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March 22

Microsoft Groove

What is the use of Microsoft Grove? --Extra999 (Contact ^me + _contribs) 04:14, 22 March 2010 (UTC)

See Microsoft Groove. I feel the opening paragraph sums it up very well. -- kainaw™ 04:17, 22 March 2010 (UTC)

What are the future prospects for inserting highlights, annotations, and html anchors into other people's websites?

I did a google search for "annotate a website", and I was really excited by this service.

1. Unfortunately, this particular service ("Jump Knowledge") has been discontinued. Do you know of any good alternatives that offer the same services?
2. I think that services like this would revolutionize the work of quoting, paraphrasing, or commenting on other people's work (including in academia, law, of course Wikipedia, and probably everything else). Is it generally understood that services like this will grow in availability and popularity? (Is this something that everyone knew about but me?) If not, what are the obstacles to making services like this succeed?

Cheers, Andrew Gradman ^talk/_WP:Hornbook 07:10, 22 March 2010 (UTC) (editing from an IP address, for complicated reasons, as 207.237.228.236)

• Following up on my own question, I found Web_annotation. This is still a novel idea for me. Please refer me to other resources if you can. Andrew Gradman ^talk/_WP:Hornbook —Preceding unsigned comment added by 207.237.228.236 (talk) 07:25, 22 March 2010 (UTC)

It's inevitable. ¦ Reisio (talk) 08:41, 22 March 2010 (UTC)

There are not any real technical challenges, other than the fact that if you want people to be able to see annotations easily, you have to convince a lot of people to all go to the same services (or find some way to collate them). But that sort of thing works it out pretty straightforwardly.

Practically, if it really took off you'd need to have some way to sort between potential annotators. I presume it would be something like Twitter or podcasts where you subscribe to particular people. One can imagine how much of a zoo it would get for popular sites. (Just take a look at the cesspool which is the comments section on any popular news site.)

Legally, I suspect it would count as creating a derivative work. In some countries that could raise copyright issues. How that would play out, I'm not sure. I suspect there would be a court case somewhere down the line.

Will it be popular? Who can say. I kind of suspect not so much. Link sites (e.g. digg) work well because they provide a narrow view at a wide spectrum of pages. Blogs work well because they allow you to connect content with commentary but again through a narrow view. Having each page on the web have potential annotations means that unless you have some narrow way to point you to pages (e.g. a blog), the odds of you hitting a page that your favorite commentator has commented on is probably low. And I guess I wonder how interesting it would actually be in practice, how much different it is that the existing experience where people who want to comment on a web page just create a new web page (e.g. a blog) about it. --Mr.98 (talk) 13:39, 22 March 2010 (UTC)

No, it'll definitely be popular eventually. You know how people say "go to domain.tld and click on FOO and right there in the second paragraph, the fourth line, look at that!"? Instead you'll just get a link that automatically highlights the relevant bit/s. It's simple to do now, it's just a matter of someone thinking up some stupid misspelt "web 2.0" name for people to associate with it. ¦ Reisio (talk) 16:32, 22 March 2010 (UTC)

Do people say that on a regular basis? I don't see that as actually being something that is majorly in demand. (Again, technically it is not hard to do, and has not been for ages.) I don't think it will take off unless it finds some way to harness human vanity/exhibitionism/voyeurism, which all of the really successful Web 2.0 applications (Facebook, Twitter, Wikipedia, blogging, etc.) have managed to do. Just being able to highlight stuff... it's a cute trick, I guess, but wildly popular? Maybe I'm just an old fogie here, but I am dubious. It don't see it filling a particularly big need (something not already filled by link aggregators and blogs), and don't see it catering to any basic human impulses (vanity, etc.). But who can predict the future? I probably wouldn't have thought that "microblogging" would have been popular, either, had someone pitched it. --Mr.98 (talk) 23:09, 22 March 2010 (UTC)

• Thanks, these are great answers.
• Mr.98, I understand you to be saying that when annotations consist of marginal notes, they might add more chaos than value. I agree with that. I also agree with Reisio that the real value proposition is the ability to insert html anchors and to highlight text. (Just think about how much easier it would make our work on Wikipedia!!)
• Those two steps would make the "annotation" function obsolete, because the material that would have gone into those "annotations" could just be put into the body text of the external document (e.g. wikipedia article) that employs the link to the html anchor. One could still aggregate those annotations alongside the original document via a Google search of the entire web for hyperlinks containing that anchor (sort of like putting a "what links here" button into the document.)
• That makes me excited, because it means that really good "web annotation" can be done on the cheap! Andrew Gradman ^talk/_WP:Hornbook 19:48, 22 March 2010 (UTC) —Preceding unsigned comment added by 128.59.179.216 (talk)

lib to java class/.net il ?!

Is it (at least theoritically) possible to convert .lib/.o/.so/.dll files to java (JVM/.class) or .NET (CLR/il) ?! --V4vijayakumar (talk) 09:50, 22 March 2010 (UTC)

It's theoretically possible (see Turing completeness), but that doesn't mean it's easy.

What problem are you trying to solve? Are you wanting to call library functions in a DLL (or .so library in Linux) from Java or .NET? This can be done in Java using the Java Native Interface[1], and while I'm less experienced with .NET, it should be even easier from C# - see e.g.[2] --Normansmithy (talk) 12:20, 22 March 2010 (UTC)

If it was originally compiled from .NET, it's almost certainly still in IL, in which case .NET Reflector makes things very, very easy. —Korath (Talk) 14:45, 22 March 2010 (UTC)

How can I find out my first router's upstream IP when I'm behind several levels of NAT?

Situation:

(Internet)---(final NAT router)---(possibly more NAT routers)===(first NAT router)---(Linux box)

How can I find out what the IP of the NAT router in the network marked "===" is, when I'm root on the Linux box?

The Problem(s):

• determining the IP should be possible in a non-interactive, scripted way
• the router's GUI is inaccessible (Web only, requires User/Password, and some fancy JavaScript - Linux box is text only, and wget doesn't have a JS interpreter)
• changing to another router brand/model is not possible

Finding out the public IP of the final NAT router would be easy (wget http://whatsmyip.de/ or a similar service and parse the result) but so far I haven't found a way to figure out the outside IP of my first NAT router. Traceroute only shows the internal IP known to the Linux box as its gateway, and the IP the next upstream NAT router has in the "===" network. Is there something like a "boomerang packet" that I could send to the next upstream NAT router and that would log and return all the IP addresses it has passed on its way? After all, on its way back, it would see the outside IP of my first NAT router, as it has to go back there... -- 78.43.60.58 (talk) 10:43, 22 March 2010 (UTC)

Addendum: ping -R some.ip.he.re should log the reverse route, but doesn't - one router flat out refuses to pass ping packets with a set RR flag, the other treats them like ordinary pings. :-( -- 78.43.60.58 (talk) 12:26, 22 March 2010 (UTC)

I think you'll need to leverage a protocol that works at the application layer because otherwise your NAT (which is doing some sort of inspection) is almost certainly going to rewrite the IP headers completely. The ping manual confirms what you say about -R, that it's not often supported.

I've got a few ideas, none of which are certain to work. First, you might try looking around for other protocols that could return the same information. If the NAT uses SSDP or some other management protocols, they might leak information about IPs.

The second one is less elegant. If the potential address range is small enough you may be able to guess at a proper IP, and then confirm through trial and error. Traceroute should tell you the gateways along the way, and from there you might be able to guess at a range of addresses. Then you could send them ICMP packets or something else you know will be returned, preferably with some sort of random number returned in each. This won't work if your NAT won't forward local addresses (or act generally weird when trying to do multiple-subnet setups, something I've seen on home routers). I may well have missed some obvious flaw here too, but maybe that gives you some idea of a place to start. Shadowjams (talk) 16:54, 23 March 2010 (UTC)

I left out a crucial part of the second one. The return address on the packets you send will need to be spoofed to the guess address. Then, you're going to need a way to see that packet. Two ways you could do that. If you can see the outer range of the second one, then that's easy, but then you probably already know the IP anyway. Second, you could try to do something similar to nmap's zombie scan, where it looks for a packet by checking sequence numbers. So send packet to the second gateway address with a spoofed return address of your guess. Note the sequence number of the second gateway. Then send another, noting the sequence again. If the sequence increments in between then it may have received a RST from the IP you're trying to figure out.

I'm assuming you own the relevant parts of the network too. I wouldn't advise sending spoofed packets onto other people's networks. In addition, there are a dozen things that could go wrong with this, I'm really thinking off the top of my head here. Shadowjams (talk) 17:08, 23 March 2010 (UTC)

Here's the nmap description of idlescan (zombie). You might also check out hping. Shadowjams (talk) 17:10, 23 March 2010 (UTC)

Spell check's algorithm

If you have a short text (say 4,000 words) and a list of words in a dictionary (250,000), does the spell check goes through the list of 1,000 words and the whole dictionary? That would mean 1.000,000,000 actions. Is that too much for a computer? Is there a more practical solution to optimize this thing? --ProteanEd (talk) 11:53, 22 March 2010 (UTC)

Simply deciding if a word is in the dictionary or not can be done in constant time (that is, it takes about the same amount of time if there's one word in the dictionary or a million) with a hash table. In this case, a hash table would be a big array, with the dictionary words scattered throughout it in such a manner that the programmer knows for a given word, where that word would be, if it were in the hash table at all. There's a bit of extra complexity (what if two words wind up being in the same place?), but hash tables can make spell-checking quite fast.

