Wikipedia:Reference desk/Computing
of the Wikipedia reference desk.
Main page: Help searching Wikipedia
How can I get my question answered?
- Select the section of the desk that best fits the general topic of your question (see the navigation column to the right).
- Post your question to only one section, providing a short header that gives the topic of your question.
- Type '~~~~' (that is, four tilde characters) at the end – this signs and dates your contribution so we know who wrote what and when.
- Don't post personal contact information – it will be removed. Any answers will be provided here.
- Please be as specific as possible, and include all relevant context – the usefulness of answers may depend on the context.
- Note:
- We don't answer (and may remove) questions that require medical diagnosis or legal advice.
- We don't answer requests for opinions, predictions or debate.
- We don't do your homework for you, though we'll help you past the stuck point.
- We don't conduct original research or provide a free source of ideas, but we'll help you find information you need.
How do I answer a question?
Main page: Wikipedia:Reference desk/Guidelines
- The best answers address the question directly, and back up facts with wikilinks and links to sources. Do not edit others' comments and do not give any medical or legal advice.
April 14
bar codes
i was wondering if a carefully crafted bar code can be used to exploit a scanner. thanks, 70.114.248.114 (talk) 00:16, 14 April 2013 (UTC)
- Exploit to do what? OsmanRF34 (talk) 00:48, 14 April 2013 (UTC)
- It is conceivable that a badly designed program could mishandle input data and it could cause some exploit. It's a very small amount of data though (relatively; even QR codes are not especially large) so they would need to boostrap larger code to do much interesting. I am sure there have been examples of this (I seem to remember hearing some) but they're exceedingly rare.
- If you mean exploit in other ways though, like lower the price, that's a different question. Most basic UPC barcodes only contain a SKU number, and the relevant data is in a database. There have been UPC swapping scams though. Shadowjams (talk) 00:55, 14 April 2013 (UTC)
Why is malware combined with useful downloads?
I recently downloaded some malware while downloading something I actually needed. In this case, it was a program that takes over my search called "Delta Toolbar". I'm usually good with checking every time I'm installing something to see if it's asking me to install whatever program it wants to use to give me extra search bars or overhaul my search what have you, but it does always seem to be related to searching. Is this how those legitimate downloads are able to make money since they're free? Ryan Vesey 01:09, 14 April 2013 (UTC)
- That's what I would guess. I was converting a file type last night online, and apparently had to download an "installer" to convert the file and, in a weaker moment, did not notice that I was downloading something else with the installer. I got this stupid Delta Search thing too, so I assume it has something to do with money. Google it and you will read all kinds of things about it. It took me a half hour to get everything from it off my computer and then I had to uninstall and reinstall Chrome to remove all of the crap it added to that. Go Phightins! 01:16, 14 April 2013 (UTC)
- The toolbar developers pay third parties to bundle them with their products ("pay-per-install"). They make the money back through advertising displayed on the search results page and/or tracking the web sites you visit and selling that information.
- Sometimes it's the author of the other product who bundles the toolbar to get some extra revenue, but in this case you will always, I think, be given the option to not install it. (PDFCreator is an example of an open-source product that does this.) However, there are also scammy web sites that redistribute legitimate software from other sites with an adware-installing wrapper. So you should avoid downloading even well-known freeware from random sites. Get it from the official site mentioned in the Wikipedia article, if possible.
- (Incidentally, another scam you've probably noticed is ads that appear on software download pages that look like "download" buttons, but actually download something entirely different. If you don't have an ad blocker, it can be hard to find the real download button even on the official download page. So be careful out there.) -- BenRG 02:53, 14 April 2013 (UTC)
- I'm almost positive I had the opportunity to stop this one. I opened the install window, and started pressing next like a madman. I was glancing at the windows, but not well enough and I realized I hadn't unchecked a bit of malware. I clicked cancel on the next window hoping I could start over; however, it considered cancel to mean "no, I don't want to install this second bit of malware, go ahead and install everything else now". There was no option to stop the download at that point, even task manager didn't take care of it so I got to watch as my computer installed the malware, it was frustrating to say the least. I do most of my downloading from CNET, but it can get really frustrating because once you click download, it confuses you by throwing up 1000 things with download buttons. Ryan Vesey 03:05, 14 April 2013 (UTC)
- You have to be careful about where you are downloading from. Even with legit services, they like to trick you into downloading something else - usually a browser add-on or a program to "scan" your computer for errors. Bubba73 You talkin' to me? 03:22, 14 April 2013 (UTC)
- So I realized I hadn't downloaded what I wanted to at all so I took another look. The download was through adf.ly, which requires you to stare at an ad for 5 seconds and the download link is in the upper right hand corner. There is a much larger download button in the center (the ad) and I went for that one. On another note, a couple years ago I had a popup tell me that my computer had 5 viruses and that I should download a new program to get rid of them. It was a trojan and within a week the computer wouldn't even start. Ryan Vesey 03:33, 14 April 2013 (UTC)
- You have to be careful about where you are downloading from. Even with legit services, they like to trick you into downloading something else - usually a browser add-on or a program to "scan" your computer for errors. Bubba73 You talkin' to me? 03:22, 14 April 2013 (UTC)
- Yes, a couple of I've fallen for that trick of the large download button in the center when the one you want is smaller and in the corner. Now I always try to watch for that. Bubba73 You talkin' to me? 04:06, 14 April 2013 (UTC)
- It is very annoying this crossing the line tat is done on both sides and it just makes for a worse time for all. Personally I consider that I should have a look at somebody's ads if that's the price a person wants me to pay for something, but then you have people with ad blockers who ruin their revenue stream. So then the ads get mean and nasty in their tricks getting people to do things they have not and do not want to agree with. So users have to avoid and be careful of the whole business and treat all ads as malware in the offing. In the end the only winners are large corporations like Microsoft or Apple where people have a good idea what they're getting and just pay the money rather than bothering with all the worry, people without much money are fed viruses. Dmcq (talk) 10:34, 14 April 2013 (UTC)
- Even if you download Adobe Reader directly from Adobe, it tries to get you to install McAfee (defaulting to do it), IIRC. Bubba73 You talkin' to me? 17:47, 14 April 2013 (UTC)
bootstrapping/changing ip address
1: my router is configured to have a dynamic ip, but whenever the lease is up, it does not change. what causes this, and how do i change it manually (if i can)?
2: if someone can give me a short example of python code that bootstraps more complex code, that would be great. thank you, 70.114.248.114 (talk) 03:53, 14 April 2013 (UTC)
- Are you losing connectivity to your ISP? As I understand it the lease should never expire as long as you remain connected (assuming the DHCP server is working properly). Looie496 (talk) 04:02, 14 April 2013 (UTC)
- You don't generally change addresses when a (DHCP or apartment) lease expires. ISPs use dynamic IPs so that they don't have to pay for IP addresses for people who aren't connected; they have no reason to move you as long as you are connected. If you stay disconnected for long enough the ISP will assign the address to someone else and then you'll get a new one, but I couldn't tell you how long it would take (minutes/hours?).
