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November 26

Java web start

Getting this pop-up error "microsoft jscript compilation error" "syntax error" - it seems to be associated with .jnlp files. Googling shows similar problems going back a few years. This appears to be a new version of the bug. eg I think I've fixed it by selecting 'direct connection' rather than 'use browser settings' in the java console>>network settings .. though to be honest I don't really know what I'm doing. (XP, chrome, java 1.6.22) Consistently happens with any web start, applets so far appear ok.

Can anyone expand on what's going on here.. I don't really know if it's a bug I should report to sun/oracle, or to microsoft. Thanks.213.249.248.176 (talk) 00:22, 26 November 2010 (UTC)[reply]

Where can I find a smartphone app for ChatRoulette?

Pretty often, popular web services port themselves to the mobile realm by releasing apps meant for smartphones.

Where can I find phone apps for ChatRoulette (or Omegle, or any other competitor of ChatRoulette?)

If those apps don't exist, why the heck not? You'd think their services are popular enough to make mobile apps out of, right? --70.254.193.68 (talk) 07:49, 26 November 2010 (UTC)[reply]

Considering what the ChatRoulette article you linked to says (which somewhat concurs with what I expected) I'm sceptical Apple would approve of a ChatRoulette app. Not sure about Android though. Nil Einne (talk) 11:20, 26 November 2010 (UTC)[reply]
Well a simple websearch for the most obvious term 'chatroulette app' easily found [1] and other things confirming my belief a chatroulette like app isn't going to last long with Apple. Nil Einne (talk) 11:22, 26 November 2010 (UTC)[reply]
In fact it's even specifically banned in the guidelines now [2] Nil Einne (talk) 12:01, 26 November 2010 (UTC)[reply]

Mac Wildcard Character

Hello, anyone know how to perfom a *.* search on MAc OS X? Ideally without resorting to the Terminal, but needs must. Thanks. FreeMorpheme (talk) 11:13, 26 November 2010 (UTC)[reply]

What do you want to search? List all files whose name contains a period ("ls *.*")? List all files in a directory ("ls")? List all files in a directory and its subdirectories ("find -print")? Search something inside files ("grep ..." for text files)? Something else? Captain Hindsight (talk) 11:27, 26 November 2010 (UTC)[reply]


I would like to list all of the files and folders in a folder in one window. *.* works on the PC as it shows everything with a filename and an extension. FreeMorpheme (talk) 13:46, 27 November 2010 (UTC)[reply]

Just view a folder's contents as a list? At the top of the folder's window, on the left there should be icons for different views - depending on what OS you are running. These are 'icon view', 'list view', 'column view' and 'cover flow'. Or you can choose View>as list from the Finder menu bar at the very top of your screen. Does the list view not do what you want?  pablo 15:09, 27 November 2010
Your confusion lies in the fact that (under DOS) the extension was seen as a necessary part of the filename: so to list all files with all names and all extensions, you would type "*.*". Under Unix, including OS X, the dot is just another character (in other words, the idea of a "filename extension" is an interpretation humans put on the filesystem, not something built into it). So under Unix, searching for "*.*" means searching for all files with a dot in their names. But the answer to your question is a simple "*". Marnanel (talk) 16:17, 27 November 2010 (UTC)[reply]
Well yes, but the OP states that they would prefer not use Terminal. All the files and folders within a particular folder should be visible in that folder's window in the Finder. pablo 21:48, 28 November 2010 (UTC)[reply]
I see I wasn;t quite clear enough, apologies - I need to see all of the files and folders, but all of the files in the subfolders also. So if I have a folder with three subfolders each containing 20 files, I want to perform a search on the top level folder which will reveal three folders and 60 files, all in one window 195.60.20.81 (talk) 11:34, 29 November 2010 (UTC)[reply]

STV iPlayer

I have just watched a fascinating series of programmes on the above and wonder if there is anyway I can download them to a DVD on my AppleMac laptop. Any ideas out there please? Thanks in anticipation.--85.211.132.205 (talk) 12:24, 26 November 2010 (UTC)[reply]

It may be helpful if you specify (perhaps a link) to what you mean. I don't live in the UK but AFAIK iPlayer is a exclusively BBC thing, probably trademarked. 'STV iplayer' also doesn't find any iPlayer for STV. Do you perhaps mean the STV player [3], BBC iPlayer or even the ITV Player [4]? Nil Einne (talk) 06:01, 27 November 2010 (UTC)[reply]

I mean STV Player, that is Scottish Television.--85.211.227.216 (talk) 08:06, 27 November 2010 (UTC)[reply]

Well in that case official it's not supported [5]. Unofficially if you can watch it there's obviously some way to record it. Worst case scenario you could probably use some sort of screen capture program or even a camera recording your monitor. However I suspect it's not necessary to go this far although using Mac OS X probably doesn't help. There's very little discussion of recording/downloading STV player I could find (much more of ITV of course). [6] is one of the only ones and it doesn't sound hopeful although it's somewhat old (while not Mac OS X per se, it's discussing open source tools which would could probably made to work with Mac OS X).
In Windows there are plenty of commercial and some free programs for this sort of thing. I normally use Orbit Downloader [7] which works for most things I do but I tried it with the STV news website (don't live in Scotland or even the UK nor do I have a proxy so can't try on the player website) which is linked from the player website. And it doesn't work (catches the URLs but downloads seem to fail) although I didn't really try that hard. I read some suggestions from [8] and other players that Replay Media Catcher [9] may work. It didn't work at all (didn't catch anything even Youtube) on one of my Windows installs I guess because it didn't manage to hook in to the network stack properly (from what I've read I think it does something like this) because of the odd stuff I had installed. On another Windows install it seemed to work for downloading from news.stv.tv (also youtube of course).
Once you have a stream, converting it for a DVD-video (if that's what you want) is relatively trivial.
I would note your message is somewhat ambigious on what you want to do with the content. Downloading it to keep indefinitely and watch as often as and whenever you want is likely of questionable legality (the same as recording a program off air) although as long as you can still watch the program online from where you live it perhaps doesn't make a difference when you downloaded it. But if you do want to keep it, you may want to see whether the documentaries are available in commercial DVD or other formats where it's intended for you to keep it (e.g. legal video download services like iTunes).
Nil Einne (talk) 14:11, 27 November 2010 (UTC)[reply]
Thanks all, have just noticed that STV player says it is not possible to download the programme; shame since they are only available on line for 30 days.85.211.136.83 (talk) 08:23, 28 November 2010 (UTC)[reply]

scanmem for Mac

Is there a program like similar to the linux scanmem utility available for Mac OS X (specifically 10.6)? If one doesn't specifically exist, could the linux tool be adapted for Macs? Horselover Frost (talk · edits) 13:21, 26 November 2010 (UTC)[reply]

Although the commonplace Unix method of viewing another process' memory via /proc isn't available on OS-X, that doesn't mean there isn't another mechanism to do so (otherwise things like debuggers and profilers couldn't work). On OS-X one can access memory piecemeal with ptrace or wholesale with mach_vm_read. The latter is substantively the same as opening a process' memory by calling read(2) on the relevant /proc/PID or /proc/PID/mem entry. So it surely could be written. Note, however, that (I think uniquely among Unix-like OSes) OS-X has a special option to ptrace, PT_DENY_ATTACH which allows a process to prevent itself from being ptraced, dtraced, and I think having its VM manipulated with the Mach calls - so memory of a process like iTunes that uses this mechanism won't (readily) be accessible (but that mechanism can be circumvented, I read). -- Finlay McWalter ☻ Talk 14:04, 26 November 2010 (UTC)[reply]

Google

Resolved

Is there a limit to how many google email accounts you are allowed to have? 82.44.55.25 (talk) 14:36, 26 November 2010 (UTC)[reply]