Now, making spelling suggestions is harder, and I don't know off the top of my head how it's done. Since the spellchecker needs to find words that are close to the word that it is looking for, it needs to do some clever approximate string matching to run fast. Simply running through a quarter million words and calculating the edit distance to all of them from the misspelled word would probably work on modern hardware, but there would be a noticeable pause, so they don't do it that way. Paul Stansifer 12:22, 22 March 2010 (UTC)

(edit conflict) Sort your dictionary in alphabetical order and use a binary search? Or index your dictionary. There's certainly no need to check each word in your text against all 250,000 words in the dictionary: you just need to know where the word would be in the dictionary if it existed, and then check if it is there. If you want to find a word in a paper dictionary you wouldn't start with page 1 and read all the words on it, then try page 2... --Normansmithy (talk) 12:25, 22 March 2010 (UTC)

You probably don't want to use a sorted list of words directly; a hash table's faster for spellchecking, and alphabetical order's only good for finding suggestions when the error's got a few correct letters to the left of it. (in particular, "the" and "teh" have a whole lot of words between them, and you're out of luck if you type a "c" instead of a "v" at the beginning of a word). But alphabetical order is the best that we can manage for "manual" spell-check. Paul Stansifer 01:55, 23 March 2010 (UTC)

To quickly search a word list, I'd have an alphabetically sorted list, indexed for the first few letters, then use a binary search beyond that. So, let's say I was looking up FREEMARTIN, I'd find the index offsets for FRE and FRF, then do a binary search between those values.

As for suggesting corrections, having a list of common misspellings of words would help here. If not, there could be a list of common phoneme errors, like "f" in place of "ph". You might also want to include keyboard errors. For example, a "b" in place of a "v" is likely, since they are adjacent on a QWERTY keyboard. StuRat (talk) 13:30, 22 March 2010 (UTC)

Phonic matching is based heavily on soundex. It takes constant time to calculate soundex (just replace the letters with numbers) and then constant time to lookup the soundex code in a table. The "definition" of the soundex code will be the words that match the soundex code. -- kainaw™ 13:35, 22 March 2010 (UTC)

Soundex works great when it's a genuine spelling error (like if you wrote "foneem" instead of "phoneme") - but it's not so great for typos ("ghoneme", "hponeme", "phoeme", etc). For those things, you need to look for words with one letter difference, words with swapped pairs of letters, words with extra letters and words with missing letters. For that, a binary search for likely candidates works best. You can also use Hamming distances to find the most similar words from your dictionary. But the time it takes to do spell checks is mostly in the time it takes for verify the correct words because (generally) the vast majority are spelled correctly...and for that a simple tree search or perhaps a hash table lookup is the fastest. SteveBaker (talk) 04:04, 23 March 2010 (UTC)

A fairly obvious data structure for this is a trie. For large dictionaries of relatively short keys its an excellent data structure, and not as messy and unorganized as a hash table. In fact, one can probably use a trie to find some classes of spelling errors. --Stephan Schulz (talk) 10:36, 24 March 2010 (UTC)

What is Smart Business?

I was watching Undercover Boss on Sunday night and they showed the CEO on the cover of a magazine called Smart Business? Does anyone know where I can get a copy of this magazine and what they're all about? —Preceding unsigned comment added by Markus37627 (talk • contribs) 15:01, 22 March 2010 (UTC)

I never heard of this magazine/newsletter, but here is their website. "Smart Business magazine subscriptions Smart Business is offered at no cost to qualified recipients. To request a subscription or to update your subscription information call our circulation department at 866-820-0329." Nimur (talk) 15:24, 22 March 2010 (UTC)

Linux, Multiple Monitors and CLI/Grub

Hi everyone,

An interesting conundrum: I've got an old laptop with no screen (so it's basically a thick keyboard), that I'm using as a server. I use it by plugging a monitor onto the external port. This works fine for the BIOS, Windows, and most of Ubuntu 9.10.

However, I can't use GRUB or the CLI. I don't ever see GRUB, and if I do ctrl-alt-f1 or gdm stop, the external screen goes blank (or freezes) and that's it.

I think this is because they're not outputting to the right screen?

This is a bit of a pain, as now that I've got everything set up, I'd like to be able to boot without gnome to minimise memory waste. I can always ssh after startup and turn off gdm that way, but it's a bit of a pain (and a bit risky) to have no way of controlling GRUB etc...

Does anyone have any clues as to how this could be solved? Is there a way of telling the CLI to "play" on both monitors?

Cheers, 213.71.21.203 (talk) 15:18, 22 March 2010 (UTC)

Check xorg.conf and make sure it is mirroring the screens, not spanning desktops. If it mirrors the screens, the same thing will show up on both screens. Exactly what it should have depends on the video controller in the laptop. -- kainaw™ 15:40, 22 March 2010 (UTC)

Sorry, I wasn't clear enough. This isn't a problem with anything X and above, all that works fine (Ubuntu even has a handy little tool for spanning/mirroring etc now, nice addition). It's only a problem when switching off X (switch to command line only) or using GRUB. So I don't think xorg.conf would help? Then again, maybe I'm mistaken. 213.71.21.203 (talk) 15:44, 22 March 2010 (UTC)

If it is a true CLI and not a "fancy" one with X running, then editing xorg.conf will not help. All of my full-size machines put the CLI on all screens. Your laptop can override that. I have one that does. I have to press Fn-4 to make it put screen output to external. -- kainaw™ 15:47, 22 March 2010 (UTC)

Give that man a banana! I never thoughtof trying to force it at a laptop level. I'll have a look tonight. Thanks, 213.71.21.203 (talk) 15:49, 22 March 2010 (UTC)

"Give that man a banana!" - I think this is an appreciation. which part of world you are from; which language you speak ? --V4vijayakumar (talk) 04:11, 23 March 2010 (UTC)

graph

Can I draw a graph taking values of (x,y)in fortran 90. This program is possible.Supriyochowdhury (talk) 15:47, 22 March 2010 (UTC)

Sure, in many ways:

1) Drawing it using ASCII characters is simple, like so:

    ^
  2 |    * *
  1 |* *   
    +------->
     1 2 3 4

2) Create a graphics format pic, like JPEG or GIF or BMP. This is a lot more work. There are a few human readable bitmap formats, that tend to make huge files, but most are in a binary formats that're more difficult to edit. A system command can then be issued to display the pic, using something like MS Paint.

3) There may be ways to make a graphic display directly in Windows or Linux from Fortran commands, without first creating a file, but I don't know of any, offhand. StuRat (talk) 16:00, 22 March 2010 (UTC)

Try pgplot. 213.71.21.203 (talk) 16:06, 22 March 2010 (UTC)

A major weakness of FORTRAN is its inability to easily generate graphical interfaces, including general purpose plots. Consider outputting your data in a tab-delimited format and piping the output to a graph program like Gnuplot. Nimur (talk) 16:17, 22 March 2010 (UTC)

fortran

what is the quickwin application and standard graphics application in fortran 90 software.Supriyochowdhury (talk) 18:09, 22 March 2010 (UTC)

See QuickWin. As for a standard graphics library for Fortran, I haven't ever seen one. The standard is console output. There are many graphics libraries available for it, but they are not "standard". -- kainaw™ 20:04, 22 March 2010 (UTC)

Quantum computing

I've read the Quantum computer article but there are still some questions I'd like to ask please. 1) How much faster than a conventional computer will a quantum computer be? 2) Despite what the article says about qbits, will quantum computers still be working with conventional logic overlaid on top of the underlying qbit logic, or are there radically different 'magical' things they can do but which conventional computers cannot do? 3) Will a quantum computer ever be the same size and usage as as a home desktop computer or does it need an engineeering plant attached to supply -273 degree C temperatures? 4) How will the quantum part interface with a keyboard and display? Thanks 78.149.193.98 (talk) 20:33, 22 March 2010 (UTC)

1. It won't be faster (or at least, that won't be a function of using qbits), it can simply compute a whole bunch of answers at once in such a way that the "correct" answer drops out at the end.
2. From the lede of the article, it can use certain algorithms that rely on nigh infinite parallelism, but it's still a computer. No magic allowed.
3. Can't predict the future here. It all depends on what technological advances allow us to do.
4. It's not magic. You'd program it in a way similar to programming normal computers. It would likely require a regular CPU to define the problems to it; keyboards and displays simply take input and provide output, quantum really doesn't enter into the equation.