- I don't understand your second question. What kind of bootstrapping do you want? -- BenRG 04:51, 14 April 2013 (UTC)
- Note that, as a general rule, ISPs use RADIUS to allocate IP addresses, not DHCP. There's no concept of a "lease". That said, the solution of turning the box that interfaces to your ISP (normally a DSL or cable modem, rather than a straight router) off for a while would get a new IP address.--Phil Holmes (talk) 10:53, 14 April 2013 (UTC)
so, if you have a dynamic ip, it does not change at regular intervals? but only when disconnected for some time? 70.114.248.114 (talk) 00:20, 15 April 2013 (UTC) also, how does an ip scrambler work? 70.114.248.114 (talk) 00:21, 15 April 2013 (UTC)
- My IP address changes at random, sometimes in the middle of editing, but this is because I have an intermittent internet connection via a long chain of microwave links, and sometimes this can be very frustrating (though not a problem in Wikipedia because I always edit from my account). Most people's IP addresses are fairly static as explained above. Why would you want to keep changing IP addresses? I trust you are not aiming to avoid blocks. (That's genuine trust, not a snide comment — I've no reason to think that any of your edits have been vandalism.) Dbfirs 07:11, 15 April 2013 (UTC)
thanks for the trust (we need more of that in this world). since some sites use permanent ip blocks, i just wanna be able to change mine in case i find a site that blocked the last person to have my ip. thanks all for the info, 70.114.248.114 (talk) 21:15, 15 April 2013 (UTC)
emacs descent into wordprocessorhood
I've got a new version of emacs (23.2.1) on one of my computers, and it's behaving differently when long lines are wrapped. Control-N and control-P are moving between display lines, not actual lines. That is, if I've got a narrow window containing two lines of text:
The quick brown fox \ jumps over the lazy dog
where the cursor is under the q of "quick" and the first line is wrapped, control-N moves to the s of "jumps".
That is, it moves to another position on the same line. That's not what control-N is supposed to do! This may be fine for the word processor crowd, but I've been using emacs for (lemme see) 33 years now, and my fingers and lower spinal cord are pretty used to it working the old way.
Presumably there's a mode flag to turn this ghastly new behavior off -- anybody know what it is? —Steve Summit (talk) 12:29, 14 April 2013 (UTC)
- You'd never have this problem with vi Rojomoke (talk) 12:32, 14 April 2013 (UTC)
- Har har. (I'd just have all those other problems!)
- Anyway, if I'd just done a google search, I could have answered my own question.
- From http://www.gnu.org/software/emacs/manual/html_node/emacs/Moving-Point.html:
- "When a line of text in the buffer is longer than the width of the window [...]
- For convenience,
C-n
andC-p
move point by screen lines, as do the equivalent keys<down>
and<up>
. You can force these commands to move according to logical lines [...] by setting the variableline-move-visual
tonil
[.]"
- "For convenience". Feh. At least you can turn it off. —Steve Summit (talk) 12:37, 14 April 2013 (UTC)
- Yes, I think Mark Twain had it right: "It comes fully equipped with all the modern inconveniences." StuRat (talk) 22:30, 15 April 2013 (UTC)
TELESONIC DVD PLAYER TL-2000
Dear friends, From where can I download the USER MANUAL of the TELESONIC DVD PLAYER TL-2000. Thank you very much.175.157.168.56 (talk) 15:33, 14 April 2013 (UTC)
- Unfortunately Telesonic is a Chinese company that is involved in a great many things and has no unified web site, so this question is very difficult. It might not be possible. Looie496 (talk) 15:51, 14 April 2013 (UTC)
wikEd Bug Report Submission Help
Hello; I'm in the middle of compiling a bug report about a current incompatibility that wikEd seems to have with MathJax when this is executed via the 'Preview' function. Could any of you guys tell me at which piece of JavaScript I should point Safari 5.0.6's Web Inspector/Error Console to get the entries that I need to submit for this bug report?
Thanks,
— RandomDSdevel (talk) 21:53, 14 April 2013 (UTC)
- Um…hello, anybody home? —RandomDSdevel (talk) 19:31, 15 April 2013 (UTC)
- Nobody who knows the answer, apparently. Looie496 (talk) 20:44, 15 April 2013 (UTC)
- Okay, never mind; I think that I figured it out…I've just never used Safari's debugger before and was confused when it selected one of the extensions that I had enabled instead of some web page code when I started to debug and check for errors. I think, though, that it wants me to step through everything on its list. In that case, should I check the Web Inspector's 'Resources' tab to see what piece of JavaScript gets loaded first and go from there?
- Nobody who knows the answer, apparently. Looie496 (talk) 20:44, 15 April 2013 (UTC)
April 15
message notification
when someone leaves a message on my talk page, and i get a notification when i go to any page, does the server know it's me from my ip, or cookies? if ip, given that my router uses nat, would anyone in my house get my notification when they go to this site? if so, how can i fix that? thank you, 70.114.248.114 (talk) 05:26, 15 April 2013 (UTC)
- Wikipedia recognises you via your user name, which is made (semi-)persistent via cookies. You'll get the same orange bar if you go to an internet cafe and log in from there, and you won't get the orange bar if you log out but stay connected from your home computer. Other users of the same subnet connecting via the same NATed router won't get the message bar. If someone uses your account on your machine, then they likely will. --Stephan Schulz (talk) 05:39, 15 April 2013 (UTC)
- Since the OP is an IP, the question may refer to messages on the IP's talk page. My understanding is that those are associated with the IP address, not with cookies. To avoid having other people with the same IP address see them, the simplest solution is to register an account. Looie496 (talk) 06:53, 15 April 2013 (UTC)
- (ec) I don't think they have a user name. Yes it is based on your IP. So if someone from your house or anywhere ends up using the same IP they will see the orange bar. To avoid that you would need to register an account. CambridgeBayWeather (talk) 06:55, 15 April 2013 (UTC)
- (edit conflict) ... but if you edit as an anonymous IP then anyone reading Wikipedia from the same IP address will get your messages, even if they are using a computer hundreds of miles away, and you might get messages intended for another editor. This is why creating a user name is recommended (and is the fix you need). If you are the only editor with the IP address 70.114.248.114 then there will be no problem, but if you have a changing IP address (even from the same computer at the same physical address), then you will miss messages intended for you, and other people will get your messages. Dbfirs 06:56, 15 April 2013 (UTC)
thank you all. 70.114.248.114 (talk) 21:11, 15 April 2013 (UTC)
What causes viewDidLayoutSubviews to fire?