There seems to be some legalese about it here, however ,I believe that you will probably get the full terms in that box you have to tick to say that you have read the Ts&Cs to set up your initial account. The content I've linked to suggests that the creation of multiple accounts to do naughty accounts is a bad thing, but does not appear to mention anything about the innocent use of multiple accounts. Not quite a complete answer to your question I'm afraid. Darigan (talk) 14:42, 26 November 2010 (UTC)[reply]
edit - better link - seems to be ok to use multiple accounts as long as you don't violate the terms of use Darigan (talk) 14:45, 26 November 2010 (UTC)re[reply]
Thanks 82.44.55.25 (talk) 20:18, 26 November 2010 (UTC)[reply]
Although I would note Google does require some sort of verification in some countries (well I think the OP knows that). SMS to mobile phone is one in some. I'm pretty sure there's a limit to the number of accounts you can register using one number as verification (think I've read people complaining before) and I'm not sure how easy it would be to convince them to let you around the limit even if you've been doing nothing untoward with your accounts. Nil Einne (talk) 05:06, 27 November 2010 (UTC)[reply]
Semi supports that idea [10]. I realised I forgot to note there's of course nothing to stop you using some other number of some other method where available. Nil Einne (talk) 05:53, 27 November 2010 (UTC)[reply]

Microsoft Timershot

Microsoft have a "power toy" called Timershot for Windows XP, but it doesn't work on Vista. Is there any way to make it work on Vista, or any other free alternatives? Please don't tell me to google it, I already have and all I have found is pages and pages of other people asking the same question and being told to google it. —Preceding unsigned comment added by 86.192.175.138 (talk) 15:36, 26 November 2010 (UTC)[reply]

I've added a new section for you, to make your question stand out from the previous one CS Miller (talk) 16:09, 26 November 2010 (UTC)[reply]
Well a simple search for 'windows webcam software' finds [11] as the first result and [12] as the 4th. Really there's probably so much software I suggest you just choose one at random which seems to do what you want and try it. If it doesn't work the way you expect uninstall or rollback the install and use something else. I myself when looking for something of the sort a few months ago (not a timershot replacement as I never used timershot) found something at random and it seemed fine although ironically I can't find it again now Nil Einne (talk) 04:44, 27 November 2010 (UTC)[reply]
Found it via 'windows 7 webcam time lapse photo' at [13]. Avacam. Nil Einne (talk) 05:03, 27 November 2010 (UTC)[reply]


November 27

.tar.gz is a compressed file in a compressed file?

If so, why? ----Seans Potato Business 00:06, 27 November 2010 (UTC)[reply]

The .tar on its own usually does not use compression. .tar#Compression_and_naming explains in detail 82.44.55.25 (talk) 00:21, 27 November 2010 (UTC)[reply]
(ec) tar doesn't compress files, it just archives them, i.e. concatenates them together along with some metadata like file names, modification times, and so on. -- BenRG (talk) 00:22, 27 November 2010 (UTC)[reply]
".gz" files are GZIP files - see http://www.gzip.org/ Exxolon (talk) 04:17, 27 November 2010 (UTC)[reply]
Indeed, tar on its own can produce a significantly larger file than the original, because it was designed for writing to tape (that's what the t stands for) and writes in multiples of 512 bytes at a time. However, since disks these days are written in larger blocks than that, the actual disk space consumed by an non-compressed tar file is likely to be no more than that of the constituent files. --Anonymous, 06:10 UTC, November 27, 2010.
The other important thing is that a .gz is a single compressed file, unlike a .zip file, which compresses many files. Paul (Stansifer) 21:19, 27 November 2010 (UTC)[reply]
Unix philosophy ¦ Reisio (talk) 16:26, 27 November 2010 (UTC)[reply]
Ceci n'est pas... Marnanel (talk) 16:36, 27 November 2010 (UTC)[reply]
O tempora… ¦ Reisio (talk) 02:18, 28 November 2010 (UTC)[reply]
Briefly, in unix philsophy the goal is to break functions down so that each logical step has it's own program. This way unix commands can be combined in ways the original programmers never thought of.
In this case zipping a file has two steps, putting all the files into one big file, then compressing the big file. The "tar" file is the one big file, and when it's compressed the ".gz" is added. (Sometimes the two extensions are shortened to .tgz so as not to freak out certain older filesystems.) APL (talk) 21:53, 28 November 2010 (UTC)[reply]

darknet search engine

i remember reading this article on search the deepnet and this article dwelt on how advertisers and companies were using it to spy on people and discover habits. one thing i remeber of one these sites is that they offered to delete the info in the stuff uve done if u give them ur email id . does any one know any thing about the site.Metallicmania (talk) 16:25, 27 November 2010 (UTC)[reply]

Have a look at Ixquick and Criticism_of_Google#Privacy.Smallman12q (talk) 22:08, 27 November 2010 (UTC)[reply]

Copy and paste problem with emails that are not plain text--solved!

Referring back to this question, I have been having a problem with text that included symbols and other items that I copied and pasted into emails that were not plain text, ever since the introduction of Internet Explorer 8. Today, the text copied just fine.

I know of one thing I did in recent weeks. Java has been nagging me for months to do an update. I was always scared to add new software because it might cause problems, but I decided to go ahead this week.

One other thing is different. For some reason spaces between paragraphs didn't copy in the past. They did today.

Something else is happening and I'd like to know how to reverse it. On one of those sites with the symbols and other stuff, I no longer see "[FONT="San Serif"]text[/FONT] or [COLOR="Blue]Text[/COLOR]. I can only see what was done, not how. But if I don't know the name of the color, or the font or its size, I don't know how to do this. I want to be able to see these items again.Vchimpanzee · talk · contributions · 17:19, 27 November 2010 (UTC)[reply]

œ

æ is included with the accented characters in Unicode, so why isn't œ? Between accented "o" characters and accented "u" characters, there's even a space used for the division sign. Why did they put that there instead of œ? --75.33.217.61 (talk) 19:01, 27 November 2010 (UTC)[reply]

To clarify your question: are you asking why the specific code-points for æ and œ are not near each other in the Basic Multilingual Plane? I think the concise answer is "because" - and the elaborate answer is that there are literally tens of thousands of code-points for various glyphs; the BMP attempts to place the "most common" glyphs in one single plane (a grouping of 65536 code-points); and attempts to sub-organize these as contiguous blocks of "related" code-points. Æ falls into the C1 Controls and Latin-1 Supplement block and Œ falls into the Latin Extended-A. So, at some point in history (probably before Unicode was even formulated), some engineer or linguist decided that Æ was a "supplementary" Latin character and Œ was an "extended" Latin character. Why? For the same reason that dž is assigned to code-point U+01C6 instead of being placed near the regular letter "d." There's no possible way to make a linear "alphabetical listing" of all possible code-points, while preserving all possible similarities between all possible glyphs. Unicode is not intended to place "similar-looking" glyphs near each-other. It's intended to provide a consistent encoding, representation and handling of character-points that represent the most common forms of human writing. It inherits some legacy code-point organization from ASCII and earlier ISO standards, too; and those were not as well-thought-out as Unicode. For further reading, see ISO/IEC 8859-1 - which is the specific legacy-encoding that is superseded by BMP U+0000 to U+00FF. Specifically: "Languages commonly supported with nearly complete coverage of their alphabet - French – missing the ligatures Œ and œ as well as the very rare Ÿ (they are generally replaced by digraphs OE and oe, and Y without the diaeresis) (Windows-1252 and ISO-8859-15 do contain these))." In other words, in a previous era, somebody decided that Œ was unneeded. Nimur (talk) 20:18, 27 November 2010 (UTC)[reply]
The short version is that the first 256 code points of Unicode were copied from ISO/IEC 8859-1 (Latin-1), which contains æ but not œ. I'm less sure why it was omitted from Latin-1. There are some odd inclusions/omissions in Latin-1 and, for that matter, in ASCII. The placement of × and ÷ in Latin-1 is interesting and makes me wonder if they were a last-minute substitution. -- BenRG (talk) 21:11, 27 November 2010 (UTC)[reply]
8859-1 was intended to support western European languages and it was decided that œ wasn't needed for any of them. What I've read (but I don't know where, to cite it) as that at that time the French considered that "coeur" and "cœur" were just typographical variants of each other, like "fit" and "fit" in English, so there was no need to take up a valuable code point for œ. Later they changed their minds and the result is ISO 8859-15, which was meant to replace 8859-1, dropping such handy characters as ÷ and ½ in order to add œ and a few others. Then Unicode, of course, included everything. --Anonymous, 04:00 UTC, November 29, 2010.