—ShadowRanger ^(talk|stalk) 21:16, 22 March 2010 (UTC)

"It can simply compute a whole bunch of answers at once in such a way that the "correct" answer drops out at the end." Could it be explained how that is done please? 92.24.91.12 (talk) 23:54, 22 March 2010 (UTC)

(1) basically means "faster, but only for some problems". It's a similar problem to parallel computing: if you can break the problem down in a certain way, you can get the result faster as if there were a lot of computers working on it at once (in the parallel computing case (like in your graphics card), this is literally true, but in the quantum computing case, it's not. Regarding (3) and (4), it's probably best to read the "computer" in "quantum computer" not as "personal computer", but in the general sense, as a computational device. Unless the technology turns out to be cheap to manufacture, and consumers tend to want to factor lots of large numbers (you never know!), there's not too much reason to expect to see quantum coprocessors showing up in PCs. Paul Stansifer 02:10, 23 March 2010 (UTC)

Part of the problem is that they'll only be faster for particular classes of highly parallelizable algorithms. It's highly likely that they'd be exceedingly slow for algorithms that require serial processing. Hence, it's most likely that these gizmo's would be highly specialised "co-processors" that you'd hook up to a completely normal PC which would run the operating system, drive the peripherals, etc. For example, it's hard to imagine how you'd use a quantum computer to render graphics for a computer game and it certainly won't help with surfing the web or doing your taxes. But it might be just the thing you'd want for a chess playing computer because it could test all possible moves in one step and looking hundreds of moves ahead might well turn out to be child's play - that would be a truly astounding thing. IMHO, these things will be rare, temperamental and used mostly for scientific computing, cracking encryption, weather forecasting, that kind of thing. I doubt they'll be found in the home or office for a very long time. SteveBaker (talk) 03:48, 23 March 2010 (UTC)

I wonder if someone will come up with a 'quantum coprocessor' for parallelism. Highly unlikely, given the evolutionary architecture... but with enough innovation, anything's possible. Doubting they will be in the home reminds me of the IBM chairman who said that there would be a need for about 5 computers worldwide. I can think of many tasks being made parallel - for example booting up and checking a driver list for hardware changes - if all checks/IOs are done at once, we have instant boot up. Sorting large lists in parallel, compression/decompression of parallel streams then merging the results, buffering, searching caches, virus checks, etc. - many serial tasks can be done or converted to parallel. These tasks could be sent to the "quo-processor" while other serial tasks continued normally, until a point in the future when all serial tasks have algorithms to run in parallel, including rendering graphics. Sandman30s (talk) 12:49, 23 March 2010 (UTC)

But I/O won't benefit from parallelism; quantum computing won't do anything about, say, bus contention (barring some major development I can't imagine). Most tasks that involve a large amount of data are I/O-bound in the first place. Even tasks that are traditionally thought of as compute-bound, like playing chess, might become bound by memory bandwidth if the CPU becomes faster. See Non-Uniform Memory Access for work on the memory bandwidth problem. Paul Stansifer 14:23, 23 March 2010 (UTC)

Who's to say, at this early stage, that qubit storage won't happen in some revolutionary way as well? Traditional IO might be as far removed as the LP is to the USB stick. Boundaries between memory and IO will become blurred as quantum storage media are able to hold exabytes and higher. Imagine being able to store (optical or other) bits at the subatomic level. This will most definitely support parallelism at a grand scale. Sandman30s (talk) 06:22, 24 March 2010 (UTC)

The quantum computer article is pretty good in some ways, but it understates the amount of uncertainty over whether a nontrivial quantum computer can be built at all, even in theory. "Nontrivial" doesn't mean quantum megabits or terabits, it means anything more than a dozen or so quantum bits. You might like Scott Aaronson's lecture notes starting here if you want to learn a bit more about the topic. 66.127.52.47 (talk) 15:24, 23 March 2010 (UTC)

March 23

World Book Cyclo-Teacher Learning Aid

Around 1976, World Book Encyclopedia published a "Wheel of Learning" accessory with encyclopedia sets, which contained a packet of disk-shaped cards which were placed in a mechanical computer capable of showing a question in a window, and if my memory serves correctly, scoring the series of multiple choice questions shown through that window. I can only find a single passing reference to the Wheel of Learning on the web. Can anyone find a description of the scoring capabilities of the machine, or a photograph? Thank you. 99.56.137.254 (talk) 07:28, 23 March 2010 (UTC)

I had a 1967 or 1968 complete World Book set, and I don't remember any such accessory. (It sounds like something I definitely would have remembered). At least this puts a lower-bound on the year they introduced it... I haven't found any information via a cursory web search, but I wonder if you could contact World Book directly to request information. Alternately, you could check used-book and online auction sites to see if anyone is selling one, and contact the seller. Nimur (talk) 14:46, 23 March 2010 (UTC)

I remember it. It was a flat plastic beige box about 18". It was hinged on one side and you opened it an placed a large paper disc with the questions on a spindle, then the answer disc on top. There was a spring loaded trigger to rotate the wheel. It wasn't a computer, just a fancy sort of flash card. We proabably go our WBE set around 1972— they had the off-white covers. ---— Gadget850 (Ed) ^talk 21:50, 23 March 2010 (UTC)

Found it! It was the Cyclo-Teacher Learning Aid. Here is a photo.[3] We also had the Childcraft series— Snopes should use it as a source for urban legends. ---— Gadget850 (Ed) ^talk 22:33, 23 March 2010 (UTC)

Here is a 1966 ad.[4] I remember the salesman coming to the house— I can't pin it down, but it had to be between 1963 and 1974. WBE + Childcraft + the Cyclo-Teacher = $393.15. Big money when a dollar would buy a glass vinegar jug of gas for the mower and a popsicle at the Esso station. ---— Gadget850 (Ed) ^talk 22:59, 23 March 2010 (UTC)

Excellent! Higher-resolution picture, and a detail of the wheel inserts.

I remember now, the scoring usually wasn't automatic, but an answer would appear along with the answer you wrote for the previous question when you advanced to the next question, and the oval area was available to write in your answer's score. Am I correct in remembering that the 1976-era version had some kind of a digital counter to keep track of the score? Also, am I imagining this or was there also a punch-card track for multiple choice questions somewhere on the wheels? The more I think about this, the more it feels like I am remembering from imagination, so I'm very curious to know whether someone else remembers a punch card system for multiple choice scoring. Web searching with the correct name of the device (thanks to Gadget850!) leads me to believe that the memory may be entirely from my imagination. I really wanted it to be true, and I still do so much it almost seems real. 99.56.136.197 (talk) 15:18, 24 March 2010 (UTC)

Lyrics display

I know there are plug-ins that can display lyrics for a song by downloading them from the internet, but are there any plug-ins or options in Winamp that enables a person to view the lyrics that are stored as metadata in the .mp3 file itself? Thanks in advance. 117.194.226.40 (talk) 12:30, 23 March 2010 (UTC)

WinAMP Plugin Search found 25 "lyrics"-related plugins. I haven't used any of these and have no specific recommendations. However, I do know that WinAMP does have built-in display for lyrics that are stored in MIDI files, though that interface is very clunky. I was not even aware that MIDI files could store lyric information until I started getting these irritating popup windows out of WinAMP. Nimur (talk) 16:12, 23 March 2010 (UTC)

digital age classroom

what is a digital age classroom? —Preceding unsigned comment added by 117.99.44.25 (talk) 16:19, 23 March 2010 (UTC)

A classroom in the digital age? I'm not sure it has a precise definition. It probably means that the classroom uses computing as part of its general instruction. I would imagine this would range from taking attendance on the computer screen (which they did even when I was in high school, over a decade ago) to the regular use of the internet in assignments, communication with students, learning, etc. --Mr.98 (talk) 16:25, 23 March 2010 (UTC)

To me, the use of ebooks is one of the most obvious benefits for the classroom, eliminating the need for students to carry heavy and expensive books around. (Not finding a booger in your book from last year is a nice bonus.) StuRat (talk) 16:32, 23 March 2010 (UTC)

Maybe if you spent more time studying and less time picking your nose, you would have moved on to the next grade and wouldn't still be using your books from last year ;) NByz (talk) 03:25, 24 March 2010 (UTC)

It is just a buzzword for having computers in the classroom. It means nothing about how they are used or how effective they are. -- kainaw™ 18:35, 23 March 2010 (UTC)

Verifiable donations to a ACLU/EFF/Wikimedia/Free Software Foundation sort of organization

I want to find a charity that takes online donations in such a way that I, a third party, verify the donation was made (with the permission of the donor, of course).

Let me back up.

Like lots of people, I wrote a little tiny nothing piece of software for my own needs. When I was done, I threw it up on a website, gpled it, and called it good. But except for me, end users are generally non-programmers, so even though the improvements are simple and quick for me, they're out of reach for my users. So even though my one-time need for the program is over, I still try to make the requested changes to improve it when I have time.

But as the program is evolving, more and more requests are coming from people using the software for a business. I don't mind doing these changes, but I certainly don't enjoy fulfilling these sorts of requests as much-- because I'm basically volunteering to be an unpaid employee of a corporation.

What I would like to do is use this as a fundraising opportunity for some charity that I would be proud to help out. I think this would be a lovely solution-- The requesters gets the new features they want , I get to know my time is valued and I'm not being used, the charity gets money to make the world a better place, and everyone gets slightly a slightly better tiny nothing piece of software.

But, to pull it off, I need some way to verify that the requester has made a donation of x dollars to the charity. All aspects of the donation and verification need to happen online-- for ever postage stamp required, I bet I'd lose half my requester.

It needs to be "Click here to donate" button, and then I need to be able to verify the donation as soon as possible thereafter.

Is there anybody who might have such verification system and might also be A Force of Good? I listed the geek liberties groups, but really almost anything non-evil would work. Given the sums and the geography, I don't think "tax writeoffs" are going to be a concern, so it doesn't really matter whether it's a technical charitable donation or not. Just needs to be good, take online donations, and verify them.

