "bubble", everything works fine. The bubble rotates and points me up or down the desired street or whatever, and then offers me a chain of cameras. I soon discovered that if I try to leapfrog to a distant camera further away than the closest in view, the system will crash and I will get an error message and have to start over. So I now don't do that; instead, I religiously move from the closest camera to the next furthest and so on - but I still invariably crash the system and get a message that says, "Google has discovered a system error" or suchlike. Is it me or is it something else I am unaware of? I really would like to know as I really enjoy using Google Earth but the interruptions are spoiling it for me. Thanks folks. 92.2.71.61 (talk) 20:00, 17 March 2010 (UTC)

Well, it sounds like you've found a bug. It could be due to:

• a bad install of the program - you could try to fix this by uninstalling and reinstall Google Earth,
• some configuration problem on your computer, maybe a driver or a library or something. If this is the issue, you might have to reinstall your OS to fix it.
• a bug in Google Earth - if you try this same thing on another computer, and it does the same thing, this is probably the issue.

If it turns out to be the last one, you can report a bug and hopefully Google will fix it in a future release. Indeterminate (talk) 00:09, 18 March 2010 (UTC)

.exe to .dmg

How can I convert a .exe file for windows to being accesible on an Apple Macintosh? Do I need to convert to .dmg? What program can I use to do so? —Preceding unsigned comment added by 76.31.145.125 (talk) 20:14, 17 March 2010 (UTC)

Could you explain what exactly you want to do with the .exe file when you say "accessible"? If you want to run a Windows executable file (like HalfLife.exe, for example), it won't work, because the .exe file format is specifically designed to run under a DOS or Windows operating system. Comet Tuttle (talk) 20:18, 17 March 2010 (UTC)

That's too strong. There are various emulators for running Windows executables on things other than Windows. See VMware Fusion and Parallels Desktop for some MacOS ones. --Sean 20:41, 17 March 2010 (UTC)

Also, if you tell us what program you are interested in someone may know of a Mac port.131.111.185.69 (talk) 21:06, 17 March 2010 (UTC)

.EXE files are generally compiled to work only on Windows machines. There is no one-step solution to running them on a Mac—they are compiled for a different operating system. They cannot be just easily converted into one another. The two major ways for running Windows programs on Macs are either

1. through a virtual machine (e.g. VMware Fusion, Parallels Desktop, VirtualBox), in which you basically run Windows itself as a program in the Macintosh, and the EXE in that virtual instance of Windows (advantage: pretty easy to set up, if you have an extra copy of Windows; disadvantage: you're running two operating systems at once and that is much slower than just running one of them),
2. through a dual-boot system (BootCamp), whereby you run Windows itself on your Mac hardware (advantage: quicker than virtualization because you're running Windows and only Windows; disadvantage: a bit harder to set up, opens your main computer up to all of the "dangers" of Windows, computer needs to be rebooted every time you want to switch between operating systems).
3. there is also Wine, which manages to somehow run Windows applications more natively in a Mac OS, but the few times I tried to get it to work, it seemed rather impossible even if you were pretty well experienced with the Unix aspects of Mac OS X. (Maybe it has gotten easier. But if you're asking whether EXEs can be converted to DMGs, you are probably not better in this respect than I was.)

And of course the other option altogether is to try and find a version of the program that has been compiled specifically to run on a Mac, which may or may not be possible depending on the program. --Mr.98 (talk) 21:31, 17 March 2010 (UTC)

All correct except part of your first point. Modern virtualization solutions like e.g. the free VirtualBox are running the virtualized OS at very nearly native speed. You will only lose significant performance if you are short on memory, if the host OS is running additional resource-intensive tasks, or if you rely on some hardware that is not supported by the virtualization. I'm e.g. running Ubuntu with VirtualBox on MacOS-X, and its indistinguishable from a native install. --Stephan Schulz (talk) 12:34, 18 March 2010 (UTC)

Put simply - there is literally no way to turn a Windows EXE into a Mac DMG - that's really impossible for all sorts of technical reasons. What you have to do is to find a way to persuade the Mac to behave sufficiently like a Windows machine that it'll run the EXE "as is" - and previous posters have explained that very well. SteveBaker (talk) 09:10, 19 March 2010 (UTC)

Win 7 - opensource and/or free video editing software?