Polling (Mouse)

I have purchased a gaming mouse which has an option named "polling". The configuration of this feature is: 100 T/S, 500 T/S and 1000 T/S. However, I have set it to default state, 500 T/S. I have no idea about "polling" feature. What is it for and what function does it do? What if I increase the number to 1000 T/S? thanks--180.234.51.95 (talk) 21:40, 27 November 2010 (UTC)[reply]

It it is the Times / Second the mouse updates its position. So higher should be better with regards to lag, but I guess there's some kind of a trade-off since it's customizable. --85.76.87.120 (talk) 22:03, 27 November 2010 (UTC)[reply]
See Polling (computer science). It would probably increase the accuracy of the mouse...though the default windows setting is 125 T/S. Increasing past 500 won't do much unless you're in gaming/art or other related programs where a pixel might make a difference. Past 500 would be wasting cpu cycles.Smallman12q (talk) 22:04, 27 November 2010 (UTC)[reply]


November 28

Saving a Flash Picture

Is it possible to save a picture on a website that appears as a flash? If so how? Whenever I right-click on the picture it just gives a sub-menu that has play or loop options, how can I save that picture as a bitmap or jpg or in paint when those options aren't even available in the save as dropdown box? —Preceding unsigned comment added by 71.137.254.113 (talk) 01:01, 28 November 2010 (UTC)[reply]

Take a screenshot. --Mr.98 (talk) 02:08, 28 November 2010 (UTC)[reply]
Using Firefox with the Page Info or CacheViewer add-ons works for me. 92.15.14.132 (talk) 23:28, 28 November 2010 (UTC)[reply]

"content blocked" IE message

Hi,

In the following Internet Explorer message, does anyone know what "other content" might refer to?

"Pop-up blocked. Also, to help protect your security, Internet Exporer blocked other content from this site."

(I understand the part about "pop-up blocked". I'm not asking for an explanation of that.) 86.184.31.210 (talk) 02:39, 28 November 2010 (UTC).[reply]

Probably the "other content" being Active X controls. Although it depends on your security settings, you may want to check out what they are by going through Tools>>> Internet Options>>> Security tab. 24.189.87.160 (talk) 03:25, 28 November 2010 (UTC)[reply]

Fibre Optic Strands

Hi,

How many fibre optic strands connect Australia to the United States? Is there a diagram somewhere which shows all the international fibre optic links?

Thanks, --58.175.32.62 (talk) 10:51, 28 November 2010 (UTC)[reply]

Here List of international submarine communications cables? Not a diagram unfortunately - but a huuuuge list. Do remember being in a pub in Cornwall as a child (for a family meal) and there was a map showing all the comms-cables for the atlantic which fascinated my easily fascinated mind. ny156uk (talk) 14:54, 28 November 2010 (UTC)[reply]

Modern images of the undersea cable network are here and here, although they're not terribly easy to get detailed info from. Ny156uk may have visited Widemouth Bay or Porthcurnow, both of which have cable landing points. A map of the 1901 telegraph cable network is here. -- Finlay McWalter ☻ Talk 17:01, 28 November 2010 (UTC)[reply]
Actually that telegeography.com site I linked to above has a more detailed version as well, which is very informative: [14] -- Finlay McWalter ☻ Talk 17:22, 28 November 2010 (UTC)[reply]
Also [15] although not as detailed and from 2009 Nil Einne (talk) 20:03, 28 November 2010 (UTC)[reply]
[16] may be interesting Nil Einne (talk) 18:28, 28 November 2010 (UTC)[reply]

(DOM)(HTML5)(JavaScript) Checking the size of a canvass element

The origin of the canvas element is on its upper left side. However, in mathematics, the origin is usually placed on the lower left side (1st quadrant). Now I have several canvas elements of various sizes. I wan to write a JavaScript function that maps the math coordinate system to the screen coordinate system. The first thing it needs to know is the height of the canvas it's working on in pixels. Certainly I can store the canvas dimensions in an object whenever I create a piece of canvas. If I am not doing this, can I get the size of a canvas from anywhere?

I tried document.getElementsByTagName('the id of my canvas'). It doesn't work. -- Toytoy (talk) 11:57, 28 November 2010 (UTC)[reply]

The HTML canvas object already knows its own dimensions, and these are available in the JavaScript DOM via attributes:
<input type="button" value="Click Here" onClick="dosize();" />
<br />
<canvas id="mycanvas" style="border:2px dashed;" />
<script>
  function dosize(){
    var c = document.getElementById("mycanvas");
    alert("width is " + c.height + 
          "\nheight is " + c.width);
}
</script>
-- Finlay McWalter ☻ Talk 13:56, 28 November 2010 (UTC)[reply]
Note for your future exploits that getElementsByTagName() wants a tag name like "div" or "table", not the ID of a particular element. The ID is supposed to be unique, so you'll never have getElementsById(). --Sean 17:02, 29 November 2010 (UTC)[reply]

Message Rules

Hello. I implemented two message rules for the same sender:

  1. Move email to "some" folder if sender's address is "john.doe@gmail.com"
  2. Forward email to "john.smith@hotmail.com" if sender's address is "john.doe@gmail.com"

My email applies the first rule but not the second. How can I fix this? How can I merge these rules if I use Hotmail? Thanks in advance. --Mayfare (talk) 17:53, 28 November 2010 (UTC)[reply]

Both rules are trying operate on the same message when the message arrives in the inbox. If rule 1 runs first, then rule 2 won't see the message in the inbox because it would have been moved to another folder. Try switching the order of the rules. Astronaut (talk) 20:59, 28 November 2010 (UTC)[reply]

Hotmail moves emails before forwarding. I can't reorder the rules. --Mayfare (talk) 22:36, 28 November 2010 (UTC)[reply]

Are you using an email client, and if so, which one? Or is this purely via Hotmail? pablo 00:29, 29 November 2010 (UTC)[reply]

I check my email in Windows Live Mail but my message rules are controlled from Hotmail on the web. If I configure my rules in this manner, does it matter? --Mayfare (talk) 03:34, 29 November 2010 (UTC)[reply]

Sorry, I don't use Hotmail, and I don't know how rules are set up there; I was thinking more of rules which you can define locally and apply to email (even Hotmail email) on receipt, using programmes such as Outlook, Entourage etc. pablo 11:46, 29 November 2010 (UTC)[reply]

What's wrong with my laptop?

Hello. A few days ago, my laptop suffered a fall which resulted in its battery and bottom cover falling off. Before putting them back into place, I checked the hardware inside and could see no apparent physical damage.

Since then, my laptop has acquired the stupid habit of spontaneously resetting itself without warning. I have accessed files on all sectors of my hard disks without any problem, so I suspect my laptop's problems are caused by possible damage to its fan. Nevertheless, it's never especially hot or even hot at all when it resets itself, so that seems to eliminate the theory of overheating. I'm at a loss to explain what the problem is.

What is the problem with my laptop then? I can provide further details if needed, just ask. Thank you a lot to anyone who can help identify the root of the problem.