Any suggestions for how I could go about finding such a thing? -CreedShandor —Preceding unsigned comment added by CreedShandor (talk • contribs) 18:36, 23 March 2010 (UTC)

Justgiving (UK based - they also have a US based page called First Giving) exists to do just this as far as I can tell, however they are a for-profit company and take 5% of donations before giving it to the charity, so it depends whether that bothers you. Most people use it to raise sponsership for a specific event, but I beleive you can use it long-term as well (one group I found uses it to take donations for an ebook). Equisetum (talk) 18:59, 23 March 2010 (UTC)

I don't know of one that's actually up and running (I hadn't heard of First Giving before) but I'd heard such proposals in relation to anti-spam protocols. Basically you'd make a verifiable donation to a charity of your choice and then anyone who verified the donation could choose to give you some digital cash tokens; then anyone else into spam suppression could recognize tokens from trusted issuers (sort of like OpenID). In your case it's probably simpler to just ask the change requester to pay you directly, or connect up them up to a bounty organizer so they can find someone else to make the change. 66.127.52.47 (talk) 19:18, 23 March 2010 (UTC)

You could register as a "provider" at http://www.fiverr.com, and say "I will write an upgrade to _____ for $5". They have the architecture already in place to collect and remit payments, and with a sufficiently "obscure" tagline, you probably wouldn't get bombarded with requests. (The site keeps $1, you get $4, and you can donate it to whomever you wish.)

Not exactly what you were looking for, but heading in a good direction -- and maybe close enough? DaHorsesMouth (talk) 22:23, 23 March 2010 (UTC)

Mount a laptop hard drive in a desktop?

Hello! My laptop (for all intents and purposes) died a few days ago; whenever I turn it on, all I see is a gray screen, not even the POST or any way of accessing the BIOS (and seeing what I'm doing), but the CPU light keeps flashing, the fan is running, and it does seem that the insides are functional. When I tried booting from a Linux live CD, I could hear the CD drive spinning and the CPU working, but no visual feedback. Anyway, my friend has been generous enough to let me open up his desktop computer and install my laptop's hard drive so I take off all my important files, but I don't know if this is even possible. A google search seems to indicate it can be done, but requires some extra hardware. Both the laptop and the desktop are made by HP, both running Windows Vista (but desktop is 32-bit and laptop is 64-bit, but that shouldn't make a difference). What's the easiest and cheapest way to do this (assuming the problem isn't the hard drive), for someone who has little hardware experience but has seen someone install an internal hard drive? Thank you for the help, or any suggestions about what's going on with my laptop, but I imagine it's one of those things a professional has to play around with for a while to fix. Thanks!--el Aprel (^facta-_facienda) 21:19, 23 March 2010 (UTC)

Presuming you just want to recover the data and not leave it installed. You can get a SATA/2.5PATA/3.5PATA to USB adapter on eBay for ~$5. The downside is that they ship from Hong Kong and take a few weeks. You can find enclosures at Radio Shack and the like. Ensure you know whether you have a SATA or PATA (IDE) interface. ---— Gadget850 (Ed) ^talk 21:36, 23 March 2010 (UTC)

If it's an IDE drive, you need something like this (I searched for "laptop IDE converter"). If its a SATA drive then it should just work. Installing it should not be difficult - the only thing you might need to do is to make sure that the desktop will still boot to its own internal disk, rather than the new one (this is configured in the BIOS, and is almost certainly already set up the way you want). -- Finlay McWalter • Talk 21:40, 23 March 2010 (UTC)

Sounds like just your screen as died, in which case you can hook your laptop up to an external screen. Easiest would then be to get (or borrow) an external HDD to which you can copy all your data.213.160.108.26 (talk) 22:10, 23 March 2010 (UTC)

Just to synthesize a bit of the above: hard drives are just hard drives, but they have different pins that speak different languages. What you need to do is find out whether your laptop hard drive is SATA or PATA or IDE, and then figure out whether the desktop is SATA or PATA or IDE. If they are the same then it is no problem other than removing the hard drive from the laptop and plugging it in as a "slave" to the desktop (which, depending on the model, might be a tough job -- plugging things into desktops is easy but removing parts from laptops can be hard depending on how compactly they are engineered... look online for a tutorial for your model if you can, and keep track of the screws!). If they are not the same then you will need something that will let you mount the laptop drive, like the SATA to USB connector, or an external hard drive enclosure. You can look up whether it is SATA or IDE or etc. by just Googling the model numbers—you should be able to find technical specs about the hard drives. --Mr.98 (talk) 23:38, 23 March 2010 (UTC)

Just for the record: 213 said that the monitor is broken- Though it also may be the video controller. Before you open it up, plug it into an external monitor and see if it works. Otherwise, Mr.98's summary should hold you in good stead. Mxvxnyxvxn (talk) 18:15, 24 March 2010 (UTC)

Thank you all for the information. Your help has certainly made this situation more manageable.--el Aprel (^facta-_facienda) 23:22, 24 March 2010 (UTC)

March 24

Is there a way to edit the html of a page while I'm viewing it?

Sometimes a page loads on my screen and I really need to make a small change (I don't like the width of the columns, or I want to highlight certain words, or something). The changes don't have to be permanent. Is there a way to make them while I'm viewing the page? If the page has webforms (e.g., a Wikipedia edit page), will those still work? 207.237.228.236 (talk) 00:14, 24 March 2010 (UTC)

Yes, Firebug (web development) does exactly this. You can edit the HTML of a specific tag (either of a leaf or a non-leaf) and the change shows in real time as you're typing. You can do the same for CSS (both in stylesheets and inline). The changes are indeed not permanent (they're overwritten on the next reload) but you can save the changed page. At the risk of sounding like a breathy fanboi, Firebug does all kinds of most excellent things for the web developer, and is in general pretty all-round fabtabulous. -- Finlay McWalter • Talk 00:45, 24 March 2010 (UTC)

Wow, this is a superb product. Thank you! 207.237.228.236 (talk) 01:19, 24 March 2010 (UTC)

Internet Explorer 8 does this as well. It's already built in, just hit F12 and the developer tools will load up. ZX81 ^talk 01:55, 24 March 2010 (UTC)

I type JavaScript into the address bar to edit web pages. You replace the web page address with code like this:

Make the page your viewing editable

javascript:document.body.contentEditable='true';document.designMode='on'; void 0

Go to Google images and run this to rotate images:

Rotate images on a page around

javascript:R=0; x1=.1; y1=.05; x2=.25; y2=.24; x3=1.6; y3=.24; x4=300; y4=200; x5=300; y5=200; DI=document.images; DIL=DI.length; function A(){for(i=0; i-DIL; i++){DIS=DI[ i ].style; DIS.position= 'absolute'; DIS.left=Math.sin (R*x1+i*x2+x3) *x4+x5; DIS.top=Math.cos (R*y1+i*y2+y3) *y4+y5}R++} setInterval ('A()',5); void(0);

And here's one I came up with myself. It blanks out all flash movies on a page:

javascript:for(i=0; i<document.getElementsByTagName("object").length; i++){document.getElementsByTagName("object")[i].LoadMovie(0, "f")}

--Chmod 777 (talk) 02:03, 24 March 2010 (UTC)

Yes, Firebug is great for JS debugging and small edits like deleting some obnoxious box in a page. If you want to permanently associate editing scripts with particular web pages, you want GreaseMonkey or for ad blocking, AdBlock Plus. If you just want to mess with Wikipedia pages for your own viewing, enroll an account and set up a customized WP:SKIN which is a javascript file called "monobook.js". 66.127.52.47 (talk) 04:17, 24 March 2010 (UTC)

Thanks, everyone, for the generous answers!!! I particularly am glad I learned about Firebug and also about all the cool things that I can do with javascript in my address bar. 207.237.228.236 (talk) 07:27, 26 March 2010 (UTC)

Looking for win 32 version of Apache httpd 2.0.64-dev

Help! I have Apache 2.0.59 running on windows server 2003. There is a vulnerability (mod_isapi module unload flaw CVE-2010-0425) which I need to patch for.

When I looked at the Apache website (http://httpd.apache.org/security/vulnerabilities_20.html) it states that the vulnerability was fixed in Apache httpd 2.0.64-dev

But no matter how hard I tried, I cannot find httpd 2.0.64-dev anywhere on the http://httpd.apache.org website.