First, thank you to everyone who posted answers to my question a week back about bulletproofing my mother-in-law's new Win7 PC. That went very well! As a follow-up, I'd like to know if anyone has a particular opensource and/or free video editing software they can recommend for Windows 7? My dear M-i-L has dreadfully boring charming digital videos of her 2 cats that she'd like to edit... 61.189.63.170 (talk) 22:14, 17 March 2010 (UTC)

The best place to start are our articles on video editing software, List of video editing software, Comparison of video editing software. Nimur (talk) 22:23, 17 March 2010 (UTC)

Windows Movie Maker? ¦ Reisio (talk) 22:24, 17 March 2010 (UTC)

These days, most video cameras come with some basic video software on a CD. Depending on the model, that will simply let you copy the video off the camera, or also provide some editing capability. Alternativly, the camera manufacturer might have something you can download from their official site. As mentioned above, Windows has a basic tool installed by default and there are others available. In my experience, using the software provided with the camera and Windows Movie Maker has proved acceptable for my purposes. Astronaut (talk) 23:06, 17 March 2010 (UTC)

As the Windows Movie Maker says, Windows Movie Maker has been replaced by Windows Live Movie Maker in Windows 7. --169.232.246.115 (talk) 08:51, 18 March 2010 (UTC)

March 18

Game development - relative profit now vs then?

Reading about Zork, which was developed by ~4 dudes, made me wonder about the relative profitability of pc/videogames over time. Clearly development costs & team headcounts have skyrocketed in the past 30 years, but gaming is now a 6(8?) billion dollar industry in the US. On relative terms (revenue/cost as a %) is it getting more or less lucrative on average to make PC/videogames? 218.25.32.210 (talk) 05:29, 18 March 2010 (UTC)

It must be more. Normal people who surely scoffed at gamers only 5-10 years ago are now playing World of Warcraft, and paying a monthly fee to do so. ¦ Reisio (talk) 06:02, 18 March 2010 (UTC)

Yeah but how many dozens of MMOs have been outright failures? For a reasonable analysis you've got to include all ventures, not just the phenomenally successful ones. 218.25.32.210 (talk) 06:46, 18 March 2010 (UTC)

Paging SteveBaker --Tagishsimon (talk) 06:03, 18 March 2010 (UTC)

This topic is summarized at video game industry under Economics. The stuff about the current market is unreferenced and most likely based on anecdotal evidence instead of real data. Basically, the video game industry is like any other entertainment industry now. To make a blockbuster hit, it takes tons of people. There are cases where a small indie group get lucky with a big hit - which is nowhere near the size of the big-budget blockbusters, but still profitable. There are many failures and a lot of fear - causing tons and tons of repetition of past hits. -- kainaw™ 15:46, 18 March 2010 (UTC)

That's right. There is no data out there on individual projects' failures or profitability levels, because only the publishers know this data, and they don't release the data. But one visible indication that it's a lot more profitable today is the simple fact that you have publicly traded third-party publishers like ERTS, ATVI, TTWO, and THQI; and salaries for the top people have, I think, outpaced inflation when compared to a programmer's salary from 25 years ago. Comet Tuttle (talk) 16:29, 18 March 2010 (UTC)

It's worth noting that, while small groups (either indies, or small groups within big games companies) rarely get big hits, they do get lots of little hits. Browser flash games, mobile phone app games, etc.. A recent episode of BBC Click discussed the topic and apparently lots of games companies are starting to favour the smaller games. They are lower risk, since you can easily make 100 games and know that at least a few will be successful. If you concentrate on big games then you can only make 2 or 3, and it's entirely possible that they'll all be complete flops. --Tango (talk) 17:02, 18 March 2010 (UTC)

Although that's a great theory that I would love to see them adopt, no major game publishers are doing this currently. Comet Tuttle (talk) 17:22, 18 March 2010 (UTC)

The story said they were starting to, rather than actually doing it. I think it is happening on a small scale at the moment, and not with the biggest companies. --Tango (talk) 17:52, 18 March 2010 (UTC)