This does sound like a failing hard drive, though. Even if you can access all of the files, the hard drive could still be damaged and causing the computer to restart. Any blue screen errors? Have you tried safe mode? Logan Talk Contributions 18:44, 28 November 2010 (UTC)[reply]
I've tried safe mode, but it still restarted. I got no blue screen errors. Let me make a list of what seem like important details:
  • I've run the Disk Defragmenter on unit C:\ with no problems at all.
  • One of the times, Windows was unable to boot and a diagnosis screen appeared. It restored the computer to a previous restore point and, since then, the frequency of restarts has greatly diminished.
  • I've run a registry cleaner (Glary Registry Repair) with no problems at all.
  • If the computer restarts and I later try to restore the file I was using, it often restarts again.
  • The laptop has become unable to "wake" from hibernation mode.
  • The computer worked perfectly fine the first time I used it after the fall. It only started bugging later on. Leptictidium (mt) 18:50, 28 November 2010 (UTC)[reply]
I experienced a similar issue with an old laptop many years ago. The RAM chips had come loose and taking them out and then putting them back properly fixed the problem. It's worth a try, especially considering the hibernation issue (doing that might void the warranty though, so if it's covered by any free repair schemes or warranties go to them first) 82.44.55.25 (talk) 20:07, 28 November 2010 (UTC)[reply]
Almost all laptops do not like being dropped. You seem to have been lucky in that it seems to be mostly still working. However, perhaps you have cracked one of the circuit boards, dislodged memory cards or loosened one of the connectors inside, and under some circumstances, perhaps when it warms up, contact is lost with unpredictable results. Check your insurance and warranty. Alternatively, take it apart -very carefully- noting where everything came from, and see if there is anything obviously loose. I goes without saying, you should back up your stuff before any repair attempt. Astronaut (talk) 21:20, 28 November 2010 (UTC)[reply]
You could also run it using a live USB that would at least discard the hard drive issues. If only the hardware is damaged, it will be easy to repair by yourself (just substitute it). Since the laptop is still running also try to make a backup of all your data before you do anything. Quest09 (talk) 09:36, 29 November 2010 (UTC)[reply]

OpenVPN remote issues

Resolved

Hello! I set up a simple point-to-point VPN on my home network with OpenVPN. When I connect from my LAN, it works fine, but when I connect via my router's IP, it seems to fail; even though it claims it completed the initiation, I can't ping the server. Below is the output (removed some digits of my IP). Note that the only thing I've changed between both tests is the "remote" directive in the client's conf file, from the local IP to the router's remote IP. At first, I suspected it's a problem with the router (Linksys WRT54G, latest firmware, and the VPN port is open and set to forward to the server), but I don't understand why it would forward local VPN traffic but not remote traffic.

Thank you for any advice or suggestions!--el Aprel (facta-facienda) 19:44, 28 November 2010 (UTC)[reply]

Silly me. It turns out my problem was that I was testing the remote connection from my LAN, which must have been too much for my router or created buggy IP reference. Getting off my couch an accessing the VPN from a remote network works fine.--el Aprel (facta-facienda) 03:00, 30 November 2010 (UTC)[reply]

November 29

Eight Nehalems in 2U: Electrical & Thermal Considerations

   I have been wondering; is it electrically and thermally possible to put eight Intel Xeon 7500 Series processors and a terabyte of RAM into a single 2U server? I mean a single system server, whether it has eight sockets on a singe baseboard or it consists of two quad-socket boards glued together. Amax's ServMax X1401 has half of that (four Nehalems and 512GB of RAM) in half the space. Rocketshiporion♫ 04:04, 29 November 2010 (UTC)[reply]

Add-ons and other issues

If I uninstall an add-on on the beta version of Firefox 4.b7 due to incompatibility issues, will it also be automatically uninstalled in the 3.6.12 version? 24.189.87.160 (talk) 03:59, 29 November 2010 (UTC)[reply]

Oh yeah, and while switching in between both versions, my reload button has mysteriously disappeared in 3.6.12. 24.189.87.160 (talk) 05:56, 29 November 2010 (UTC) Nevermind that, it just got relocated, and I couldn't tell it apart from my blue background. 24.189.87.160 (talk) 07:52, 29 November 2010 (UTC)[reply]

Are you using the same profile for both versions? If so, then probably yes. However I would have thought as a beta version Firefox 4 should keep its profile separate from your current install version, but it might not. In the future you might like to check out FirefoxPortable which can install alongside any existing Firefox you have on your computer and won't change or interfere with any of your current settings. 82.44.55.25 (talk) 10:34, 29 November 2010 (UTC)[reply]
Thanks for the link to portable Firefox. Is there any way I can set up separate profiles for each version of Firefox I have running? 24.189.87.160 (talk) 10:58, 29 November 2010 (UTC)[reply]

Questions about wireless carrier technologies (GSM, CDMA...)

Until recently, it used to be that, there were 2 different technologies used for Canada's wireless "Big 3" networks: GSM used by Rogers/Fido and CDMA used by Bell and Telus.

Ever since 3G (and 3.5G 3G+ and whatever other marketing gimmicks they use) I cant keep track of all the new ones.

Is the HSPA (including HSDPA/HSUPA/HSPA+) 3G network used by the Big 3 companies compatible with each other in the sense that unlocked HSPA phones can work on all 3 networks? What about "travelling on other networks" (basically domestic roaming) does that work seemlessly if you have one network's phone and you are in an area only covered by the other network's 3G?

Another question... if you buy a new 3G HSPA phone from Rogers/Fido, would it work on their 2G (GSM) network if you are in an area with 2G coverage only?

Same question for Bell and Telus, are the new 3G HSPA phones capable of using the old CDMA network?

One last question, the two new independent companies, WIND Mobile and Mobilicity, are they both on UMTS networks? Do their phones work with 3G HSPA networks or 2G (GSM or CDMA) networks?

Answer as many of my these as you can please... i'm totally baffled by all of this and whatever u can clarify would be of great help Roberto75780 (talk) 08:22, 29 November 2010 (UTC)[reply]

First, this may be inaccurate (I live in Australia) but phones that are not too old (like 2 years) should still have GMS or CDMA capabilities (depending on the carrier). General Rommel (talk) 09:11, 29 November 2010 (UTC)[reply]
I work for a wireless carrier here in the U.S. So, although I'm not an expert on the situation there in Canada, I can say that interoperability depends on the phone. The phone has to support the access method (CDMA or GSM) and the frequency used by that carrier. I understand that Bell and Telus use CDMA for 2G and HSPA (which uses GSM) for 3G. I also understand that they use the same frequencies. So, Bell and Telus phones should work on both networks for both data and voice. Their customer-service reps may not help you move your phone between their networks, but you can always do this manually if they refuse by reprogramming your phone on your own. There's generally a code you enter on the phone to enter the programming screen, from where you can enter the SID (system ID) and the MIN manually.
As for Fido, it uses GSM for everything (both 2G and 3G), right? In general, GSM phones are not compatible with CDMA networks and vice-versa. There are some phones that operate on both (like the BlackBerry Storm 2), but they are rare. Here in the U.S., there are two GSM carriers (T-Mobile and AT&T). Although they both use GSM and HSPA, they use different frequencies. Some GSM phones support both frequencies, so they work with both T-Mobile and AT&T. But, from what I understand Telus and Bell in Canada use the same frequencies for both CDMA and GSM, so they are compatible. But Fido does not appear to be compatible with those carriers.
As for WIND Mobile and Mobilicity, the "List of Canadian mobile phone companies" entry says that they use HSPA. HSPA uses UMTS.--Best Dog Ever (talk) 09:39, 29 November 2010 (UTC)[reply]
The above reply is correct but there are a few things worth adding. There are plenty of handsets that work between CDMA and GSM for voice (known as "world phones") and among them are most blackberries, and some new Android phones. However, the frequency differences of the 3G technology are where you will find a lot of inconsistencies, and while you may get voice functionality your data speed will be limited to 2g (or 1x or edge or whatever you want to call it.) If you are just worried about voice capabilities, verifying that the phone is CDMA and GSM capable is sufficient (although to actually move between carriers usually requires "unlocking" the handset.) So, while phone shopping be sure to check the specs for the base technology (gsm/cdma/both) and 3g technology (hspa, umts, and frequencies.) If you are set on having the widest amount of compatibility, a Blackberry is probably the best choice. --144.191.148.3 (talk) 16:20, 30 November 2010 (UTC)[reply]

Python as a calculator

... generates these results: 

>>> 4 * 0.18
0.71999999999999997
>>> 4 * 0.08
0.32000000000000001

Why not 0.72 or 0.32? Is that the same in other programming languages? Quest09 (talk) 09:30, 29 November 2010 (UTC)[reply]

See IEEE floating point, which is how most computers represent numbers with fractions.
Basically 0.72 is represented as
1*1/2 + 0*1/4 + 1*1/8 + 1*1/16 + 0*1/32 + 1*1/64 ... or 0.101101...
Likewise, in decimal notation 1/3 can not be exactly represented; for those used to the trinary number system where decimal 1/3 would be represented as trinary 0.1 they might be suprised that our decimal number system can't represent it exactly.
The only reason we use the decimal system is that we have 10 digits on our hands. —Preceding unsigned comment added by Csmiller (talk • contribs) 10:06, 29 November 2010 (UTC)[reply]
How do proper calculators avoid giving these binary-biased results? 213.122.68.179 (talk) 13:18, 29 November 2010 (UTC)[reply]
Arbitrary-precision arithmetic. You can do this in Python (and other languages) too:
              from decimal import Decimal
              Decimal('4') * Decimal('0.18')
              # gives: Decimal('0.72')