Can someone please help. Thank you. 139.130.1.226 (talk) 00:30, 24 March 2010 (UTC)

I've not found definitive description of the Apache developers' naming conventions, but I think -dev is the name they give to "versions" in heavy development (which then turn into -alpha and -beta and finally the released version). So you wouldn't expect to see a -dev in a release mirror (because it's not a release); it's a less formal name they give to what they think 2.0.64 will be when they finally release it. This post suggests they haven't yet released 2.0.64 proper (which isn't surprising, as CVE-2010-0425 is only a few weeks old). For a definitive answer you should ask on the Apache-httpd developer's website, but I think right now if you wanted something approximating 2.0.64 you'd have to pull the tree and build it (doing so isn't hard), but then you're running unreleased and possibly untested code. -- Finlay McWalter • Talk 01:21, 24 March 2010 (UTC)

Or you can download the 2.0.63 source code, unzip, apply the patch for CVE-2010-0425 (you'll need patch for windows; how to apply a patch), then compile Apache. That is how you patch a server vulnerability. If you don't want to do that, wait for 2.0.64 to be released. Indeterminate (talk) 13:41, 25 March 2010 (UTC)

Surds on the TI-84 Plus

Is it possible to display surds on the TI-84 Plus? If not, is there a program I can get which will do it on the TI-84 plus? —Preceding unsigned comment added by 124.171.116.21 (talk) 01:51, 24 March 2010 (UTC)

TI-84 is a rather slow computer, but still a TI Basic trial-and-error program would find the most common expressions (m √a)/(n √b). Simply iterate through low values of m, n, a, and b. --Andreas Rejbrand (talk) 02:15, 24 March 2010 (UTC)

Does anyone have a link to a program to download that does that? —Preceding unsigned comment added by 124.171.116.21 (talk) 02:22, 24 March 2010 (UTC)

Ticalc.org is a good resource for this sort of program. Caltsar (talk) 15:30, 24 March 2010 (UTC)

Plugging an PC's network cable into a Cat-5 PBX wall jack fried the ethernet card

Today someone at work (it's unknown exactly who) plugged a PC network cable into a different "network jack." Apparently it wasn't a network jack, it was the Cat-5-sized connection to the PBX. (One port on every set of network outlets is apparently for that PBX and most of them are currently plugged into phones.) The tech guy told me that it fried the onboard network card. I asked him if it was a different voltage and he said yeah.

Is this a typical or common problem? Why use a PBX system that uses the same physical format as regular networked PCs, but make the electric format such that it would physically disable a network card? Is this some transition PBX system that was advanced enough to graduate from regular old phone cables to Cat-3 or Cat-5s, but not quite an IP-based system yet? NByz (talk) 02:52, 24 March 2010 (UTC)

It's the other way, RJ-45 has been a standard connector for multiline phones for ages, and UTP ethernet was originally designed around the existing availability of cheap phone cables and connectors. I got no clue about PBX's but if I had to guess, I'd imagine they use a 45 volt ring current just like a POTS phone, and that's what fried your network card. 66.127.52.47 (talk) 04:14, 24 March 2010 (UTC)

The connector itself is called 8P8C officially, although RJ-45 is widely (incorrectly) used to describe 8P8C connectors in general. The 8P8C connector in the PBX could be for a DS-1 (T1/E1) line. I've heard the story before of an Ethernet card being fried by the higher voltage of a T1. 98.226.122.10 (talk) 06:14, 24 March 2010 (UTC) Wait a minute... on reading that again, if there was a (plain, single-line) phone plugged into the jack then it wouldn't be a T1, it would be a true RJ-45 and I'll agree with 66.* above that the RING is what zapped it. 98.226.122.10 (talk) 06:17, 24 March 2010 (UTC)

An 8P8C has eight connections. This is more than enough for most uses, and gives a flexibility that makes it the overwhelming choice for office structured cabling deployments. This means computer networking (4 connections), analog telephony (2 connections), digital telephony (4-6 connections), alarm circuits (2 connections, I think), cc-cameras (3+), LonWorks (2, possibly + power) and other stuff can all be run from the same rack through the same infrastructure. The downside is that there are too many possible uses of the pins to set things up so that accidentally connecting one type of device to another won't have deleterious consequences. And the (apparent) ease of reconfiguring the cabling can fool people who think they know what they're doing into making such a bad connection. In your case it's likely that your office has a digital PBX system (which are either IP or a proprietary protocol) and a regular ethernet; the telephones connected to the PBX need power as well as signal (and at a nontrivial voltage, as they're now fairly sophisticated computer devices with screens and stuff). Good colour coding can help avoid accidental problems, but nothing can save you if someone appoints themselves tech-savant and starts repatching with abandon. -- Finlay McWalter • Talk 09:58, 24 March 2010 (UTC)

The internal PABX shouldn't use the ring line, it is not needed with modern phones and the signal on it can cause noise on lines near it. Then again you may have a BOFH with an etherkiller on your site :) Dmcq (talk) 10:30, 24 March 2010 (UTC)

That's certainly true, but it's still common for there to be analog lines present in the building - either real inbound analog lines (for ADSL, fax, and power-fail-backup) and ones synthesised by the DPABX (for fancy conference phones and again for fax). -- Finlay McWalter • Talk 10:40, 24 March 2010 (UTC)

There is a significant advantage in having phones running through RJ45 ports under each desk. If the desks are rarely moved, but the data and voice requirements at each desk change with whoever is assigned to a desk, it makes sense to have a common infrastructure to each desk (especially if you consider the disruption, time and cost of ripping up the floor every time someone needs a second phone line or extra data connections).

For example: My desk has two PCs and a phone but under the desk there are four identical RJ45 ports. The phone is plugged in to the only port labelled with a "T". However, the real distinction between which ports are phone and which are data is made in the "network cupboard" where the entire floor's network infrastructure comes together in a large patch panel and the phone connctions are patched to the PBX cabling. Astronaut (talk) 13:00, 24 March 2010 (UTC)

What is the future for SUN Microsystems

Now that ORacle has eaten the SUN. What is the future for SUN Microsystems and it's legacy? 122.107.207.98 (talk) 07:15, 24 March 2010 (UTC)

We don't speculate about the future on the reference desk. Here's the official plan from Oracle: poster for Sun customers. Nimur (talk) 09:02, 24 March 2010 (UTC)

Yeah. And we all know how good Larry Ellison's word is.^{[5], [6], [7]}--Chmod 777 (talk) 10:06, 24 March 2010 (UTC)

There have already been some very profound changes in various Solaris licensing schemes, and evidence that both MySQL and OpenSolaris will be better supported by forks. That's not speculation, sadly. 99.56.136.197 (talk) 15:20, 24 March 2010 (UTC)

fastest browser

Which net browser is the fastest lately???? —Preceding unsigned comment added by 119.235.54.67 (talk) 09:08, 24 March 2010 (UTC)

Google says Chrome (browser) is. Aaadddaaammm (talk) 09:22, 24 March 2010 (UTC)

IE is the fastest to crash. Lynx (web browser) and Links (web browser) are pretty fast. --Stephan Schulz (talk) 10:21, 24 March 2010 (UTC)

Lifehacker publishes regular browser speed tests e.g. [8] comparing Firefox 3.6, Chrome 4 and Opera 10.5, and I would personally trust lifehacker to be fairly impartial. Note that different browsers tend to be fastest at different things (startup time, javascript etc.). That said the fastest browser is indeed probably a text based browser such as Lynx (web browser), but that comes at the expense of a lot of functionality. Equisetum (talk) 11:04, 24 March 2010 (UTC)

I'll speak to the functionality of modern versions of Lynx. I often find myself connecting to the internet in very weird ways; when I need email or internet over a 100 bit-per-second connection, I can trust Lynx to not only function, but to do so with great tolerance for crummy connectivity. I can view and edit Wikipedia; I can transcode and downlink an MP3 news update from Voice of America, I can browse with full colorized hypertext to mimic the formatting of a general "web 2.0" website, I can block advertisements, and much more. On these kinds of flaky or slow connections, Firefox, Opera, and other "standards" all suffer timeouts, graphics kludges, and total system failure. So, by that standard, Lynx is by far the fastest browser in terms of scaling down the latency chain - when the network can deliver 100 bits, Lynx uses 100 bits for useful work (while Firefox blows it on a frivolous AJAX request so I can see an animated twitter logo). I currently have Lynx Version 2.8.7pre.6 on Ubuntu 9.10, and it is fantastic as a failsafe browser. Nimur (talk) 15:52, 24 March 2010 (UTC)

is there any software that can answer trivial questions about "is there any number that?"

Is there any software that can answer trivial question ssuch as "is there any integer that is both less than 0 and greater than 0" or "is there any integer that is equal to 8 and that is equal to 9?" Thank you. 84.153.234.218 (talk) 14:29, 24 March 2010 (UTC)

In plain language? Probably not. When expressed in algebraic language? Any scripting language can do this quickly. The question is whether you are trying to get the software to parse English for you or whether you are trying to get it to parse logic/math. For a computer the latter is a trivial task when put in the right terms. --Mr.98 (talk) 15:11, 24 March 2010 (UTC)

For a lot of things, it's possible to put together a quick program to find something like that out. But not always, even if the terms are well-defined. For example, the question "is there any even integer greater than 2 that isn't the sum of two primes?" has eluded mathematicians for over 250 years.

You can sometimes coerce Wolfram Alpha into solving these kinds of problems (http://www.wolframalpha.com/input/?i=x+>+0+and+x+<+50+and+prime(y)+%3D+x), but figuring out its language is hard. Paul Stansifer 15:28, 24 March 2010 (UTC) dangit, corner cases of MediaWiki syntax are hard, too

This shell script will correctly answer your example questions and others like it:

while read; do
  echo "No."
done

--Sean 15:40, 24 March 2010 (UTC)

Any of the programs listed at Interactive theorem proving should be able to do this. (Though I'm not an expert at using them.) Fair warning: these things are very difficult to use. Staecker (talk) 16:41, 24 March 2010 (UTC)

Depending on how complex you get, and how you word it, Wolfram Alpha Alpha might be able to do it. Like, "is 65537 prime", which is pretty cool. Shadowjams (talk) 05:29, 25 March 2010 (UTC)

Ticker tape transmitter keyboards?