I was trying to draw a relation between the rest of the entertainment industry and video game production above. The idea of a small house putting out 100 games and hoping for a few minor hits is not abnormal. There are many straight-to-video movie companies that operate that way. Large companies can do the same. Think of Disney. Yes, they always have 2 or 3 major blockbusters in production, but they also have 20-30 straight-to-video movies like Cinderella VI, Bambi IV, or Ariel's Next Big Adventure... I'm see Square Enix growing to that level. They are already recycling old games into cheaply made (and lower priced) games. If they are successful, others will likely follow suit. -- kainaw™ 00:41, 19 March 2010 (UTC)

(I work in the games business - I'm a graphics programmer). The problem with the videogame business is twofold:

1. Customers' expectations about 'depth' of content has grown. Zork has a few hundred pages of text description of it's world - and a few thousand lines of software to run it - and that was enough back then. Something like GTA IV has every building in a large city, hundreds of music tracks, hundreds of characters, voice acting, hundreds of cars and trucks, etc. The software for a modern game engine could easily reach a half million lines of code. That's why ZORK could be written by four guys - but GTA IV required several hundred. There is a slight reversal in that trend with cellphone games and for things like Guitar Hero and Rock Band - but it's going to be short-lived.
2. Only about one in every 35 games made ever turns a profit. That makes it an incredibly risky business. The reason games like Halo-3 and GTA IV made such an ungodly amount of money was because they were a virtually guaranteed hit. Sequels of games that are popular are generally popular - so you can invest a big chunk of change into them and have high confidence that you'll make money. But a new, novel game is insanely risky.

A typical PC/Xbox-360/PS-3 game requires around 100 people for perhaps three years (although it's wildly variable both in time and staffing). That's mostly split between programmers (earning $80k to $130k maybe), artists & designers (earning probably $40k to $70k) and game testers (who often earn little more than minimum wage). There are also licensing costs for music and outsourcing costs for bulk content creation - and more licensing fees if you are making the game of a movie or TV show or something. It's quite easy to burn through a million dollars a month in the last half of the development of a big ticket game. If it fails - that's a truly massive loss.

The game I was working on for Midway when they folded had 80 artists and maybe 20 programmers with a dozen or so testers - plus managers, designers, audio guys, IT, HR, etc. We'd worked for more than 2 years on our title (a 3rd person game about high-class criminals that set in up-market locations in real-world, present-day, Chicago) - and I have to say that it looked good graphically, it had good audio, we had a famous Hollywood movie director put his personal "feel" into the thing, advising us on everything from dialog to pacing to camera angles. It worked reliably, it ran well on PC, Xbox-360 and PS-3, we had several test missions fully playable in our open-city world. Technically and artistically, it did everything we set out for it to do. But somehow, indefinably - it just wasn't much fun to play and so it was axed. Making something "fun" is tough - nobody really knows how to do that - and nobody really knows how to "fix" an un-fun game because we really don't understand why the game wasn't fun. So you can spend tens to hundreds of millions of dollars and end up with something that doesn't even end up on the store shelves - let alone turns a profit!

This means that small companies can't spend enough to get that game 'depth' without having someone with deep pockets (a "publisher") funding them and taking the risks and most of the profits. A large game company or a major publisher can make enough money off of the 1-in-35 that turn a profit to pay for the 34-in-35 that are either cancelled and never get onto the store shelves, or fail miserably once they get there. But what this means is that when you read about the ungodly amount of money something like GTA IV made, you have to understand that those profits had to pay for a ton of game development that went horribly wrong for whatever reason.

MMO's are even worse because the startup cost for setting one up is quite outrageous - vastly more than a normal game - and the risks are just as high. However, once you have them up and running, the profits are good - even when weighted against the cost of maintaining the servers, keeping the game working and continually adding content. But so many of them fail after just a few months, it's a complete crap-shoot.

Phone games (on iPhone and Android) are popular right now - and we're in that little niche in time when the public will splurge a couple of bucks on a game without it needing to be advertised to death - and the depth of content of the game can be fairly small. That allows small games companies to make them with small groups of developers and relatively little risk. Of course at $1.99 per game, they have to sell an awful lot to make money - but that's OK. Also, you can make a lot of them. A handful of guys can make an iPhone game in a year easily - so even a small company can churn out a hundred games in the time it takes to make one PC/Xbox/PS3 game - and the law of averages says that a few of them will be phenomenally successful and pay for all the rest. But this is a brief window. As these gadgets get more sophisticated - and the prospect of using cloud-computing for cellphone games takes off - the push for deeper content will once again make these games cost a lot more and we'll get all of the risk back.