              # but if we try to express that Decimal as a float:
              float(Decimal('0.72'))
              # gives 0.71999999999999997, for the reasons noted above.
-- Finlay McWalter ☻ Talk 13:31, 29 November 2010 (UTC)[reply]
You seem to be talking about decimal floating point, which is not the same as arbitrary-precision arithmetic. That's what Python's decimal module implements, and I think it's what most pocket calculators use. -- BenRG (talk) 17:22, 29 November 2010 (UTC)[reply]
A further point is that since a calculator stores only a few numerical values and has limited display room, it's easy to design it to store more digits than it displays. So when it multiplies 4×0.18, it might really be calculating 0.71999999999999997 internally and just rounding it to 0.7200000000 for display. In fact I don't think this technique is widely used, but it's possible. You could find out by subtracting numbers whose valuess are close together, like 1/3−0.333333333. --Anonymous, 03:17 UTC, December 1, 2010.
I should note that the "problem" with floating point isn't because it's binary. As Csmiller notes, there's nothing special (especially good or especially bad) about decimal, and you get rounding errors and repeating representations regardless of how many fingers you have. The space used to store, and the time taken to calculate, floating point ops are essentially fixed (they're not related to the numbers in question) which means it's a handy scheme for applications where performance is important, and exact representation and small errors aren't (like controlling robot arms or 3D graphics). Arbitrary-precision arithmetic, which represents numbers as a string of digits (it's how you were taught in school) uses storage and takes time in proportion to the string-sizes of the numbers (see computational complexity of mathematical operations) - it's good when you need accurate representation (e.g. for financial applications) and don't care so much about speed or memory use. But arbitrary precision has issues with irrational numbers (it has to truncate them at some arbitrary position, otherwise it'd never finish). Note incidentally that when the Arbitrary-precision arithmetic article says arbitraries are slow because they have to be "implemented in software", that's abject nonsense: they don't have to be implemented in software (it's a lot more work to do in hardware than fp, but it's quite tractable) and their speed issue is a fundamental result of how they work. -- Finlay McWalter ☻ Talk 14:02, 29 November 2010 (UTC)[reply]
What normally happens is the programmer knows of these precision problems, and rounds any floating point number to a few decimal places before reporting them to the user, thus avoiding the large number of decimal places. CS Miller (talk) 14:48, 29 November 2010 (UTC)[reply]
The problem that the original poster is talking about is a side effect of using binary instead of decimal. 4 * 0.18 is 0.72 exactly in decimal floating-point. That's why using the decimal module fixes the problem. Decimal floating-point arithmetic is routinely used in the financial industry for this reason. Also, "arbitraries are slow because they have to be implemented in software" isn't abject nonsense; it's true that on 99%+ of computers out there, binary floating point has special hardware support while alternatives must be implemented in software. Sure, arbitrary precision requires extra work in any case, but there's a big slowdown up-front just from the software simulation.
"Arbitrary-precision arithmetic" makes me think of computable real arithmetic, which can retain full precision even with irrational or transcendental numbers. I don't know if there's a computable real package available for Python, though. -- BenRG (talk) 17:22, 29 November 2010 (UTC)[reply]

An even easier way of circumventing this issue is converting floating point numbers into a string. Without importing anything, simply try: 

 str(4*0.18)

. —Preceding unsigned comment added by Trustinchaos (talk • contribs) 17:00, 29 November 2010 (UTC)[reply]

That's just rounding, as has already been mentioned: str() on floats formats them with, I believe, 12 significant digits, which hides such trivial "errors" as these. For example, I get str(0.3/0.1)=='3.0' but repr(0.3/0.1)=='2.9999999999999996'. --Tardis (talk) 20:38, 29 November 2010 (UTC)[reply]
Yes, str(n) only formats your floating point numbers like in the case above, but it is expressed more concisely and doesn't let you choose the number of significants digits, which is set to 12 in str(n) and is optional in round(n[, ndigits]).Trustinchaos (talk) 11:44, 30 November 2010 (UTC)[reply]

Microphones and Sound cards

Hi, I've toying with the idea of getting a new microphone and sound card, which microphones and sound cards produce a crisp and clear recording of speech, such as File:The Game.ogg? I currently have a Windows Vista laptop with a Realtek High Definition Audio. Thanks --George2001hi 11:45, 29 November 2010 (UTC)[reply]

Is there any reason why you feel you need a new sound card? Nil Einne (talk) 15:51, 29 November 2010 (UTC)[reply]
Wikipedia:WikiProject Spoken Wikipedia/Recording guidelines has some guidelines about recording speech; there's a lot more to it than the microphone (and really any sound card should work fine). Wikipedia:WikiProject Spoken Wikipedia/Recording guidelines/Sample configurations lists some of the microphones people have used; very few seem to have anything other than basic hardware. -- Finlay McWalter ☻ Talk 16:26, 29 November 2010 (UTC)[reply]
Thanks, for the help. I was just wondering if the sound card was poor or outdated. --George2001hi 17:27, 29 November 2010 (UTC)[reply]
(e/c) Be wary of buying a microphone that requires a lot of auxiliary equipment. To demonstrate what I mean, my experience: I used to use a very cheap, old headset for recordings. Its sound was a little shallow and tinny as a result (made worse by the fact that I have the naturally higher voice of a young woman), but it was otherwise clear and fuzz-free. About two or three years ago, in order to play an older female character in a more professional recording, I was asked to get a serious amateur microphone that would have a richer sound, to help balance the limitation of my voice wrt this character. Without really knowing what I was doing, I bought a decent-ish electret condenser microphone. I then found that it required pre-amplification, so I had to buy a very small pre-amplifier. Also, didn't have the right port for the jack, so I purchased an expensive (for what it was) converter. Once I finally got it all working, the sound was rich and warm, yes, and I sounded better. But, because it wasn't that directional, was sensitive, and not top of the range, I got a lot of fuzzy background noise, picked up from my computer fan. I then had to make a small sound booth, rather like this, to house the microphone. Also had to stack books on a surface before the microphone would reach my standing height. I'd spent way more than I had intended to, had big books and a cumbersome foam-filled box cluttering my desk, and still found it fiddly and bothersome to set up and use. In the end, I scrapped the approach altogether and bought a new, quality headset: I get fine sound (not as warm, but good enough), freedom to record standing or sitting, no unwanted noise (from fans or speakers), and it's USB and plug-and-play. I also don't get variations in the volume just because I happen to shift my body position. Bonus: also perfect for Skype, gaming, etc and easy to stow away. If you're not attempting to set up an actual recording booth at home, then I suggest keeping it simple and multi-functional. Go for a good headset perhaps—there are dozens with great reviews. As for sound cards, the one you have should be fine; probably only an audiophile or a professional would be able to tell the difference between the average sound card and a top-end one. Maedin\talk 18:04, 29 November 2010 (UTC)[reply]
Thank you, now that's going the extra mile - your advice is greatly appreciated and will taking into account. Sorry if I sound bothersome, can I ask what your quality microphone is? Thank you. --George2001hi 18:36, 29 November 2010 (UTC)[reply]
Are you referring to the serious microphone or the headset? The microphone that I gave up on was a Sony, like this, only not quite that expensive, if I recall correctly. As you can tell from the reviews, it's meant more for recording music than speech. The headset I use now is a Logitech, but I couldn't find the model (it's older) on Amazon, but likely comparative to this one: [17]. I imagine that one of the cheaper ones would also do great (depending, of course, on your intended usage), as would a number of other good brands in headsets. A general search for headsets will bring up a lot of decent options. As a very general guide, I wouldn't spend less than £15 or more than £30, but ymmv!  :) Maedin\talk 19:01, 29 November 2010 (UTC)[reply]

Computer modelling of Artificial consciousness

"Computer modelling shows that even consciousness can be generated with very small neural circuits....only a few thousand could be enough to generate consciousness." from http://www.sciencedaily.com/releases/2009/11/091117124009.htm ... 92.24.176.72 (talk) 14:32, 29 November 2010 (UTC)[reply]

The above question has been asked on the science desk; just giving any of the denizens here who don't answer the science desk a heads up (how may are there?) CS Miller (talk) 16:19, 29 November 2010 (UTC)[reply]

Processor upgrade

Firstly may I state that I know upgrading the processor on my laptop would void the manufacturers warranty and that it can cause compatibility issues. I fully understand that, but I need to check two things:


-A) I have an Acer Aspire 5542 with a AMD M880G motherboard with a AMD Athlon II Dual-core M320 processor. Initially when I bought my laptop this was sufficient but I'm starting to feel the effects of not having a powerful enough processor. I have sufficient RAM for my needs and a decent graphics card, so I'm assuming my poor performance is due to the processor. Is this chip set soldered in to the motherboard and thus unable to be upgraded?