Ticker tape, originally from 1867 stock ticker printers, was in use until the early 1970s, and seems to me an indelible part of the western psyche because of the fact that the ticker tape parade was for several decades the highest de facto honor bestowed on war, science, and exploration heroes by the populace. It is easy to find pictures of and descriptions of the ticker tape printers, but I have only been able to find this lithograph ("Sending Messages over Ticker System," Scribner's Magazine, July 1889) of the transmitter, described thusly: "As of 1883, quotations were sent using a transmitter, 'the keyboard of which has much the same appearance as the keyboard of a piano, the black keys representing letters and the white keys figures and fractions.' When an operator struck a key on the transmitter, one of two small wheels (one for letters, the other for numbers) in each connected ticker revolved until the desired letter or figure came into position to print on a paper tape that passed through the device."[9]

This is the earliest example of digital telecommunication equipment, so it would be great if we could get a better picture of one of those keyboards. There are thousands of ticker tape machine pictures easily available, but are there any surviving transmitter machines or a better picture of their keyboards? 99.56.136.197 (talk) 15:04, 24 March 2010 (UTC)

Getty images http://cache4.asset-cache.net/xc/JH5652-001.jpg?v=1&c=IWSAsset&k=2&d=2AC75F6FAA20674CD1900A18F97E500B0EF1EBF13E19BD2549207362A3F24453 may be too modern for you. -- SGBailey (talk) 17:00, 24 March 2010 (UTC)

I don't know how that photo is labeled at Getty, but it shows punched paper tape which isn't really the same thing as ticker tape. --LarryMac | Talk 18:21, 24 March 2010 (UTC)

Also this one? http://www.juliaauctions.com/auctions/archived/toy/jun01/pict0113.jpg -- SGBailey (talk) 17:02, 24 March 2010 (UTC)

That seems to be an ordinary mechanical typewriter mounted below a ticker tape printer. 99.27.201.226 (talk) 19:36, 24 March 2010 (UTC)

Caret browsing

My Mac offers me caret browsing, but nowhere in the Help or manual is caret browsing explained... please somebody put me out of my misery.Froggie34 (talk) 16:17, 24 March 2010 (UTC)

caret navigation — look for your cursor, press some arrow keys. ¦ Reisio (talk) 16:54, 24 March 2010 (UTC)

You're talking about your web browser, right? Here's how normal mode and caret browsing mode differ:

In the normal mode, the arrow keys will control the scroll bars and scroll the window immediately. If you want to select some text on the page, you have to use the mouse.

In caret browsing mode, a text cursor (a blinking vertical line) is always visible on the page, even on parts of the page where you can't edit text. The arrow keys move the text cursor, and only once it goes beyond the edge of the window does the window scroll. You can select text without using the mouse: Move the text cursor to where you want to start, then hold Shift while you press the arrows keys to highlight what you want. --Bavi H (talk) 02:50, 25 March 2010 (UTC)

There is a difference between a (mouse) cursor and a (edit control) caret. --Andreas Rejbrand (talk) 16:41, 28 March 2010 (UTC)

Cloning a linux install, then using the hdd image on a different pc

Hi Wikipedians,

I am not sure how to do it (or if it is possible at all): I wan't to be able to clone a linux install (Centos, running Asterisk) as a means of backup, Is there a way to use a cloned image with another machine? ex: Clone the HDD on System A, then if say System A's board dies out, use the cloned HDD on System B (both systems have dual NICs btw)? I am primarily concerned regarding the network interfaces / devices working properly, as I've noticed sometimes with the same machine, one install may label a different NIC for ETH0 or something. Also, will it matter if System A happens to be Multi-Core and System B single-core?

Software recommendations would be welcome.

Thanks for helping a Linux Newb :) PrinzPH (talk) 18:37, 24 March 2010 (UTC)

I've done just this (strictly moving a linux install from one machine to a quite dissimilar newer one, but that's the same effect as what you propose). I just plonked it in the new one and it worked. The only thing that didn't work (out of the box, without me doing anything) was indeed the assignment of the ethernet adapter. On the system I was using (a recent Ubuntu Linux) these were assigned by udev according to /etc/udev/rules.d/70-persistent-net.rules which contained a line that said (in essence) "reserve /dev/eth0 for a device with MAC foo". In the new machine the ethernet adapters were different, so that rule didn't find anything to match, but udev reserved /etc/eth0 anyway (it does that incase you want to have a removable adapter, like a USB one, always be at the same device name). The kernel found the installed ethernet adapter in the new machine and assigned it to /etc/eth1. As the /sbin/ifup script (and its buddies) were coded for eth0, they didn't bring up eth1, so the machine had no internet. The fix is simply to comment out the rule lines in /etc/udev/rules.d/70-persistent-net.rules, which leaves the kernel to assign whatever ethernet adapters it finds to whichever /dev/eth? devices it thinks best (in essence by PCI discovery order). The only other thing I can think of is if you have a device driver that isn't managed by your dist but by yourself - I know next to nothing about Asterisk installs, so I don't know how it gets drivers for things like linecards. I also know nothing whatever about Centos, so I don't know if it has udev or devfs (which does the same job, but differently). -- Finlay McWalter • Talk 19:05, 24 March 2010 (UTC)

As long as the systems are the same arch, the worst case scenario is that you'd have to make a tweak or two as Finlay's described, and maybe add some new drivers to your kernel, etc..* ¦ Reisio (talk) 00:06, 25 March 2010 (UTC)

With binary distributions such as CentOS, it's often possible to plug the drive into another computer, even with a closely related but not identical architecture. A 32-bit installation originating from a 32-bit x86 computer can be plugged into an x86-64 computer, for example. In that case, the processor will run in backwards-compatibility mode, which means you cannot address more than 4GB RAM, but it will work nonetheless. (However, plugging an x86-64 installation into an x86-32 computer will not work.) There is one very important caveat when moving installations between processors, though: any programs compiled with GCC's -march= flags may need to be recompiled even between identical architectures but different processor models. -march applies aggressive optimisations for specific CPUs, even at the cost of compatibility with other CPUs, meaning the machine code may not be compatible even between two closely related CPUs by the same vendor but with a different model number. On CentOS, the only programs potentially affected by that are the ones you have compiled from source. --Link ^(t•c•m) 08:19, 25 March 2010 (UTC)

Firefox - Add-ons no longer shown in menus

I have Firefox 3.6.2. The Add-ons no longer appear in the menus anywhere. When I click on any "options" button in the Add-on page, that page freezes. As far as I recall it was working OK after recently downloading the 3.6.2 version. This might perhaps be connected with running the program called CleanUp! shortly before, although when I ran it on previous occassions with the same settings it didnt cause any problems. Anyone know what the solution might be? Thanks. I have tried re-starting the computer. 78.149.167.173 (talk) 21:21, 24 March 2010 (UTC)

I'm running the same version, I have no problem navigating through any menus. I can't find any "options" button in the Add-ons window, did you mean the "options" in the "Tools" menu? What OS are you running? 24.189.90.68 (talk) 22:28, 24 March 2010 (UTC)

All the Add-ons have disapeared completely, they are no longer in any menu nor at the top of the browser. However they are listed in the Tools/Add-ons page, but when I click on any Options button on that page freezes and I have to press Ctrl-Alt-Del to close the page. I have WinXp, Sp3. 84.13.22.69 (talk) 13:03, 25 March 2010 (UTC)

Hmm, maybe Firefox didn't update your add-ons properly, and now they're crashing FF? You might try Manually uninstall extensions and/or Manually uninstall plugins, and then reinstall them if that fixes the Add-ons tab. Indeterminate (talk) 13:22, 25 March 2010 (UTC)

Would it be easier to simply uninstall Firefox, re-install it, then reinstall all the plug ins? Perhaps I ran the CleanUp! too early after upgrading to 3.6.2 and it deleted something important. I may not have restarted the computer between using them. 84.13.22.69 (talk) 15:01, 25 March 2010 (UTC)

I did uninstall everything and then reinstall everything, and now it is working OK. I havnt tried running CleanUp! again yet. 84.13.34.56 (talk) 13:21, 26 March 2010 (UTC)

March 25

fortran 90

HOW CAN I WRITE e^-m in fortran 90.Supriyochowdhury (talk) 01:26, 25 March 2010 (UTC)

Try this:

(e**(-m)) * (e-m)

StuRat (talk) 01:49, 25 March 2010 (UTC)

Assuming that by "e" you mean e (mathematical constant), Fortran provides a function to calculate e^x: EXP(x) (in which "x" needs to be a REAL or COMPLEX value and the function returns the same sized result). Also remember that EXP(1.0) will return the actual value of the mathematical constant.

The exponention operator ** can be used for integer exponents, but if you want to work with REAL or COMPLEX values you will need to use the log & exponent method. So on the other hand, if you want to raise some other value by any power, remember that a^b ≡ e^(ln(a)*b). Fortran provides a function to find the natural logarithm: LOG(x) (in which "x" needs to be a REAL or COMPLEX value and the function returns the same sized result). So, in Fortran you can raise a to the power of b by writing EXP(LOG(a)*b). Astronaut (talk) 02:41, 25 March 2010 (UTC)

How do I restore minimized windows ?