Games are unlike almost any other product in that close to 100% of the cost is in the development and advertising - both of which cost the same whether you sell 1 copy or a 100 million copies. It costs less than $1 to copy a DVD-ROM and a manual and put it into a box. Most of the copies you sell will go for $20 to $40 which looks like a pretty amazingly good markup. Now WalMart and Microsoft/SONY/Nintendo take their cut (remember - game consoles sell at a loss and the hardware manufacturers take a cut of games sold for them in order to make a profit). If you're a game company who went via a publisher - they'll take a huge slice. But if you spent $1,000,000 a month for several years making it, you're going to look pretty bad if you don't sell a hundred million copies.

SteveBaker (talk) 09:06, 19 March 2010 (UTC)

Dell Optiplex to upgrade

Can anyone recommend a good Optiplex model for upgrading/building my own PC, that wouldn't cost much to buy secondhand? Basically just one with a large form factor case and a power supply that will run a decent processor and graphics card. I'm open to suggestions on other manufacturers, but was thinking of another Optiplex because I know how robust they are. This will be a kids' pc once it's finished! 89.195.206.83 (talk) 09:04, 18 March 2010 (UTC)

Intel Core

what is intel core —Preceding unsigned comment added by Kdcee (talk • contribs) 10:31, 18 March 2010 (UTC)

See Intel Core. -- Finlay McWalter • Talk 11:11, 18 March 2010 (UTC)

Also, this archived question from July, "Difference between core 2 duo and dual core". Note the important distinction between "core" (a generic term for a particular part loosely defined subset of the innards of a computer processor), and "Core™", a brand name for a specific product technology released by Intel. Nimur (talk) 15:57, 18 March 2010 (UTC)

Specific keyboard key will not function

Resolved

When i turned my computer on thiS morning, i found that the 'S' key would not function (i'm uSing the character map to copypaSta the letter). It'S not that it doeSn't function, it'S whenever i preSS it the window'S focuS iS Stolen by Something elSe. The weird part iS that every keyboard i plug in doeS thiS. The laptop built-in keyboard and even the On-Screen Keyboard do thiS. Before i Start a painfully long viruS Scan, haS anyone elSe had thiS problem? (PS: ShortcutS don't do thiS, CTRL-S workS fine)

 Buffered Input Output 12:24, 18 March 2010 (UTC)

I take it you're cutting and pasting the "S" now ? If you have a recent system checkpoint, now would be the time to do a restore. StuRat (talk) 15:30, 18 March 2010 (UTC)

It was a virus. Thanks anyway.  Buffered Input Output 15:40, 18 March 2010 (UTC)

fortran 90

I want to download fortran 90 software (free). please give me some link.Supriyochowdhury (talk) 12:29, 18 March 2010 (UTC)

GCC supports Fortran 95. —Korath (Talk) 13:15, 18 March 2010 (UTC)

GCC also supports Fortran 90. Here's the official gfortran manual, including downloadable installers for most major platforms. If you are using Linux, gfortran may already be installed. Nimur (talk) 14:23, 18 March 2010 (UTC)

[5][6] --Normansmithy (talk) 15:03, 18 March 2010 (UTC)

FrontPage site user registration

I decided to add user registration to my web site. My IP had set it up with a domain name and a prefix and a subsite with frontpage extensions installed. I now realize that the prefix site is considered the top level site where I place things like the user registration which is intended to protect access to the subsite. It also appears that I can only access the top level site using FTP and the subsite using HTTP. However, once I create the user registration I also have to protect the subsite so that only registered users can access it. Currently without a user registration on the top level site anyone can access the subsite if they know what it is named and it appears that only the IP can change the site prefix or the subsite name. Is this a correct understanding and if so how do I protect the subsite from access by non-registered users and how do registered users sign in? 71.100.11.118 (talk) 16:07, 18 March 2010 (UTC)