-B) Assuming it's upgradable, where can I find which processors I would be able to upgrade to?

I can't find about either question in the computer manual or through a quick Google search, so I'm seeking advice from you guys. May I also state that I have no intention of doing this myself and it would be done through a technician, but I want to avoid the cost of getting advice from one beforehand. Thanks for your help. Regards, --—Cyclonenim | Chat  17:58, 29 November 2010 (UTC)[reply]

A processor is never soldered into a motherboard. The processor models that are compatible with your system are listed at List of AMD Turion microprocessors#Turion II / Turion II Ultra. You should be able to use any of the "Caspian" types -- the ones that use the S1G3 socket. Looie496 (talk) 19:04, 29 November 2010 (UTC)[reply]
Any idea where I could purchase a Turion II Ultra M660? And ah right, I just read an article that said sometimes they're fixed to the board? Never mind! This is why I love Wikipedia and the reference desk! Thanks Regards, --—Cyclonenim | Chat  19:06, 29 November 2010 (UTC)[reply]
If this is what your motherboard looks like, you can see the empty CPU socket in the image. That is where you'd remove/replace the CPU. As for finding a CPU, there are many places that sell processors. For example, you can try the first hit I got from Google. -- kainaw™ 19:21, 29 November 2010 (UTC)[reply]
Does it involve any complicated working with the BIOS or anything though? I consider myself competent with computers but not much more. If I literally just have to swap things over then I'd be willing to that, or maybe if I can find a detailed guide. Regards, --—Cyclonenim | Chat  19:46, 29 November 2010 (UTC)[reply]

Firefox and Keyboard Shortcut customization

Mozilla Firefox's official Keyboard Shortcuts guide explicitly states: "Firefox does not provide any method of customizing keyboard shortcuts." This seems like intentional, heavy-handed, and forceful, especially for a free and open-source software package that allows all kinds of other customizations. I suspect this decision has something to do with maintaining "brand consistency" or precluding an entire class of phishing attacks, but I'm looking for an official explanation behind this design decision. Can anyone help me find an official explanation from Mozilla (a developer-blog, program documentation, mailing list, etc.) explaining why they do not allow custom keyboard-shortcuts? (Addendum, I found this background theory on Mozilla key bindings, but I'm really looking more for a high-level, "we chose to do it this way because ..." explanation). Nimur (talk) 18:55, 29 November 2010 (UTC)[reply]

I think they chose to do it this way because they generally tend to leave non-essential stuff to extensions and add-on packages. Installing keyconfig takes about a minute.—Emil J. 19:21, 29 November 2010 (UTC)[reply]
Yes, and there are plenty of other key configuration plugins for Firefox. Vimperator radically changes the key bindings to use those of the Vim text editor. There are many other such plugins. –Tom Morris (talk) 02:37, 30 November 2010 (UTC)[reply]

Office 03, Excel, tilde issue in VLOOKUP

Is the tilde some kind of reserved character in Excel, or does it confuse Excel in some other counterintuitive way?

I have a large spreadsheet of client investment data by account, a direct but seriously ugly dump from one of our reporting systems. In order to more easily make sense of this data, I need to map basic account numbers to a "Holding Type". I've added a proper column, filled it with a VLOOKUP call to an external data table, thusly: 

   =VLOOKUP(E2, [XrefTable.xls]Sheet1!$A$2:$E$506, 5, FALSE)

This works wonderfully -- and then feeds into a Pivot Table -- except for one thing:

A dozen or so account numbers contain a "~" as the leading character. No problem, I sez to myself, I should create the XrefTable data with the tildes anyway since they don't ever change. But, ALL of the VLOOKUP calls FAIL and return "#N/A" for any account that begins with that damn tilde.

This is clearly documented in the VLOOKUP help: If VLOOKUP can't find lookup_value, and range_lookup is FALSE, VLOOKUP returns the #N/A value. The XrefTable is sorted on account number, and most of the numbers are strictly numeric, but some aren't, and I have tried both of the "sort anything that looks like a number" options.

So, WHY can't VLOOKUP find a lookup value that starts with a tilde in the first place?? It can't be a known bug in an 8-year-old product, can it? I thought it might treat ~ as some kind of metacharacter and throw off the sort or lookup, but can't find anything in the online help.

Anybody ever run into this issue before, and solve it?

Thanks much, DaHorsesMouth (talk) 20:07, 29 November 2010 (UTC)[reply]

  • I should probably also mention :-) -- I understand the part about using ~ when typed literally into a search box or the like. In this particular case, since I'm not going to be the only user of the resulting table, I have a strong aversion to editing the raw data. The tilde in question appears as the leading character in two data fields, not as a literal in my function or something I'm entering directly.

Besides, even if ~ says "do not modify the next character", shouldn't it STILL match the two strings properly?

DaHorsesMouth (talk) 21:00, 29 November 2010 (UTC)[reply]

MS suggests that you'd normally use a double tilde ("~~") in these cases [18]. As you can't modify the raw data you'll probably have to use an expression in the spreadsheet to modify the search string before handing it to VLOOKUP. Blakk and ekka 13:38, 30 November 2010 (UTC)[reply]

Oops, my mistake! I meant .dat file (continued from here)

I just looked at it again, and it's a .dat file, not a .bat. should I do? (if it means anything, it's 35 kB)--72.178.134.134 (talk) 21:20, 29 November 2010 (UTC)[reply]

If its a .dat file, then its ussually a serialized data file of some sort. If you don't know what to do with it, you probably should either delete it/or ignore it.Smallman12q (talk) 21:29, 29 November 2010 (UTC)[reply]
A .dat file attached to email may be winmail.dat, a container of the actual attachment sometimes sent by Outlook clients. Unilynx (talk) 07:26, 30 November 2010 (UTC)[reply]

DVD -/+R

Working on an iMac G5, OSX, version 10.5.8. I want to download some movies and burn them to disk. I've never done it before, though I've used Toast Titanium to burn some pdfs to CDR disks. So I have a couple of questions. I see the DVD+R and DVD-R formats. I looked at the article on them but didn't get much out of it other than that it probably doesn't matter but DVD+R is slightly better. I just wanted to first confirm that these type formats should work with my computer... yes? and wanted to know if the brand matters much and if so, what brand is recommended. Second, I want to burn a movie that is more than two hours long. I went to a store and looked at the disks and they all list 4.7 GBs and "120 minutes." Does that mean it can only store 120 minutes of material so I would have to break the movie up into parts? (I have no idea how to do that).---141.155.159.27 (talk) 23:17, 29 November 2010 (UTC)[reply]