Resolved

I'm in Windows 98 (StuRat ducks to avoid insults) and my Menu Bar/Task Bar has gone bye-bye. The obvious thing to do is to reboot, but first I'd like to pop up my minimized windows and save my work. So, how can I do this with keystrokes ? Isn't there a "maximize all" command ? StuRat (talk) 04:17, 25 March 2010 (UTC)

Does alt-tabbing to them each work? Comet Tuttle (talk) 04:38, 25 March 2010 (UTC)

If you can pull up Task Manager (using ctrl+alt+del), you can restart explorer.exe from the "Run" menu. Nimur (talk) 06:14, 25 March 2010 (UTC)

Windows-M is minimize all, and SHIFT-Windows-M maximizes all (I think). Not sure if that worked with win98. Sandman30s (talk) 07:41, 25 March 2010 (UTC)

Thanks all. Alt-Tab worked, Shift-Windows-M didn't, and the Task Manager under Windows 98 only kills processes or reboots the computer, there's no Run menu there. StuRat (talk) 13:09, 25 March 2010 (UTC)

(EC) A bit late, but anyway: Just to clarify, you are referring to the task bar? Alt+Tab normally works, but maybe not if explorer.exe is not running. I have never heard of Shift+Win+M, and it does not work in Win 7. Ctrl+Alt+Delete will not allow you to start any programs in Win 9x. (Nimur: have you forgotten the dialog?) I do not remember Win 9x sufficiently well, but I wonder if not Ctrl+Shift+Esc will open the alternative program manager window when the Start Menu is unavailable, in which you do can start explorer.exe. --Andreas Rejbrand (talk) 13:11, 25 March 2010 (UTC)

(even later) StuRat could have tried restarting Explorer.exe (the program that provides the desktop and menu bar). Win+R should make the "Run..." dialog appear even in Windows 98 and you can restart Explorer from there. Astronaut (talk) 13:36, 25 March 2010 (UTC)

Yes. But I am not 100 % sure that Win+R will work if not explorer.exe is running... That's why I mentioned the "alternative program manager" window. --Andreas Rejbrand (talk) 13:45, 25 March 2010 (UTC)

I did mean the Task Bar, and I've now added that to the original Q. Control + Shift + Escape brings up the Start menu, from which I can pick the Run menu, and Win + R takes me directly there. As for restarting Explorer.exe, that's the type of thing that would take down a computer that's already having problems (hence the missing Task Bar), so something I'd want to try only as a last resort. StuRat (talk) 16:15, 25 March 2010 (UTC)

PDF assistance required

Resolved

Dear Refdeskers, short and sweet. I require assistance regarding opening two PDF files, which I had obtained from a guy I do projects for. They are here and here. He swore he can open them, I've tried Adobe Reader, Foxit, Evince, PDFedit, GIMP, Inkscape and Google Docs and got nothing. Maybe one of you guys manages to open these two files? These are nothing to worry about, nor are they NSFW (unless industrial laundry machines turn you on). On the other hand I won't be surprised if they really are corrupt. Thanks in advance and cheers! --Ouro (blah blah) 13:38, 25 March 2010 (UTC)

They look corrupt to me. Indeterminate (talk) 13:49, 25 March 2010 (UTC)

They are corrupt. I wonder if this is what happened: He emailed them to you. You saved the PDFs from the email. You couldn't open them, so you posted them online. If so... The ones on his end were not corrupt. The corruption came in your attempt to save the files from your email. PDFs have a high tendency to corrupt in email because they take soooo loooong to download when you save them. Most people don't wait and only download a fraction of the PDF to their harddrive. Often, I have to access my mail through the web to force it to do a web-download of the PDF instead of email download. -- kainaw™ 13:56, 25 March 2010 (UTC)

Yeah, from glancing at them in hexedit, it looks like they aren't complete. At least, they don't end the same way other PDFs do. Indeterminate (talk) 14:04, 25 March 2010 (UTC)

Downloaded them from online using three different machines (different OSes and different configurations), and every time they came out corrupted. Downloaded them with a package of other PDFs that didn't get corrupted during download. Thanks for reinforcing my judgement, friends. Cheers!! --Ouro (blah blah) 14:11, 25 March 2010 (UTC)

The nuts and bolts of quantum computing

"It can simply compute a whole bunch of answers at once in such a way that the "correct" answer drops out at the end."

Could someone explain this please? I take it that a quantum computer is parallel in some way. Can anyone explain how? 84.13.22.69 (talk) 14:56, 25 March 2010 (UTC)

I don't know if this is relevant, but meteorologists run many different models on different computers, simultaneously, to predict the weather. They then will give a range of results, such as possible hurricane tracks, based on the summation of all those results. StuRat (talk) 16:18, 25 March 2010 (UTC)

Have you looked at the quantum computer article? A really oversimplified description: a regular computer has bits that are flipped on or off independently. A quantum computer uses "quantum bits" (qubits) that are not entirely on or off, but that are in a mixed state that describes a generalized probability distribution, set up so that the qubits are not independent but entangled. The system is in a set of superposed states (like the fictional Schroedinger's cat is simultaneously alive and dead) that don't resolve until you observe them with a measurement (one of the big practical obstacles is avoiding doing observations until you're done with the computation, see decoherence). There are then operations you can do on the qubits that alter the probability distribution, so that the most likely observation is the one that expresses the answer to your problem. You then observe the state to get the answer. 66.127.52.47 (talk) 23:11, 25 March 2010 (UTC)

I had read the article thank you. Having another look at it and its links, then relevant part is Shor's algorithm, and there is an explaination "for the man in the street" in the links at the end which I havnt had time to read yet. I'm still wondering why qbits can do things that are more parallel than what an electron can do, hopefully the pop article will answer that. 84.13.34.56 (talk) 13:38, 26 March 2010 (UTC)

Here is a great article from Scientific American: The Limits of Quantum Computers. The problem of quantum computing is that we do not know a way to map boolean algebra (which is really the basis of every current programming language and algorithm programming paradigm) into input/output states for quantum mechanical entanglement. In other words - we know that there are ways for quantum states to interfere; we know that we can do certain things to electrons to force their spins to go up or down; we know how to measure the resulting spin based on what we did to the electron. But we do not have a way to represent algorithms in a way that we could apply physical inputs to a set of electrons such that when we measure their spins, the spins encode the answer to our algorithmic query. We do know a way to apply stimuli that encode algorithms as inputs to digital electronics circuits: we use MOSFETs to build inverters and wire them sequentially to represent boolean logic finite state machines; and we read the resulting voltages and decode those voltages back to a logical algorithm result. No equivalent mapping back and forth between logical algorithm description and physical-stimulus/effect-relationships is known for quantum computers.

Shor's algorithm describes the mapping between logical problem description and physical process. Unfortunately, it only represents the mapping for one particular algorithm. Until we have a generalizable way to map any abstract logical description into a set of inputs for a quantum computer, we don't really have a practical way to use them. Nimur (talk) 17:50, 26 March 2010 (UTC)

84, the parallelism comes from the entanglement between the qubit states. You know how they say that Schroedinger's cat is simultaneously alive and dead? Well, a 100-qubit quantum register is (figuratively) in 2¹⁰⁰ states simultaneously, so computations that you do on the register happen on all of those states in parallel. You might also like Aaronson's paper on NP-completeness and physical reality.[10] 66.127.52.47 (talk) 07:15, 27 March 2010 (UTC)

Thanks, I will read those. If quantum computers will be able to do brute searches easily, then that suggests that truely intelligent AI will come about by raw brute search rather than merely imitating human ways of thinking. If my experience of playing against brute search WZebra reversi is correct, then they will behave in what seems like a chaotic way and be cold and sinister things with an icy heart - cue the SF story. 84.13.201.209 (talk) 10:13, 27 March 2010 (UTC)

Linux filesystem problem?