Hi all, I'm doing an ios app, and can't work out exactly when the viewDidLayoutSubviews method is meant to execute. I can log it (using NSLog) but I can't figure out exactly when it is supposed to go off. I know some things that always make it fire, and some things that never do, but other than that, it seems to have a logic all of its own. When I update a display about 100 times, it fires once, just for good measure. If I try to deliberately update 1000 times, it does nothing. I've read the docs, but I've only found this, and it doesn't say anything much. IBE (talk) 13:19, 15 April 2013 (UTC)
- Well, that says "When a view’s bounds change, the view adjusts the position of its subviews.". So, when exactly does a view's bounds change ? StuRat (talk) 22:28, 15 April 2013 (UTC)
- Yes, but that's the 64-thousand bit question: what exactly causes that? It seems to all happen rather haphazardly. I think if you are drawing something, and it gets a bit out of kilter, it thinks something has gone wrong, eg. if it rounds a floating point number wrongly, or something like that, but I don't know exactly what. At any rate, the practical problem is more or less solved by simply not using the viewDidLayoutSubviews except at startup. Still curious if anyone knows, but when googling through stackoverflow doesn't help, usually it means the technical knowledge isn't easily accessible on the web. Not to knock the expertise here, but it's a boffin's question IBE (talk) 08:16, 17 April 2013 (UTC)
- I think you have the right idea. It's based on variables we don't know. Even if you read the code, you might not be able to predict it. So, just treat it as random. StuRat (talk) 18:10, 20 April 2013 (UTC)
Regular expression help
I'm looking for the RegEx pattern that can parse out years from bibliographic references in HTML.
Basically, I have a bunch of HTML that looks sort of like this:
<BR><BR><DT>Lastname, Firstname.<I> Title.</I> Publisher, etc., 1998. <DD>Summary here.
Repeat for many instances on any given page.
What I want is to extract the year and nothing else. There may be years in the summary that I don't want; just the years after the DT tag and before the DD tag.
Extra bonus: some of these have been added in through dumb OCR so instead of starting with a 1, they start with a lower-case L. So ideally it should also grab l998 as well in the above example. But otherwise I think it is pretty reliably in that format.
Sometimes there are more than one date in the citation. Is it possible to have one query that pulls out just the first date, but another that grabs all of the dates?
Easy way to do it with a RegEx, or not? It's OK if it is multiple queries if that is easier; there are no real performance issues, I just suck at RegEx. Thanks. --Mr.98 (talk) 14:54, 15 April 2013 (UTC)
- RegEx's don't extract things, they simply match or don't match. It's not too hard to come up with a RegEx that will match entries that have a year in them, but if you want to extract the year, you need to specify what system you are using. Looie496 (talk) 15:19, 15 April 2013 (UTC)
- I'm doing this in PHP. --Mr.98 (talk) 15:43, 15 April 2013 (UTC)
- Well, there are various ways to make this more sophisticated, but I think you should be able to use something like
<DT>[.]*(19[0-9][0-9]|l9[0-9][0-9]|20[0-1][0-9])[.]*<DD>
- which will allow you to extract the year alone as $1. Warning: it usually takes me a dozen tries when I try to do something like this. Looie496 (talk) 17:50, 15 April 2013 (UTC)
- How about skipping dates in title?
- <DT>Doe, John.<I> European economy in 1945 – 1980.</I> Publisher, etc., 1998. <DD>Summary here.
- CiaPan (talk) 08:23, 16 April 2013 (UTC)
- How about skipping dates in title?
- And what about other OCR errors such as uppercase-O for zero, lowercase-g for 9, uppercase-B for 8, and so on? You might be better off on some massive editing session, using an editor capable of block select mode, Reg-ex searching (and replacing), creating short keyboard macro sequences, and handling however many lines there are in the file. You can use these features to delete as much of the HTML as possible, leaving you with a single column of publisher and year information - and just one line for each reference. Astronaut (talk) 16:55, 16 April 2013 (UTC)
Registration
I am trying to register a new product I have just purchased.
Unfortunately I am unable to overtype serial no. on the
one you have already printed on slip, how can I register.
Donald Mathieson — Preceding unsigned comment added by 86.112.78.164 (talk) 15:26, 15 April 2013 (UTC)
- I'm afraid you are in the wrong place. You were probably trying to contact some corporation, but this is Wikipedia, an online encyclopedia. Looie496 (talk) 15:42, 15 April 2013 (UTC)
Transferring a large file to an external drive
I'm trying to copy a file that is over 6GB in size to an external drive, and Windows XP keeps saying there's not enough free space. Both the main hard drive and the external hard drive have enough free space, so my best guess is because the file size exceeds the size of the RAM. Otherwise, I'm completely at a loss. Is there anyway around this? Could Linux transfer the file? 166.193.101.13 (talk) 17:15, 15 April 2013 (UTC)
- Reformat the external drive to a modern format like ext3 (after switching to Linux of course), and the problem will go away. Hcobb (talk) 17:25, 15 April 2013 (UTC)
- I'm guessing the drive is formatted as FAT32, which has a file size limit of 4GB. XP ships with a utility creatively named "convert" which converts FAT32 volumes to NTFS. From a command prompt run convert q: /fs:ntfs where q: should be replaced by the appropriate drive letter. This will preserve all your data. There's no way to convert back, and you may have problems accessing the drive from OSes other than Windows or Linux. -- BenRG 18:29, 15 April 2013 (UTC)
- Alternatively, split the file into two or more parts (under Linux, with
split
, and reassemble them withcat
- this should work under CygWin, too). --Stephan Schulz (talk) 18:54, 15 April 2013 (UTC)
- Alternatively, split the file into two or more parts (under Linux, with
- The simplest route for you would probably be to use an archive manager such as 7-Zip to split the file into 4GB volumes. You could also in the same process compress (with 7-Zip’s “ultra” 7z/LZMA2 compression), which can under certain situations make 8GB of data into 4 or less (although merely storing the data in 4GB volumes will take less time than storing and compressing).
The more worthwhile long term action would probably be to switch the drive FS to NTFS (as already mentioned), but it depends on how much data you already have on the drive / what capacity the drive is. ¦ Reisio (talk) 20:02, 15 April 2013 (UTC)
- The simplest route for you would probably be to use an archive manager such as 7-Zip to split the file into 4GB volumes. You could also in the same process compress (with 7-Zip’s “ultra” 7z/LZMA2 compression), which can under certain situations make 8GB of data into 4 or less (although merely storing the data in 4GB volumes will take less time than storing and compressing).