What format will you be downloading and saving your movies in? Most commercial dvds are 8.something GB, while writable DVDs are the mentioned 4.7. A program like DVD Shrink (which unfortunately appears to be Windows only) will shrink a DVD file to the desired size (trading quality for a smaller size). Buddy431 (talk) 23:40, 29 November 2010 (UTC)[reply]
Check the label on the edge of your DVD drive tray, if that doesn't say, look up its model online, though it probably won't matter as you suspect. The brand / type only matters if you need to support extra-fast writing (which requires a more durable disc), or want particularly long-lived backups; also some have better labels/surfaces than others. As you can see at DVD there are capacities other than 4.7GB (and this will be decimal, not binary GB [4700 MB, not 4810]), but 4.7 is by far the most popular and simplest to write to. The "120 minutes" is a gross estimate for the ignorant masses. You can store much more than 120 minutes of media, but the longer it is, the lower the quality (the sum of audio quality and video quality [including resolution]) must be to fit in the given space. This is particularly problematic if you want to create a DVD-Video disc, as they use an incredibly old and comparatively inefficient format (MPEG-2). If you want to create a disc that you can give to someone for them to watch most anywhere, DVD-Video is probably your only sane choice. If it's just for yourself, it will save you a great deal of time, effort, and cost to setup a media PC, which you can transfer media to over the network or via USB stick. As for software, you might try ConvertXtoDVD or tovid. ¦ Reisio (talk) 00:20, 30 November 2010 (UTC)[reply]
I appreciate your responses but you're almost speaking a foreign language. Re:Buddy431's response: What format? I have no idea. I thought I could use Titanium Toast to burn the DVD as that is the only program I have. Will that work? Is there a free better program I could download? Re Reisio's post, you're talking over my head. I visited the links for setting up a media PC and DVD-Video but it's all Greek.--141.155.159.27 (talk) 01:34, 30 November 2010 (UTC)[reply]
Where will you download the movies from? That will allow us to determine what the file format is. Buddy431 (talk) 02:44, 30 November 2010 (UTC)[reply]
Titanium Toast appears to be a powerful program, and should do whatever you need to with it. Using a mac, your alternatives are limited. However, searching "free DVD burner for mac" nets this list. The Xilisoft product, for example, has a free trial version that watermarks your output. If you like it, you can buy it for 50 USD, cheaper than the Roxio product that you're looking at. Some of the other ones can be had for even cheaper, and offer free trial versions (but that limit how much you can convert with the free trial version). It's likely (though I've not tried any of the products) that the more expensive ones are either more powerful or easier to use (or both).
You can try any of these programs for free to see if they do what you want. DVDs themselves are cheap, so if you screw up, it's no great cost. Try the Xilisoft product and see if you can get your full program on one DVD. If you can, you can buy the full program (or just live with their watermark). Buddy431 (talk) 03:11, 30 November 2010 (UTC)[reply]


November 30

China e-mail security

With Operation Aurora in mind, I have been wondering about the potential for compromised privacy of e-mail messages sent from China to places outside China, and of those sent from outside China to places in China. What precautions should be taken by a person with an e-mail account hosted outside China?
(As with all questions which I post at the Wikipedia Reference Desk, I appreciate being told not only answers that are accurate, complete, concise, and clearly expressed, but also [1] supporting references, [2] the research process [how the information was found], [3] research recommendations [how I can find answers to similar questions], [4] leads and partial answers, and [5] other closely related information. )
—Wavelength (talk) 00:30, 30 November 2010 (UTC)[reply]

We need some clarification on your question. By What precautions should be taken by a person with an e-mail account hosted outside China, do you mean "a person who lives in China" or "a person who lives outside China"?
Either way, as our E-mail privacy and Email articles detail, e-mail is sent unencrypted and with no way to guard against tampering with the headers or the message itself. Any e-mail that is sent, anywhere in the world, can be read by any computer along the route path to the destination mail server. (See traceroute for a way to try to discern this.) Since the e-mail is unencrypted, people who own or control these computers can read or modify the message while in transit. By the way, various Western countries are alleged to eavesdrop on e-mail on a large scale, too, by the way, via Project ECHELON and Carnivore (software) and their relatives.
It is possible to prevent e-mail snooping by using encryption on your messages. If you use a large enough encryption key, brute-force techniques used by any eavesdropper will be ineffective. Comet Tuttle (talk) 01:44, 30 November 2010 (UTC)[reply]
I was not aware that the country of residence of the person with the e-mail account was an important criterion for determining what precautions should be taken, but I am interested in all important distinctions. What precautions should be taken (a) by a person living in China with an e-mail account hosted outside China, and (b) by a person living outside China with an e-mail account hosted outside China? Also, what about (c) a person who lives outside China with an e-mail account outside China, but who travels in China and sends and receives e-mail messages by means of a wireless device?
I have read most of the information in the six articles which you linked, but I hope to read them again later in more depth. Thank you for those links.
—Wavelength (talk) 03:41, 30 November 2010 (UTC)[reply]
In light of echelon, carnivore, aurora, etc, one who is concerned about privacy may be interested in Pretty_Good_Privacy, or perhaps Freenet. SemanticMantis (talk) 03:27, 30 November 2010 (UTC)[reply]
Thank you for providing links to those articles. E-mail security is complicated by so many concepts and terms—enough to make a person wish for a world in which everyone can and does trust everyone else all the time.
—Wavelength (talk) 17:54, 30 November 2010 (UTC)[reply]
I would also recommend a read of the electronic envelope concept, and GNU Privacy Guard, a free and open source implementation that provides for "pretty good privacy." Also consider avoiding the use of the EMAIL technology in general: the specific implementation of electronic messaging that is known as "email" has inherent flaws as a result of its legacy architecture and a protocol that pre-dates the modern internet. Consider an alternative technology, such as XMPP (commonly known as Jabber), which by design provide for a security layer, a message-certification authority, and message-relay encryption (Transport Layer Security). To the average user, you really won't know the difference whether your messages to your acquaintances are delivered by XMPP or RFC5322 email - but the newer technology inherently allows for more transport security, message-tampering evidence, and authenticated sources. Nimur (talk) 18:42, 30 November 2010 (UTC)[reply]
The reason I had asked whether the user was inside or outside China is that if the government of China is your concern, then since the assumption is that the Chinese government can read every communication that is sent or received by any person within China, everything sent or received by a person in China must be encrypted in order to discourage snooping.
If the user is in, say, Great Britain, and is sending an e-mail to a person in France, it seems unlikely that the e-mail is going to hop through a Chinese computer on the way to its destination ... but you never know, so encrypting the e-mail with sufficient encryption strength should prevent snooping by the government of China in the unlikely event that the e-mail does hop through China during its journey. The main reason everyone doesn't do this already is because it's a pain, since encryption is unfortunately not part of the e-mail standard. By contrast, encryption is in widespread use in Web browsing when you purchase something (see Transport Layer Security). Not to confuse the issue further, but it is common for e-mail clients to use encryption when they communicate with their e-mail server — and then the e-mail server turns around and sends the e-mail in unencrypted plaintext! Comet Tuttle (talk) 18:44, 30 November 2010 (UTC)[reply]
Thank you, Nimur and Comet Tuttle, for the additional replies with links to additional articles. I have "read" much of the information in the articles, to the extent that I can accurately call it "reading" when I am sometimes reading words more than understanding the immediate context. I hope to read them again later, after I have fortified my knowledge by a study of computer terminology, perhaps by means of Category:Glossaries on computers.
—Wavelength (talk) 22:00, 30 November 2010 (UTC)[reply]

XBOX 360 CD Rip to Flash Drive?

I want to be able to listen to custom music in NHL 11 on my 4gb XBOX 360. I don't have an external hard drive. Is it possible to rip a CD directly to a flash drive for use in the game instead? 67.142.173.25 (talk) 02:45, 30 November 2010 (UTC)[reply]

You'll need to rip the CD's contents to a computer, by using a program like Windows Media Player, then copying the files, from your computer, to the flash drive. I'm not aware of a program or process that can directly copy it to a flash drive, from a CD. Thanks --George2001hi 13:20, 30 November 2010 (UTC)[reply]
That won't work, because the Xbox 360 won't be able to read the files from your flash drive. When you insert a USB thumbstick into one of the USB ports on a 360, it asks if it can delete everything on the flash drive and prepare it for Xbox 360-only storage. Once you do so, the flash drive is still a FAT32 device, containing one folder entitled "Xbox360" and marked "hidden", and then inside that folder are placed numerous large files in some proprietary Microsoft format, probably encrypted; when you copy an XBLA game (or whatever) to your thumbstick, the game is placed within one of those large files. I just tried using my 360 to rip a CD to the hard disc but then the Xbox would not allow me to copy the music files to the USB thumbstick like you can with 360 games, profiles, save files, etc. The 360 also wouldn't allow me to rip directly to the flash drive when I booted the 360 with no hard disc. One possibility, if you have a PC on your network, is to rip the CD to your PC's hard disc and use the Xbox to stream the music from your PC. (Go to "My Xbox -> Music Library -> Computer".) Comet Tuttle (talk) 18:33, 30 November 2010 (UTC)[reply]

want the pictures back, please help

had visited taj mahal with my wife once and i stored the photos in my laptop but unfortunately my brother formatted the computed about twice now. is there a way still i can get those treasured pics back before my wife is out of the hosp? —Preceding unsigned comment added by 203.122.36.6 (talk) 12:57, 30 November 2010 (UTC)[reply]