Ubuntu 9.10 Hibernating without consent

Every time I get the larger update which involves a restart of the computer, I have noticed that my computer tends to go to sleep after a few minutes of inactivity. I did something last time to sort this out, but recently we've had this update again, and it's started again. I have checked Power Manager, and have set everything to basically be on forever (except that 'when battery level is critically low' I have no choice but to put it on 'hibernate'). I have set the screensaver to never come on, but can only set the computer to be regarded as idle after two hours. Still, after a few minutes of inactivity, the screen goes black, and I have to press a button to get the screen back again. Particularly annoying is when I don't do that, the computer switches off. Now, when I leave a computer on, I leave it on for a reason, and don't want it to switch off when it feels like it. Can anyone tell me what the problem is and how to solve it? On a side note, I would ask this on the Ubuntu forums, but it can sometimes take days to get an answer there, and when I do, usually the writer assumes I know everything about Ubuntu, and so, although well-meaning, the answers are too technical and therefore useless to me. Any help would be appreciated. --KägeTorä - (影虎) (TALK) 17:51, 18 March 2010 (UTC)

What happened to Hotmail?

I am on a computer with Windows 7. I have had lots of problems since this software was installed, but never anything like today. I signed in to Hotmail and was doing fine until I did a search for all emails I had sent to myself with the appropriate subject line that I won't bother to explain. I clicked on one of those and then, when it was ready to delete, I did so and clicked on "Back", only to be told the web page had expired. I clicked on "Back" again and ended up in the inbox, which had nothing of value. For some odd reason I clicked on "Back" again and found myself in the other email service I had used earlier. I clicked on forward and the URL turned green (it also had a lock) and the page was completely blank. I typed "Hotmail" and even tried going there from Bing. Same result. I tried other ways of getting into Hotmail (actually, I was looking for Hotmail help) and finally succeeded in getting back to the inbox. But nothing I clicked on would take me anywhere.

It gets worse. I went back to that other email service and found I couldn't get into the inbox. I could see a list of folders but clicking on any of them just got me a bunch of white space where the list of emails should go. Fortunately, Lycos behaved normally. It has similar problems to the other email services I mentioned, but these are the result of the foolish way each one was designed. What's happening to me today is not intended by anyone.

And in one newspaper web site, I was unable to go to pages other than one in the articles with multiple pages. I'm contacting that site now.Vchimpanzee · talk · contributions · 18:03, 18 March 2010 (UTC)

Oh, and the items at the bottom of this page that I can normally click on require copy and paste.Vchimpanzee · talk · contributions · 18:07, 18 March 2010 (UTC)

I don't believe this has to do with Windows 7, but with your web browser. Which program are you using? —Akrabbim^talk 18:15, 18 March 2010 (UTC)

Internet Explorer, probably 8.Vchimpanzee · talk · contributions · 18:45, 18 March 2010 (UTC)

At last. I noticed something helpful. The yellow line that usually is saying a pop-up was blocked has been showing up all day, with a different message. I ignored it because supposedly there's nothing I can do. But I read the message and clicked like it said to and got this result when I matched up the message:

Okay, it won't let me copy and paste. Essentially it says ActiveX needs to be removed from the restricted sites list. There's something about changing security settings. I am at a library and furthermore, they tell me they can't do anything except call IT and that requires a work order. This takes time. They may not do anything today.Vchimpanzee · talk · contributions · 18:53, 18 March 2010 (UTC)

do I need to use a switch to segment, or if I have enough LAN plugs I dont need them?

I got a p.o.s. (point of sale) equipment for a small store, it came with a switch, on the back of the switch it says: typical network setup:

internet - Wireless Modem - This switch - stuff (laptop, computer, the pos equipment, etc)

But the wireless modem here already has 5 big yellow lan connectors. Do I need to use one of them for the switch for some (security) reason? Does it "segment" or do anything else with the network? Thanks. --84.153.225.240 (talk) 18:10, 18 March 2010 (UTC)

Network switches exist to give you more ports, so, no, the switch itself isn't necessary if you want to plug stuff directly into the wireless modem's ports. Do you know the model number and manufacturer of the wireless modem? That would let us give more specific advice. Comet Tuttle (talk) 18:22, 18 March 2010 (UTC)

TP-Link brand Model no. TL-SF1005D. By the way the p.o.s. is ingenico brand. So, if there are 5 free LAN connectors on the back of the wireless connection, it does NOTHING to plug one of them into this router switch and then the p.o.s. into the router switch, versus just plugging it into the wireless lan? thanks. So what's this bit about "network segments" in the routet switch article? --84.153.225.240 (talk) 18:44, 18 March 2010 (UTC)

You're getting your terminology a bit mixed up, though you had it right in the original post; you have a DSL modem (which in your case is also a router), a switch, and your other devices which need connectivity (laptop, POS, etc.) There are switches which have special features for network security (often found in managed switches) but the switch you mentioned is not managed. Adding it to the network will do nothing more than give you more ports to connect network cables.