- The trouble with the first two suggestions is they require reformatting the OP's external drive, which would destroy whatever is currently stored on it. And converting it to ext3 would then make it unreadable from Windows XP. Astronaut (talk) 16:40, 16 April 2013 (UTC)
- Windows XP supports NTFS. One of the suggestions is to use the convert to make it NTFS. The BenRG says that this will preserve the data. To be safe, copy the contents of the external drive to another drive before doing the conversion. That sounds like the best thing to me. Bubba73 You talkin' to me? 17:11, 16 April 2013 (UTC)
- This is about the process. Bubba73 You talkin' to me? 17:44, 16 April 2013 (UTC)
advertisement filtering
On a router (mips R3000 big endian) running Linux as its OS (the rootfs is in ext2).I want to block all requests that lead to an add so their are no advertisement on web pages for all devices connected to the router. I don't want to blacklist sites, just advertising content.
I have blacklists that can be converted in any format.
Which program I may use. How I can do this.2A02:8422:1191:6E00:56E6:FCFF:FEDB:2BBA (talk) 20:33, 15 April 2013 (UTC)
- i don't know to much about router blacklists, but if you can have the router drop requests for files with keywords in the title, like "ad" or "buy", that would get rid of some ads. 70.114.248.114 (talk) 21:20, 15 April 2013 (UTC)
- You don't need a router for this; you need a proxy server - which you can often run on the same hardware as the router. squid is the most widely-used free software implementation. Here is the Squid FAQ on implementing an ACL blacklist. You can find numerous other tutorials on the web, including many that provide pre-fabricated content- and domain- blacklists. Nimur (talk) 21:24, 15 April 2013 (UTC)
You didn't answer to the questions.But I'll explain.
In France free as blocked all google's adverts (including AdWords) during some days. As most websites use google services it was nearly meaning blocking all adds.
They used a firmware update and all user's who dowloaded saw all adds gone (for the devices connected to the freebox).They were connected to internet as usual and as they do outside home.
One of the main advantage is blocking adds on totally locked embedded devices (where you can't install anything and you don't have even the right to specify a proxy).You could load pages that couldn't load (because of the ram used by adds).
I want to block all adverts free blocked + non google's ones. I want also that the pages get the same rendering free give to face the lost of the adds.
Now I don't use free as internet provider I don't have a freebox, I don't how they did, and theirs boxes probably run a custom OS.
But I have a router running linux 2.6.30 that you use like a PC (you can do things like installing a web server). It is like a PC except there is no screen and only 1.2 MB of ram is free when the system is running
I log into using ssh or telnet. Routing is configured with an init script and the firewall is done using the iptables command.
The lists are similar to the Easy-list you can find with addblock except they contains lots of more adds. But if there is an alternative solution I am ready to use it, blacklisting was just a suggestion.2A02:8422:1191:6E00:56E6:FCFF:FEDB:2BBA (talk) 23:37, 15 April 2013 (UTC)
- Configure your router to route through your proxy server, and use your proxy server to block, black-list, or replace undesired advertisement content - either per-URL or per-HTML-element. Squid can do both. Then, any devices whose connection is routed through the router will have all their traffic proxied (and therefore, scrubbed of undesired content). Nimur (talk) 00:57, 16 April 2013 (UTC)
You are right, but some computer needs direct access to internet due to some special services. This is the reason I don't have any proxy.
But it may be possible to exclude the machine by mac address, in this case there is not the expected result. In the meant time I don't think the router is enough powerful for squid optimizations.2A02:8422:1191:6E00:56E6:FCFF:FEDB:2BBA (talk) — Preceding unsigned comment added by 62.39.140.158 (talk) 06:59, 16 April 2013 (UTC)
- The following was hatted by the originator as 'Rant unrelated to helping answer the question'. They stuck a reply on my talk page at User talk:Dmcq#reference desk I can't see that there is an excuse on the basis of need in France. Dmcq (talk) 17:45, 17 April 2013 (UTC)
- Why not simply stop using the internet? People have provided you with stuff at the very low cost of letting them try and show you an ad and you want to, well the only real word I have for that is you want to screw them even for that. Perhaps in the future we can have a system whereby you can pay a collection authority for accessing the web without ads rather like the collection agency for money for playing music and then we can have a way of catering for people who will pay otherwise rather than allowing ads to be shown. Would you prefer that? Dmcq (talk) 22:54, 16 April 2013 (UTC)
Google Chrome - is there away to stop websites overriding keyboard shortcuts
I'm used to using certain kayboard shortcuts in Google Chrome - for instance Alt-D to get to the address-bar. Some websites (incl YouTube and Google Drive) take over this shortcut for something else, so it no longer takes me to the address-bar. Is there a way to prevent them doing this (preferably I'd like to be able to select it at individual shortcut level, as it's mainly Alt-D that annoys me)? Thanks, davidprior t/c 07:28, 16 April 2013 (UTC)
- It is probably some scripting (such as Javascript) which is intercepting your keyboard input. You could turn off Javascript, but I doubt that would leave YouTube useable.
- That said, I just tried YouTube in Chrome (with Javascript still on) and Alt-D took me to the address bar. Are you using some special page in YouTube other then just playing a video? Or perhaps you have some plugin at work here. Astronaut (talk) 16:32, 16 April 2013 (UTC)
- Note there is also an HTML attribute accesskey that can add an access key (often a single letter) to any HTML tag, no JavaScript required. The browser decides how to give the user access to the access key. (Internet Explorer decides to use Alt+letter and override any shortcut previously in use. In Opera you press Shift+Esc, letter. You can see how other browsers work in Wikipedia's access key instructions.) However, I don't see any access keys defined on YouTube, and don't want to set up a Google Drive account to test. --Bavi H (talk) 00:46, 17 April 2013 (UTC)
- Davidprior: Can you describe the unwanted action that happens on YouTube or Google Drive when you press Alt+D? This might help us tell how the shortcut is being overridden and help look for a way to prevent it. --Bavi H (talk) 00:46, 17 April 2013 (UTC)
- In a Google Drive spreadsheet it takes me in to the Data menu
- I can't now reproduce it on youtube, so it may only affect certain pages
- Thanks, davidprior t/c 19:35, 17 April 2013 (UTC)
Most resilient data compression?