You'll need to supply some details of the model, original/post-format operating systems and which tools your brother used to get specific help here. If your pictures are really that valuable you'd be best advised to take the PC to your nearest reputable computer store rather than attempt a recovery yourself. Blakk and ekka 13:15, 30 November 2010 (UTC)[reply]
It is also important that you stop using the computer now to increase the chances of finding anything. Further use of the computer increases the chances of overriding the old files (if they are still there). Trustinchaos (talk) 13:52, 30 November 2010 (UTC)[reply]
It depends on whether the formatting was a quick format or a full format. A quick format really just deletes files and marks the sectors as empty, so something like "PC Inspector Smart Recovery" (or a newer equivalent) might recover some of the JPEG files if they have not been overwritten. Don't install anything or store anything on the hard drive of the laptop, but if you know what you are doing, you could try a recovery yourself from another computer (or run the recovery software from a flash drive). As mentioned above, for valuable pictures, it is safer to take the machine to an expert, but you should be aware that some (or most or all) of the pictures might be unrecoverable, even using the (very expensive) methods and specialist variable track readers of espionage and criminal investigations. If the sectors have been overwritten twice with new operating systems, then it is going to be impossible or prohibitively expensive to recover the pictures (unless money is no object), but if they happen to be stored in sectors that have not been overwritten then there is a good chance that they are still there and can be recovered using simple software. Dbfirs 19:00, 30 November 2010 (UTC)[reply]
Which simple software? Gparted can restore partitions, if the user is extremely technically proficient; but it can not restore file-systems. Recuva might be of some assistance, but it probably won't work after formatting the disk (though it claims to have some chance of success). Data recovery article has some uncited claims. I am not aware of software that makes it easy to restore files after the file-system has been reformatted. The data may "theoretically" still exist - the bits may still be on the disk, provided that they haven't been overwritten yet - but that data is nonfunctional without a correct file system that puts it all together. Modern file-systems are very complicated - data may be fragmented, strobed, or stored in non-contiguous blocks on disk - so without the correct file system in place, it's as impossible as piecing together a shattered cup. All the pieces are still present (except any that have been overwritten or zeroed), but that does not mean they can be easily glued back together. We can hope and speculate that files were contiguous and no parts were overwritten, but in general that is not the case. Nimur (talk) 19:08, 30 November 2010 (UTC)[reply]

Easy Android OS Question

Resolved

I'm curious about something. How does Google's Android handle updates to apps? Do you have to go to the App store and manually update them or are updates handled automatically (the way Google Chrome is updated automatically)? A Quest For Knowledge (talk) 16:03, 30 November 2010 (UTC)[reply]

I found someone who has an Android and apparently, there's a setting that lets you do it either way. Thanks. A Quest For Knowledge (talk) 16:38, 30 November 2010 (UTC)[reply]

More difficult IE7 certificate error question

Something's wrong with IE7 on my computer. Whenever I visit a web site that is signed with a certificate, I always get an error saying that the certificate is invalid - even when the certificate is valid. Not even sure where to begin. PS. I cannot install IE8 or 9 as it's forbidden by our IT dept. A Quest For Knowledge (talk) 16:36, 30 November 2010 (UTC)[reply]

If you do not have administrative rights on your work computer, then it is probably better to ask your IT department to fix the problem. Do all other work computers exhibit the same behaviour? Dbfirs 18:28, 30 November 2010 (UTC)[reply]
This might be a configuration error, or it may be intentional. If you work in a corporate environment or government agency that actually values security, your computer(s) probably have few or zero pre-installed root certificate authorities. This means that no computers are trustworthy (unless they are authenticated by your organization). On most standard Windows computers, a few root certificate authorities - that is, private agencies that are trusted by Microsoft and IANA, are pre-installed. Anything that these root authorities certify is then trusted via a chain of trust. So, by default, most Windows computers are "hard-wired" to trust VeriSign and Thawte - and by proxy, Google, and Yahoo, and eBay, and so on. Of course, if your organization deals with sensitive information, and as a rule doesn't trust outside agencies (such as VeriSign or Microsoft), then they will not consider any website "authenticated" unless it can trace its chain back to the agency's internal security root. Compare, for example, the root certificate authorities trusted by Mozilla. Nimur (talk) 19:16, 30 November 2010 (UTC)[reply]
You could use another browser instead on a flash drive, if the administraitor allows you to. General Rommel (talk) 21:22, 30 November 2010 (UTC)[reply]

Non-WYSIWYG free online wiki?

I want to set up a wiki but can't run my own wiki software (running MediaWiki is the ideal but not achievable right now). As a Wikipedia habitué, I like the MediaWiki syntax (logic/content/function-driven) and am appalled at the idea of a wiki with a WYSIWYG editor (pbworks, wikispaces, moodle). By these criteria, I believe the only option is wikidot (quite dissimilar to MediaWiki syntax, and perhaps a chore for my collaborators to acquire a not-directly-transferable skill in it, but following comparable principles). Or is there another one I'm missing? Wareh (talk) 19:24, 30 November 2010 (UTC)[reply]

php

In php, what is the opposite of "array_reverse" 82.44.55.25 (talk) 20:29, 30 November 2010 (UTC)[reply]

There isn't an opposite of it. All it does is reverse the order of elements in an array. "Reverse" is relative to the starting array. Reverse the input array twice and it's the original input array again. If you're worried that the elements are unshuffled (Even though the keys are), just run ksort on the array to re-sort it by keys. --Mr.98 (talk) 20:37, 30 November 2010 (UTC)[reply]
Thank you for the answer but I am confused. In the php file there is the line "$text= array_reverse($text);" which when echoed produces a list which is in backwards order to the original. I want it to be in the same order as the input. I tried "$text= array($text);" but that didn't work 82.44.55.25 (talk) 21:20, 30 November 2010 (UTC)[reply]
str_split? 118.96.156.106 (talk) 23:46, 30 November 2010 (UTC)[reply]
If you don't want it reversed, you just don't use the function (e.g. comment out that line of code). If you have already run it through the function and want it reversed again, just run it through array_reverse again, and it will be the same as the input was. --Mr.98 (talk) 03:20, 1 December 2010 (UTC)[reply]

Grouping similar images

Is there any software that will take a large collection of images and automatically sort them into groups that are similar in appearance? Thanks 92.28.247.40 (talk) 22:07, 30 November 2010 (UTC)[reply]

Two programs I know of; ImgSearch and ImageSorter 82.44.55.25 (talk) 23:23, 30 November 2010 (UTC)[reply]

December 1

Regular expression look arounds

I'm trying to write a perl regular expression in the following manner: I have a string with possible letters of abcd. The pattern will match the string if it's abd, abcd, or abd but nothing else. So far I have this:

  • (a)?bc?d

Obviously this is wrong, because it matches bcd. How to I write a lookaround for c to only be allowed if (a) doesn't evaluate to empty? Magog the Ogre (talk) 03:07, 1 December 2010 (UTC)[reply]

First, since you're matching the whole string, you need to anchor the search with ^ and $. Next, since you put a ? after a, I suppose you meant "abd, abcd, or bcd" instead of repeating abd in the specification. Then I'd just write the three alternatives explicitly:
  • ^(ab|abc|bc)d$
or you can combine two of them:
  • ^(abc?|bc)d$
This is simpler than anything you could do with lookaheads.
If a, b, and c really are long expressions themselves, then I wouldn't try to do it all in the regexp. Instead I'd do
  • ^(a?)b(c?)d$
and then test whether at least one of $1 and $2 was non-empty. --Anonymous, 03:30 UTC, December 1, 2010.
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