Technical comments: The model TL-SF1005D is your switch that was provided - Comet Tuttle was asking for the wireless modem's information, but it's not really a big deal. Adding the switch would just make the network segment larger, but it's still one segment. Besides, I rarely hear the term "network segment" used outside of large / enterprise networks. Coreycubed (talk) 19:41, 18 March 2010 (UTC)

Sorry, I made a mistake, being in a rush. I've corrected "router" to "switch" as appropriate. It is the switch article whose lead includes the line "A network switch is a computer networking device that connects network segments." and then just sentence later, "The term network switch does not generally encompass unintelligent or passive network devices such as hubs and repeaters." So what does connects segments mean in a technical sense? Also, the part I've just quoted says that a switch has to do something more than a passive "hub", so what would this something be? What is the difference between the switch I've mentioned and the hub? Nothing?

The wireless modem model number is written on it as "Speedport W 503V Typ A". (It is a German modem, in line with my typing from a German IP). This wireless modem is connected to the DSL box thing. So, given that you really know everything now, what, in practical terms, is the difference between connecting the pos into the wireless modem; into the switch I mentioned and connecting that into the wireless modem; or (this is hypothetical, I don't have one), connecting it to a hub and connecting the hub to the wireless modem. What's the difference between any of these three? Thanks. 84.153.225.240 (talk) 20:13, 18 March 2010 (UTC)

Practically, there is no difference. In a technical sense, data needs to be able to travel around the segment, which in this case is your home network. (The wireless network would also be considered part of the network segment.) Let's say you had two computers. If they were connected to two different switches, those switches would in turn need to be connected to each other, or data could not pass between the two computers. Don't get caught up in the terminology and overcomplicate things! :) In lay terms, we'd just say that they needed to be networked. This is probably common sense - there are two devices that need to "talk" to each other. They have to have some way of passing information back and forth. Whether it is through the LAN ports of your Speedport or through the TP-Link switch (or both) does not matter. Your Speedport modem is actually quite the multitasker - it's acting as a modem, translating the DSL signal into a usable Internet connection, and as a router, providing NAT and DHCP addressing, and ALSO as a switch, providing four LAN ports, AND as a wireless access point (think of a wireless AP signal as a giant invisible switch, and connecting to a wireless network as walking up to that invisible switch and plugging your computer into it).

Since you're asking some hypothetical questions, here are a couple of examples of situations where it would matter how you connected it:

One switch is faster. Let's say that the TP-Link switch was capable of gigabit speeds (usually marked 10/100/1000). You'd want to connect all gigabit capable devices to that, and let the modem and switch talk at 100 megabits since that is still likely far more than your DSL connection is providing. That way, your computers can talk to each other faster, allowing them to transfer files among each other at greater speeds.

You have hubs. These are inferior to switches. You'd want to leave the hub out if possible since it is less efficient at exchanging network data than a switch is. The LAN ports in your Speedport modem are undoubtedly better than any hub would be. A hub just broadcasts packets it receives on all the others ports, so if lots of packets are being sent through the hub, you will get collisions. A switch, even an unmanaged one, can direct the flow of packets much better. The article on hubs which you linked goes into more detail, but basically a switch can handle simultaneous packet exchange while a hub cannot.

Since you also mentioned a repeater - wireless repeaters just listen for a wireless signal and rebroadcast it, effectively extending the range of wireless access points. This is why they, along with hubs, are not called switches - becuase they do not actively take a role in getting packets to their destination. Coreycubed (talk) 21:24, 18 March 2010 (UTC)

Copy/paste one partition's contents to the other partition in GParted

Because Windows was having major issues not being the first partition in the drive, I need to move the Windows partition to the front of the drive (trust me, I have explored all other avenues around this), so if I right-click in one partition and say "Copy", then click in the new NTFS partition at the front of the drive, why doesn't it allow me to paste? (The right-click and toolbar buttons are greyed out). Do I need to complete all other operations (resize, format, etc.) before I can do this?