At their default compression settings, which common data compression format has the most error correction: ZIP, 7Z, RAR, TAR + GZ, TAR + BZ2? --108.84.189.25 (talk) 21:53, 15 April 2013 (UTC)
- None of them has error correction. For some resilience, you want a format (or an option) that disables Solid compression. tar.gz and tar.bz are solid. ZIP is not. 7z is optionally solid. If you care about future proofing, don't use RAR, because RAR is secret proprietary undocumented phooey, and who knows what will support it in 10 or 20 years. But if you really care about resilience, don't use compression at all. Resilience is redundancy, and redundancy and compression are antonyms. 90.212.6.90 (talk) 22:16, 15 April 2013 (UTC)
- The above is correct, however RAR does have the option to create "recovery records" which can correct some data errors. This is not enabled in the default compression settings though. 77.101.52.130 (talk) 23:00, 15 April 2013 (UTC)
- So, in general, if one bit is flipped in the compressed file, the whole thing is lost/unrecoverwable, right? Bubba73 You talkin' to me? 23:30, 15 April 2013 (UTC)
- You should examine parity files, and the par2 format. Shadowjams (talk) 01:30, 16 April 2013 (UTC)
- Disks and CDs have some error correction anyway. The real way to deal with problems if they fail is to have backups kept somewhere else. Dmcq (talk) 09:53, 16 April 2013 (UTC)
- So, in general, if one bit is flipped in the compressed file, the whole thing is lost/unrecoverwable, right? Bubba73 You talkin' to me? 23:30, 15 April 2013 (UTC)
- A file could be corrupted during transmission. Bubba73 You talkin' to me? 17:12, 16 April 2013 (UTC)
- Anything can happen to a file. Error-correction-codes are pretty elaborate, and there is a ton of communication theory that mathematically proves one thing or another about bit-recovery-rate. But every instance of these theories are always predicated on a particular model of data-corruption. If you protect against the wrong type of data-loss, all your work is in vain.
- For example, one can design a data storage medium that is impervious to bit-flip-error for the foreseeable lifetime of the universe, by implementing error-correcting checksums, adding seven-fold redundancy, adding a battery-backup, coating the entire device in thermoplastic resin, and putting it inside a lead box. But, the device containing the file can be dropped out of an airplane and end up at the bottom of the Atlantic Ocean. When this happened to Air France Flight 447's data recorder, all the data-redundancy in the world was insufficient to recover much of the resident data.
- The initial attempt to recover the data was not aided at all by any error-correction checksum, because the device was at the bottom of an ocean. First, a fleet of sonar-equipped ships were required to locate the data. Then, a specialized deep-ocean robot-submarine was required to retrieve the data. Then, the storage medium was scrubbed of salt-water residue; protective layers were cleaned and removed under controlled laboratory conditions... the computer board was baked to remove any remnant moisture; and as soon as it was connected up, the recovered data was flawless - no checksum errors or flipped bits! But, other data on the recovered storage-media (such as the flight's "eQAR" and FCDC computer systems) was lost - and not due to bit-flip errors! In fact, when analyzed under a surface-scanning microscope, the bits were still present. They just were not in any usable form! (There was no non-destructive way to connect the salt-encrusted hard-disk platter to a computer with the right type of software to read the platter - the investigation experiment was terminated).
- Regarding redundancy - the BEA's recommended action for transmitting the data to a remote location for additional redundancy is plagued by practical difficulties: aircraft over the middle of the ocean have poor radio-link, usually over low-bandwidth HF radio, so transmission of data is non-trivial.
- On the other hand, most users of digital data can just "burn a back-up DVD" - which provides enough redundancy to protect the data against "all foreseeable types" of data loss and corruption.
- The point is, it's impossible to describe a suitable "redundancy protocol" unless you have a suitable model of how the data can possibly be lost. All the error-correction-checksums might have been completely unnecessary on Flight 447's data-recorder if every bit of data was stored in an emergency-locator that floated. For this instance, a different model of data-loss (catastrophic data loss due to falling into the ocean) was more probable than random bit flips - and was not sufficiently protected against. Nimur (talk) 18:52, 16 April 2013 (UTC)
- A file could be corrupted during transmission. Bubba73 You talkin' to me? 17:12, 16 April 2013 (UTC)
April 16
WikiCreole to HTML converter
Can someone suggest me a WikiCreole to HTML converter? --Tito Dutta (contact) 12:37, 16 April 2013 (UTC)
- You're basically asking for a WikiCreole engine. You can find a list of engines at http://wiki.wikicreole.org/Engines. Looie496 (talk) 00:57, 17 April 2013 (UTC)
April 17
Arduino clock coding
I'm trying to get a clock working on an Arduino Uno. I've double checked everything but I can't find what I've got wrong. The code I'm using is taken directly from here. For whatever reason though, the hours and minutes displays just count up to 23 and then reset to 00. They increment once per second. And the seconds display is constantly at 00. I have no idea what could be causing this odd behavior. Can anyone tell me what I'm doing wrong? Dismas|(talk) 02:46, 17 April 2013 (UTC)
- I would double check that it is reading the set hour and minutes pins properly. I haven't read through all the code in detail, but it looks like what you see could be caused by the setHour() function triggering every time through the loop. 38.111.64.107 (talk) 12:08, 17 April 2013 (UTC)
For installing Microsoft Security Essentials' latest update, what IS error 0x8004FF80?
I googled it to find unreplied-to topics about the code. Nothing gets me closer to figuring out how to get around the error so that I can successfully install the update.
I have a gut feeling that some malware caused me to no longer be able to find MSE in the first place, so when I went to download it and got the error, apparently the malware is preventing me from updating. Then it seems the malware cuts out all results showing viable solutions, but at least it can't prevent me from asking you on this refdesk. Thank you for your help. --70.179.161.230 (talk) 10:38, 17 April 2013 (UTC)
- You may have some luck with this: [[1]]. I'm not seeing any definitive explanation of the error in my searching either, but a lot of people seem to be looking it up. The 0x8004 shows that it is a failure with a code specific to the component that created the error, so generic error lookup tools don't help. 38.111.64.107 (talk) 12:01, 17 April 2013 (UTC)
Help with Blender and backgrounds
As part of a short film I am working on, I need a scene with animated characters seeming to interact with a real scene, a background that I have filmed myself. I need some way of setting these characters over this background scene and moving them around in exactly the right way at the right time, however I cannot seem to find how to set a moving image as background or to have it render as part of the final output of the program. There are options within the program for this sort of thing, so I know it is possible, yet somehow whatever I try, I can't get the file into the program or set as the background. any idea what I might be doing wrong?
213.104.128.16 (talk) 15:03, 17 April 2013 (UTC)
- Have you Googled for tutorials? E.g. this one came up when I Googled "blender background video." It seems more or less to do what you're asking for, no? With Blender, I find one often has to rely heavily on tutorials, because the documentation is obtuse if not non-existent. --Mr.98 (talk) 15:56, 17 April 2013 (UTC)
Find Raspberry Pi on network
Hi all. I'm try to establish a remote connection between my Raspberry Pi and laptop over a wired network that I am not the administrator of. Running "ip addr" on the Pi suggests a local IP allocation of "10.10.23.128/22". I have tried searching both that particular IP and the range from my laptop using nmap -- the particular IP is down; I find lots of other computers attached to the network over that range, but not the Pi. If I run "ip addr" from my laptop, I get 10.10.23.60/22 and it can find itself at that address (or it seems to, anyhow). Both can connect to the internet fine, so they must both be having no trouble accessing the network. What am I doing wrong? There's probably a really simple answer, but this all worked nicely on a different network that I am the administrator of :/ (It's possible that the administrator of this network is blocking requests somehow, but as I say, I can see other PCs attached to the network.) Thanks in advance, - Jarry1250 [Vacation needed] 19:34, 17 April 2013 (UTC)
- It's possible that the ethernet switch is set to maintain multiple VLANs. It may be doing that based on physical port (network socket on the wall), on MAC address (e.g. untrusted or unknown MAC get put into a "guest" VLAN), or on any number of other reasons the network administrator may have chosen. As you've already determined on your own network, a Raspberry PI running say Debian isn't substantively different from any other Linux machine (its MAC should begin B8:27:EB). You may have to talk to the switch administrator. -- Finlay McWalterჷTalk 19:53, 17 April 2013 (UTC)
- The VLAN by MAC sounds plausible (the Pi's does indeed begin with B8:27:EB), thanks. If there are no other suggestions I guess I'll have to email.. - Jarry1250 [Vacation needed] 20:10, 17 April 2013 (UTC)
- In particular, they may have rules that say "machines on physical ports A,B,C, and D are routers, servers, printers, etc. - so they can send to, and be sent to, by everyone; every other machine doesn't see any traffic other than from A,B,C, and D". That way they can stop normal clients seeing one another at all, so people don't inadvertently advertise services like file sharing to one another, mess the network up by accidentally running their own DHCP server, and one guest machine that's infected by a rootkit which tries to probe the localnet for more victims can't see anything but machines that are properly administered by someone who knows what they're doing. If this is the case, all the machines your nmap scan will report should be these kinds of things, and not someone else's laptop. Filtering by physical port rather than MAC address is more robust (because it can't be spoofed). -- Finlay McWalterჷTalk 20:33, 17 April 2013 (UTC)
- The 128 at the end of the ip is a bit worrying - perhaps it is on another subnet or you have it masked out in your subnet mask? Or perhaps 'over that range' covers this possibility. Dmcq (talk) 20:39, 17 April 2013 (UTC)
- What's special about 128? The /22 part is CIDR notation, and both of these addresses are in the same CIDR subnet. -- Finlay McWalterჷTalk 20:57, 17 April 2013 (UTC)
- Sorry yes I misunderstood. That seems a lot of devices and I was really just saying I would definitely expect the two devices to be on different network switches even if they are trying to make them look like they are all on the same subnet. Dmcq (talk) 00:02, 18 April 2013 (UTC)
- Have come around to that they probably are implementing VLANs as the first responder said. Dmcq (talk) 10:10, 18 April 2013 (UTC)
- What's special about 128? The /22 part is CIDR notation, and both of these addresses are in the same CIDR subnet. -- Finlay McWalterჷTalk 20:57, 17 April 2013 (UTC)
- Have you tried running "/sbin/ifconfig" on the Pi? You don't have to be admin to query ifconfig (but do to make any changes). That should list the address that it has been allocated by DHCP. -- CS Miller (talk) 20:11, 18 April 2013 (UTC)
April 18
STEAM Game install problems
I just tried to install the game "Sniper: Ghost Warrior". I entered the 'key code' etc, was told it was installed (after what seemed like an unusually long wait), but my Steam account itself still says "NOT installed". Shut down PC, re-booted, & logged onto Steam again, but still "... not installed"!
2 days ago I 'installed' the game Homefront, and that also is not working. It appears to be stalled in the middle of an update. Nb. Steam defaults to automatically updating, so as soon as you load a game it starts making large downloads.
In addition I already had Metro 2033 installed, and after playing it since installing Homefront that has also changed to "not installed". It gave me message when starting the game about "needing to store Metro files in another format" or words to that effect, perhaps I clicked on the wrong button!
Is this a common problem with 'Steam'?
Any ideas on what to do? --220 of Borg 03:38, 18 April 2013 (UTC)
- What machine are you using? If it's a Windows PC my first move would be to try uninstalling those games via the Windows control panel, if you can.--Shantavira|feed me 07:10, 18 April 2013 (UTC)
- Yes, Microsoft Windows 7 Home Premium (32 Bit) on a Toshiba laptop (Satellite L750 Model PSK2YA-05210), 4 Gb memory and about 150 Gb free HDD space. Uninstalling is certainly something to try, but then I will have to get on the Internet again to install, and I have not had an internet connection at home since 28 February when my ISP Unwired closed down.
- (my attempts to get a 'Net connection via a 'Dodo' ISP USB mobile internet device is another long tale of woe in itself. The 'gizmo' works on every PC I have tried it on, except mine!)
- Yes, Microsoft Windows 7 Home Premium (32 Bit) on a Toshiba laptop (Satellite L750 Model PSK2YA-05210), 4 Gb memory and about 150 Gb free HDD space. Uninstalling is certainly something to try, but then I will have to get on the Internet again to install, and I have not had an internet connection at home since 28 February when my ISP Unwired closed down.
- /whinge
I have used about 3 Gb (!) of my brothers Internet bandwidth to (so far) for zero result! My experience of installing games needing Steam activation is rapidly losing it's 'novelty'!
I note that it seems some games will not even begin to install if you are not online and logged onto Steam.
/whinge
220 of Borg 11:01, 18 April 2013 (UTC)
- /whinge
- Update: Sniper: Ghost Warrior now says "ready to play!" . Fingers crossed! 220 of Borg 11:03, 18 April 2013 (UTC)
- And 'Sniper' seems to be working! But 'Homefront' needs another 5+ Gb and hours of download to work! 220 of Borg 11:30, 18 April 2013 (UTC)
DOS operating system
I was browsing a local computer store, and was surprised to see that none of the laptops were sold with Windows as the default OS. A small number of laptops had Linux as the OS, but the majority of them were listed with DOS as the OS. As a layperson whose main memories of DOS include a b/w dialogue box that opened when wanting to play computer games in early editions of Windows, DOS to me would seem to be the equivalent of 'no OS'. What exactly would a DOS OS be? Would a person with no programming skills, like me, be able to use it, or would I need to instal a 'proper' OS? V85 (talk) 11:47, 18 April 2013 (UTC)
- It's probably FreeDOS. They don't really anticipate that you'll actually use it, but rather that someone will install a capable modern OS. They're either doing this so they can advertise the machine at a lower price and then add on the cost of whatever Windows OS you want (as a Microsoft Small System Builder, they can probably put on a variety of OEM versions). It's also quite possible that they'd foresee the machines having Linux put on them, but they're not capable of supporting Linux (and don't want all the "this windows program doesn't work" calls it would bring them), so they sell the machine clean and say "caveat installer". -- Finlay McWalterჷTalk 11:57, 18 April 2013 (UTC)
- “caveat installer” is great :) ¦ Reisio (talk) 15:23, 18 April 2013 (UTC)
- Caveat onero ? Is that proper Latin ? StuRat (talk) 16:06, 18 April 2013 (UTC)
- Disk Operating System was an OS; probably MS-DOS. By the time you're working with a DOS window you're now into Windows 3.1 (probably) territory, which is a different OS. Of course people still referred to the window as DOS, but it was a new OS emulating DOS (I'm sure someone could fault me for saying "emulating" here, but i'm speaking generally). Even today with Windows 7 you can pull up a nice black command window that looks an awful lot like DOS. But true DOS... I would be impressed to see someone do something interesting on a modern machine with it running an original version of DOS. Shadowjams (talk) 19:19, 18 April 2013 (UTC)
address manipulation in assembly language
this is a simple instruction in assembly language.