Thanks!

110.175.208.144 (talk) 21:02, 18 March 2010 (UTC)

I don't know about using gparted for this; I've always just used dd - e.g. sudo dd if=/dev/sdc2 of=/dev/sdc1. Obviously you need to be super sure about the if and of - get them wrong and you'll overwrite the wrong partition and ruin your day. -- Finlay McWalter • Talk 21:14, 18 March 2010 (UTC)

Well, failing that, if I manually move the entire partition's content across using a file browser, will it work? Thanks! 110.175.208.144 (talk) 05:18, 19 March 2010 (UTC)

Does an electronic paper word processor exist?

There are ebook readers using electronic paper (e-paper) like the Kindle. Does there exist a device like that where you can edit text? I would really love to have that and be able to easily read outdoors in the sunlight. Too many laptops are hard to read in bright conditions. Is there a technical reason for this, maybe that blinking cursors or altering small portions of the screen are not conducive to e-paper displays? Thank you for your help. --Rajah (talk) 21:43, 18 March 2010 (UTC)

The ebook readers I've seen (a Sony and a Kindle) have displays with a pretty high latency. If memory serves, the Sony screen goes blank, then inverts, then a new screen appears (I don't remember precisely how the Kindle worked in that regard). Electronic paper#Disadvantages suggests that this is the case for the current e-ink technologies in general, and I agree with that article that the one's I've seen would be unworkable (or at least unpleasant) for a normal GUI. I'm not sure there's enough market for general high-ambient-light computing to justify making one with the current, suboptimal technology. -- Finlay McWalter • Talk 21:56, 18 March 2010 (UTC)

The iLiad allows annotation and highlighting of existing documents out of the box using an included Wacom stylus. It's Linux based, and according to the article abiword has been ported to it. The port is not really meant for editing - more for viewing rich text files, but a USB keyboard module has also been ported which allows you to plug in a USB keyboard [7]. So, yes it can be done if you are willing to do some hacking, but the end result probably won't be that smooth or easy to use.131.111.185.69 (talk) 23:09, 18 March 2010 (UTC)

Reading the site I linked to I discover they have even ported an instant messenger app and a spreadsheet program. I love Linux hackers - they are all quite mad (in a "this shouldn't be possible and certainly isn't advisable but we are going to do it anyway" sort of way). 131.111.185.69 (talk) 23:16, 18 March 2010 (UTC)

You can definitely edit text on the Kindle - I do it on mine all the time. The Kindle software offers a way to add notes to your eBooks - and that involves typing in text on the little keyboard and viewing it on the electronic paper display. You can also surf the web and enter text that way. That certainly works - so it must be possible (in principle) to do what you want. The usual problem is that machines like the Kindle are designed for ultra-low battery life - which they achieve buy using the ability of the ePaper to retain the image with the power turned completely off. The Kindle only uses power when you push a button. So you can read a dozen books over a period of weeks on one battery charge because it only takes maybe a thousand button pushes per book. However, if you were doing extensive word processing, the CPU would need to be on all the time and the display would be doing a lot of refreshing - and the battery life would probably be alarmingly short. The Kindle also has a couple of 'easter eggs' - you can play "MineSweeper" and "Gomoku" on it - which, again, requires the display to refresh 'interactively'. However, I don't know of any custom word-processors built around ePaper. SteveBaker (talk) 08:09, 19 March 2010 (UTC)

Including gpus, new and used, printers, Playstations, etc, and mainframes and services too what is the best teraflops for the money?