A 1,901 (2, 15)
1 = accumulator 901 = offset 2 = index register 15 = base register
the addresses contained in the three registers are added and the obtained address contains a value which is then added to the contents of register 1.
my question is: why do we have to go through the pain of adding three addresses to get the required address? why not use the required address directly?
P.S. i have just started studying System Programming from John J. Donovan... so, please go easy on the technical stuff. i'm not that tech-savvy. :P — Preceding unsigned comment added by 117.197.252.4 (talk) 14:29, 18 April 2013 (UTC)
- It's generally very desirable for programs to be relocatable, in other words, written in a way that allows them to run correctly even if they are moved to a different place in the computer's memory space. That's what the mechanism you're showing achieves, if I understand it correctly. Looie496 (talk) 14:54, 18 April 2013 (UTC)
- It looks like you're talking about an x86-like processor. The x86 family (at least in non-64-bit mode) has a segmented memory system. That is, by its intrinsic nature, memory addresses are made up of two words, frequently in two seperate registers, that are added together to get the absolute memory address. Note that for x86s, you can't just use any two registers. The segment address (base register) has to come from one of the segment registers (e.g. CS, DS, SS, ES), whereas the offset address can come from any of the general purpose registers. This allows for the relocatability as mentioned above, as all you have to do to move the program around is change the value in CS, DS, SS, ES, etc., as appropriate. - So why the offset? This makes working with aggregate data structures easier. You just have to load the pointer to the beginning of the data structure, and then you can quickly access data members with different offsets, rather than having an extra ADD/SUB instruction manipulating the address, and potentially leaving it in an unknown, varying state in loops and the like. It's extra conveniences like that which make x86s a CISC architechture, rather than a simpler, but more wordy, RISC. -- 71.35.127.8 (talk) 16:37, 18 April 2013 (UTC)
- Allowing just a displacement and a register is done on some machines. This means more instructions are needed in many cases but the RISC argument was that the machine cycles could be shorter. It hasn't worked out that way the extra logic to deal with the possibility of two registers in forming an address sometimes has in general been found to be worth the bother. Plus the possibility of automatically scaling of the index register for the data size is often desirable as well. Dmcq (talk) 17:50, 18 April 2013 (UTC)
Unix command to output specific text

This one should be pretty simple and I'm 90% sure I've seen it before, but it doesn't yield to searching easily. Suppose I want my bash to simply output "Hello." What should I type for this to occur? Presumably, I could also type command "Hello" > file
(where command
is the command I'm looking for) to create a file whose contents are "Hello". What's the command? ± Lenoxus (" *** ") 17:02, 18 April 2013 (UTC)
echo Hello
. There are various options and ways to quote, but that's the basics. --Stephan Schulz (talk) 17:04, 18 April 2013 (UTC)
- Thanks! (Somewhere in my mind I thought it was "parrot" -- I should have just looked up "parrot" in a thesaurus!). The man pages should take me from here. ± Lenoxus (" *** ") 17:25, 18 April 2013 (UTC)
- Not that it will matter much, but FYI
echo
is frequently a shell builtin (type echo
), so the technical authority would behelp echo
. ¦ Reisio (talk) 17:38, 18 April 2013 (UTC)
- Not that it will matter much, but FYI
InterruptedException in java
Hi !
My doubt is on InterruptedException in java .
I am asking my doubt based on sleep method in java.
When we call interrupt on a thread which is in sleep state then InterruptedException is thrown.
Below are my doubts:
1)Imagine that we have called interrupt method on a thread named Thread1,which has come out from a sleep.
Then will Thread1 throws InterruptedException?
2)Imagine that we have called interrupt method on a thread named Thread2,which will go to sleep.
That means now Thread2 is not in sleep state.
Then will Thread2 throws Interrupted exception?
— Preceding unsigned comment added by Me shankara (talk • contribs) 17:53, 18 April 2013 (UTC)
- The sleep stops as soon as the thread is interrupted. An InterruptedException will only be thrown by methods that are documented as able to throw that exception. Otherwise you need to check the interruption flag using isInterrupted(). See [2] and [3]. 38.111.64.107 (talk) 18:47, 18 April 2013 (UTC)
- If an interrupt arrives while a thread is not blocked or sleeping, the thread's interrupt status is set; attempting to block or sleep with that status set immediately (clears the status and) throws an InterruptedException. (The static method Thread.interrupted() clears the status (and returns it), so it's possible to avoid the exception.) --Tardis (talk) 02:08, 19 April 2013 (UTC)
3D glasses for Blu Ray
I am interested in getting the 3D versions of The Hobbit and The Life of Pi for my ASUS gaming computer. I have a 3D set and a 3D compatible player. How do I know what glasses to get, since I see hey sell green/magenta, red/cyan, and polarized? Thanks. μηδείς (talk) 19:20, 18 April 2013 (UTC)
- Most 3DTVs use expensive active shutter style glasses, rather than the cheap polarized types used in cinemas, although there are exceptions. Anaglyph glasses (with different coloured lenses) are used for viewing 3D images on a standard 2D screen, and aren't what you're looking for here. To the best of my knowledge, most active shutter TVs use proprietry glasses, so you would need to buy glasses for the specific manufacturer's TV. What is the make and model of your set? AJCham 19:37, 18 April 2013 (UTC)
- It's whatever glasses your TV manufacture uses. I know that Samsung are active-shutter, and most LG are passive polarized. Do a web search for "<manufacture> 3D glasses" to get suitable manufacture's and third-party glasses. CS Miller (talk) 20:08, 18 April 2013 (UTC)
- Thanks, I understand theresponses, but I have no idea how to determine what type of 3d I have. I have an ASUS computer with an NVIDIA Gforce GTX video card. When I type in 3d on the start search box (I have windows 7) it offers me the option of activating 3d but says nothing about active or passive shutter. What should I be looking for and where? μηδείς (talk) 20:33, 18 April 2013 (UTC)
- Nvidia 3D Vision 87.115.151.155 (talk) 20:35, 18 April 2013 (UTC)
- Thanks. Now I have to decide if I want to spend $150 on the glasses just to see what the 3D looks like. Wonder if Sim City comes in 3D. μηδείς (talk) 21:00, 18 April 2013 (UTC)
- If you do get it, make sure you get the 2.0 model, and the full kit (the USB adapter and a pair of glasses); don't just get the glasses, as you need the USB adapter too (it tells the glasses when to change). Some online reviews give the system reasonably marks, but with a 120Hz (vertical refresh) monitor - your laptop probably has a lower vertical rate (the nvidia app you already have in the control panel will show you), which may be flickery when the glasses effectively half it. 87.115.151.155 (talk) 21:24, 18 April 2013 (UTC)
- How exactly would I find out if I have a 60Hz or 120 Hz display? (I can do it on my Mac and have tried with the PC, but am having no luck.) And if I want three sets of glasses do I purchase two satnd-alone glasses and one with USB? Thanks. μηδείς (talk) 22:11, 18 April 2013 (UTC)
- If you didn't explicitly pay for a high frequency monitor, or a super-expensive gaming system, then you probably don't have one. In the windows control panel: "screen resolution", then "advanced settings", and the vertical frequency is shown in the "monitor" tab (maybe). [That's windows 7, I don't know about other versions exactly]. 87.115.151.155 (talk) 22:21, 18 April 2013 (UTC)
- Thanks. It is 60 Hz. Let me repeat my other question. If I want three sets of glasses so I and two others can watch can I buy two stand alone pairs, or do I have to pay for the full set three times? μηδείς (talk) 00:14, 19 April 2013 (UTC)
- It appears from the product literature that you can use any number of the additional glasses (I see them for sale by themselves, without the USB dongle). But I stress that I've no personal experience of this system, and as someone with whom 3D systems don't agree, they all seem like dim flickery migraine-inducing gimmicks. TinyLittleRobot (talk) 07:38, 19 April 2013 (UTC)
- The above postings by 87.115.151.155 were me - I finally remembered my password TinyLittleRobot (talk) 07:47, 19 April 2013 (UTC)
- Thanks. It is 60 Hz. Let me repeat my other question. If I want three sets of glasses so I and two others can watch can I buy two stand alone pairs, or do I have to pay for the full set three times? μηδείς (talk) 00:14, 19 April 2013 (UTC)
- If you didn't explicitly pay for a high frequency monitor, or a super-expensive gaming system, then you probably don't have one. In the windows control panel: "screen resolution", then "advanced settings", and the vertical frequency is shown in the "monitor" tab (maybe). [That's windows 7, I don't know about other versions exactly]. 87.115.151.155 (talk) 22:21, 18 April 2013 (UTC)
- How exactly would I find out if I have a 60Hz or 120 Hz display? (I can do it on my Mac and have tried with the PC, but am having no luck.) And if I want three sets of glasses do I purchase two satnd-alone glasses and one with USB? Thanks. μηδείς (talk) 22:11, 18 April 2013 (UTC)
- If you do get it, make sure you get the 2.0 model, and the full kit (the USB adapter and a pair of glasses); don't just get the glasses, as you need the USB adapter too (it tells the glasses when to change). Some online reviews give the system reasonably marks, but with a 120Hz (vertical refresh) monitor - your laptop probably has a lower vertical rate (the nvidia app you already have in the control panel will show you), which may be flickery when the glasses effectively half it. 87.115.151.155 (talk) 21:24, 18 April 2013 (UTC)
- Thanks. Now I have to decide if I want to spend $150 on the glasses just to see what the 3D looks like. Wonder if Sim City comes in 3D. μηδείς (talk) 21:00, 18 April 2013 (UTC)
- Nvidia 3D Vision 87.115.151.155 (talk) 20:35, 18 April 2013 (UTC)
- Thanks, I understand theresponses, but I have no idea how to determine what type of 3d I have. I have an ASUS computer with an NVIDIA Gforce GTX video card. When I type in 3d on the start search box (I have windows 7) it offers me the option of activating 3d but says nothing about active or passive shutter. What should I be looking for and where? μηδείς (talk) 20:33, 18 April 2013 (UTC)
- It's whatever glasses your TV manufacture uses. I know that Samsung are active-shutter, and most LG are passive polarized. Do a web search for "<manufacture> 3D glasses" to get suitable manufacture's and third-party glasses. CS Miller (talk) 20:08, 18 April 2013 (UTC)
how elevators talk
I want to know how elevators talk this applies to the us — Preceding unsigned comment added by 75.15.67.222 (talk) 21:14, 18 April 2013 (UTC)
- Elevator control systems usually use one or several programmable logic controllers. These talk together with one another using something like Industrial Ethernet (or one of the proprietary automation protocols listed in that article) or with a simpler system like LonWorks or Ez-LINK. 87.115.151.155 (talk) 21:36, 18 April 2013 (UTC)
- On this topic, is anything known about the "intelligence" of elevators? Specifically in cases where a tall building has multiple elevators, how do they work most efficiently? Ryan Vesey 21:42, 18 April 2013 (UTC)
- A lot of study has been put into this, particularly for very tall buildings. Elevator#Special operating modes lists some of the modes. Elevator companies like to claim tha their controllers for skyscrapers use advanced scheduling algorithms that know the specifics of traffic in that building; some use (or say they do) neural networks or machine learning. As with many real-world scheduling and queueing problems, fairness and efficiency often have to be traded against each other. 87.115.151.155 (talk) 21:48, 18 April 2013 (UTC)
- You might also be asking how elevators talk to people, say when they announce the floor. In this case, a full speech synthesis system isn't required, as it only needs a very small vocabulary. So, the elevator design company can just hire someone with a pleasant voice to say all of the phrases the elevator can say, and record those digitally for later use ("Oh, that must be Otis !"). StuRat (talk) 02:36, 19 April 2013 (UTC)
April 19
captchas
how are the data-bases of images mapped to strings made? (and whats an "op"?) 70.114.248.114 (talk) 02:40, 19 April 2013 (UTC)
- In here an OP is an original poster (or their original post). So, it's you or your question. StuRat (talk) 02:52, 19 April 2013 (UTC)
- Wikipedia's CAPTCHAs are made with mw:Extension:ConfirmEdit. In Internet discussions, "op" means original post or original poster. PrimeHunter (talk) 02:57, 19 April 2013 (UTC)