Say I want to do a whole lot of flops in a highly parallel way. Out of all the choices I listed in the subject line, what would give me the most FLOPS for the money. Put another way, if I had $20,000 to spend, what is the most flops I could get out of it, including on the used hardware market, and how. Just about the only thing I wouldnt consider is buying a botnet, or paying some Russian the $20000 to build me a viral botnet, for the calculations, though I suspect this would be the cheapest :) Thanks for your creative answers, and of course please feel free to include anything I didnt think of if it's better flops for the money. :) 80.187.97.187 (talk) 22:33, 18 March 2010 (UTC)

Can you clarify whether this is just fun speculation or whether you're serious about doing this? For example, there is a massive difference in the ease of implementation between a room full of blade servers and 250 Playstation 2s... if you really want to build your own parallel setup, knowing your personal software competency (or the competency of those available to you) will go a long way towards accurately shaping the answer. In short, the real question should be "what's the best speed per dollar parallel computing setup I can build if I know (insert programming language here)?" 218.25.32.210 (talk) 01:05, 19 March 2010 (UTC)

An awful lot depends on your use patterns. If you only need this thing periodically for one or two large calculations - you might be better off buying computer time from one of the large compute farm providers out there than owning your own system. There are all sorts of innovative ways to buy CPU time without owning the hardware (eg [8] or [9]). You can also sell your unused CPU time the same way. So by sticking with PC's and not buying weird hardware like Playstations, you could sell your unused CPU cycles and earn money back from your compute farm when you aren't using it. Many of the service providers sell Linux CPU hours at about half the cost of Windows CPU hours - and Linux computers are always cheaper then Windows ones because you aren't paying for the cost of the operating system - so if you are serious about this, you'll want to be running your application under Linux. If you work in a large organization, you might consider building a Stone soupercomputer - where you set yourself up to take old PC's that have been upgraded in other departments of the company and re-purpose them into a gigantic cluster. These machines are old and clunky - but the hardware is essentially free and your application is (hopefully) highly distributed - so having 100 1GHz machines that cost you nothing is better than having (say) 20 3GHz machines that cost you a thousand dollars a pop. A lot also depends on the nature of your calculations. If you can parallelize the code in such a way that it could run on the GPU instead of the CPU, you can often get a 100-fold speedup on a single PC! SteveBaker (talk) 07:59, 19 March 2010 (UTC)

Connection reset by peer.. meaning?

What does 'connection reset by peer' even mean? If random people on the internet can just reset my connection any time they want, there's a security concern right there. Hopefully it actually has a deeper meaning than that. Preferably I shouldn't have to ask this question, but the fact of the matter is that the rest of the error codes actually make a lick of sense without a lengthy explanation. ArchabacteriaNematoda (talk) 22:46, 18 March 2010 (UTC)

"peer" doesn't mean "any random node on the Internet", it means "the host at the other end of this connection". 98.226.122.10 (talk) 23:44, 18 March 2010 (UTC)

I - a different poster - never suspected this answer. You'd think if it meant "connection reset by host" it would say "connection reset by host". I guess I have high expectations. 80.187.107.143 (talk) 23:47, 18 March 2010 (UTC)

It means exactly what it says. As 98 pointed out, not just any host on the Internet can reset your connection—it has to be your peer, the particular host you're connected to. -- Coneslayer (talk) 11:21, 19 March 2010 (UTC)

A TCP connection (which is the kind that gets the "Connection reset by peer" message) is an association between 2 hosts (a host on the Internet is basically anything that has an IP address assigned to it). From the point of view of one of those hosts, the other one is "the peer". 98.226.122.10 (talk) 23:54, 18 March 2010 (UTC)

And to expand on that a little more, the "reset" refers to the RST bit in the TCP header. "Connection reset by peer" means that a packet was received in which the RST bit was 1, indicating that the peer (i.e. the other host that you were connected to) believes the connection is no longer valid. For some random third party to cause this to happen, they would have to be able to forge the IP address and TCP sequence number, which used to be surprisingly easy to do, but defenses against that are fairly good now. Your ISP, however, can still do it to you, and don't think they won't. (I believe Comcast has used forged resets to slow down bittorrent users...) 98.226.122.10 (talk) 00:00, 19 March 2010 (UTC)

"used to"? Did Comcast stop attacking torrent use with fake resets? -- kainaw™ 00:35, 19 March 2010 (UTC)

Yes. The FCC ordered them in August 2008 to stop before the end of the year, and they did.--Chmod 777 (talk) 01:10, 19 March 2010 (UTC)

The term can be traced back to the OSI Model (although our article doesn't use the term - instead see here). Each layer in the model must (and can only) communicate with its peer on the other side of a connection. --LarryMac | Talk 00:02, 19 March 2010 (UTC)

Formatting

Does frequently formatting our system to install the OS in the same drive slows down our system????