On Fedora 12 Linux, I accidentally rewrote the partition table of a new hard drive while I had one of its partitions mounted. I got a nasty-looking error message from fdisk, but then I umounted the partition, and rewrote the partition table again. There was no loss of data because the drive was new and had no data to begin with. But will this cause problems in the future? JIP | Talk 18:15, 25 March 2010 (UTC)

If it truly has no data and you are worried about future problems, you can umount it, and reformat it. However, if it mounts properly and shows the correct system type and size, I do not see a problem. You can, if you want to, chkdisk to see if it has anything bad on it. But, for the time that will take, I'd just format it. Of course, I completely format all my drives every year. So, I'm not a good example. -- kainaw™ 18:42, 25 March 2010 (UTC)

By "rewrote the partition table", do you mean that you re-ran mkfs? I've never heard any reason to believe that mkfs pays attention to the original contents of the partition, so in that case it shouldn't matter what was on it before. Paul Stansifer 12:26, 26 March 2010 (UTC)

No, I meant I re-ran fdisk. What I did, from the beginning, was that I mounted a partition on the disk, then ran fdisk to modify the partition table, having forgotten I still had a partition mounted. I deleted the partition, created a new one in its place, and saved the changes. At this point fdisk said that changes could not be saved, and the kernel would still use the old table until the next reboot. I then realised I had a partition still mounted, so I umounted it, and ran fdisk again, doing the exact same changes. This time it didn't give an error message. I then ran mkfs on the new partition I had created in fdisk. JIP | Talk 10:02, 27 March 2010 (UTC)

Access 2003 Question

OK, I know I'm clueless and I'm not very experienced with Access, but can someone please help me with this without trying to explain programming code? I have a database with a list of medical simulation scenarios. Each scenario has mutiple columns with nothing but an 'x' in it. So, scenario 1 has an x in the "Respiratory", "Pulmonary" and "Ecmo" columns, scenario 2 has an x in the "Respiratory", "X-Ray" and "Chart" column, etc. I am trying to set up a form where someone can go in and choose which criteria they want, then hit a button and all the different scenarios that match their criteria will pop up. I can figure out how to hit one button and have it return all the scenarios with an x in the respiratory column, but how can I set it up where I can pick mutiple criteria and it will only return the records that meet all the criteria I choose? Thanks in advance! Tex (talk) 19:17, 25 March 2010 (UTC)

What you need is a little bit of VBA that creates a custom SQL query for the code you want. Let's say that you had "Respiratory" indicated by a checkbox named checkboxRespiratory, "Pulmonary" by checkboxPulmonary, and so on. Then you could assign it to your list of results as the source. The VBA would look something like this (not tested, and I'm a little rusty on VB):

Dim sqlquery as String

Dim sqlAnd = false

sqlquery = "SELECT * FROM tableScenarios WHERE ("

If checkboxRespiratory.Value = True then

If sqlAnd then sqlquery = sqlquery & " AND"

sqlquery = sqlquery & " Respiratory='x' "

sqlAnd = true

End If

If checkboxPulmonary.Value = True then

If sqlAnd then sqlquery = sqlquery & " AND"

sqlquery = sqlquery & " Pulmonary ='x' "

sqlAnd = true

End If

If checkboxEcmo.Value = True then

If sqlAnd then sqlquery = sqlquery & " AND"

sqlquery = sqlquery & " Ecmo ='x' "

sqlAnd = true

End If

sqlquery = sqlquery & ")"

ResultsList.RowSource = sqlquery

Or something like that. (I can't give more specific examples without knowing a bit more about how your form is set up.) Does this make sense? In the end your code will give you an SQL statement that looks something like "SELECT * FROM tableScenarios WHERE (Respiratory='x' AND Ecmo ='x')". Then you put that as the RowSource of a Listbox (or Combobox, or there are other ways to do it).

(Note that the whole reason there is the sqlAnd bit is because you need to have ANDs between each evaluation in the SQL query, but don't want a trailing AND. Doing it the way I did it is a quick and dirty way to do this.)

Does that make sense? That's one way to do it; there are others. I have not tested the above code, it assumes your database data is really made of strings (is really "x" and not a True/False field), which might not be the case. It is not hard to modify, though, but understandably using VBA to create SQL probably will make you a bit nervous at first if you are familiar with neither. --Mr.98 (talk) 23:56, 25 March 2010 (UTC)

Thanks Mr.98. Yeah, all that stuff is Greek to me. I was hoping to be able to do it just by using the GUI. I'll definitely give this a try, though. Thanks a lot! Tex (talk) 14:13, 26 March 2010 (UTC)

I'm not sure there's an easy GUI way to do it. I don't mind writing the code (as you can see it is not too complicated if you know VBA) but I'd need to know a little more about the forms and tables you are using. (What the control types and names are on the forms, what the exact table design is, in particular the field types). --Mr.98 (talk) 15:54, 26 March 2010 (UTC)

Well, I wouldn't want you to go to any trouble. I know just enough Access to get me in trouble, so when someone said they had an Excel spreadsheet, I thought it would be easy enough to put it into Access so that queries could be run on it. So, I just imported a spreadsheet into an Access table. There's nothing special about the data types, it's all text. The exact structure is:

Name	Learner	Level of Acuity	Respiratory	X-Ray	BPD	Chart	Pulmonary	RDS	ECMO
Scenario 1	Advanced	Red	x	x		x			x
Scenario 2	Intermediate	Yellow	x		x		x		x

And it goes on for over 50 different scenarios. The form I set up is just a basic form where I envisioned having several drop down boxes. The person would choose "Respiratory" from the first drop down menu, "Pulmonary" from the second drop down menu and "Ecmo" from the third drop down menu and then hit a button that would say "Find all scenarios that meet your criteria". It would then run some kind of query in the background and return only those records that have respiratory, pulonary and ecmo with an x in the cell. If they left the third drop down box empty, it would return all the records that have an x under respiratory and pulmonary. Make sense? Seriously, I would really appreciate your help, but I don't want to waste your time. Tex (talk) 16:30, 26 March 2010 (UTC)

It's no problem. I assume that the table is named "tableScenarios"—if it is not, feel free to rename it every time I use it below. I am using Access 2002 so the particulars might be a tiny bit tweaked, but probably not:

1. Make sure that the "Name" is designated as the Primary Key. To do this: from the Database window, choose Tables, choose tableScenarios, choose Design. Make sure there is a little key next to "Name". If there is not, select "Name" and choose Edit > Primary Key. Close the Design window.
2. From the Database window, click on Forms, then click on New. Click OK (Design view, don't give it a table to base it on).
3. Add a ComboBox control to the form. When the Wizard menu comes up, choose "I will type the values that I want." Click "next". You want it to be 1 column. Just type in X-ray, then hit tab, type in BPD, hit tab, type in Chart, hit tab, and so on for the fields. Click Next, a caption like "Field filter 1", click Finish. You should now have a little drop-down box on your form page.
4. Right click on the drop-down box you made, and choose Properties. Click on the "Other" tab, and change its "Name" field to "cbo_filter1". Then click on the "Data" tab, and set "Limit to List" to "Yes".
5. Select the drop-down box and its caption, copy and paste it two times. Move the other two instances into reasonable positions. In the same fashion as before, change their "Name"s to "cbo_filter2" and "cbo_filter3" respectively. (It doesn't actually matter if they are in order.)
6. Now add a List Box control to the form. When the Wizard comes up, hit Cancel (we don't want to use the Wizard). Select the List Box you just added, go to its Properties, change its "Name" to "list_results". In the Properties window, click the "Format" tab, change the "Column Count" field to 11. Change the "Column Heads" field to "yes". You can position the List Box in a convenient place at this point.
7. Now add a button to the form. When you get the Wizard, hit Cancel (we don't want to use the Wizard). In its Properties, go to "Other", change its "Name" to "btn_Search". Under "Format", change its "Caption" to something useful (like "Search"). Now click on the "Event" tab, and under "On Click", select the drop-down menu and select "Event Procedure." Then click the ellipses ("...") next to "Event Procedure", and it'll launch the code editing window.
8. After "Private Sub btn_Search_Click" and before "End Sub", paste in the following code:

Dim sqlquery As String 'set up our SQL string variable
Dim haveField As Boolean 'set up a variable that will tell us whether any fields have been selected
haveField = False 'set that variable to "false" to begin with

sqlquery = "SELECT * FROM tableScenarios WHERE (" 'start making our SQL query (select all records from the table where the following conditions apply...)

If cbo_filter1.Value <> "" Then 'if the first combo box has anything selected in it...
    sqlquery = sqlquery & "Nz([" & cbo_filter1.Value & "],'')" & "<>''" 'add to the SQL string the name of the field to check for, and make sure it is not null (if it is, Nz will set it to an empty string), and then compare it to an empty string.
    haveField = True 'set the 'have already entered a field' variable to true
End If 'end the 'if' conditional statement

'The only tricky bit about the above is all the "Nz([" etc. business. Nz() is a function that basically says, "if the field is NULL, report it as this instead." So if I say Nz(variable, ''), I just mean, "if variable is null, report it as an empty string."
'This is useful here because sometimes tables will store empty cells as null and sometimes as empty strings. This is an easy way to hedge our bets on what it will be (and it doesn't matter which one it is, we want it to count as empty.)
'Lastly, just note that cbo_filter1.value will be the text of the combo box. We put it in brackets [] because field names like "X-ray" would not be acceptable otherwise.

If cbo_filter2.Value <> "" Then 'same thing, but with the second combo box
    If haveField = True Then sqlquery = sqlquery & " AND " 'if we already have a field variable entered, add AND to the SQL query
    sqlquery = sqlquery & "Nz([" & cbo_filter2.Value & "],'')" & "<>''" 'same check as before, but with the second combo box
    haveField = True 'same as before
End If

If cbo_filter3.Value <> "" Then 'same thing, but with the third combo box
    If haveField = True Then sqlquery = sqlquery & " AND " 'if we already have a field variable entered, add AND to the SQL query
    sqlquery = sqlquery & "Nz([" & cbo_filter3.Value & "],'')" & "<>''" 'same check as before, but with the third combo box
    haveField = True 'same as before
End If

If haveField = False Then sqlquery = sqlquery & "1=1" 'if they select NO fields, let's assume they want ALL records, and so we set the "WHERE" to a statement that will always evaluate to be 'true' for all records (that 1 equals 1)

sqlquery = sqlquery & ")" 'end the SQL query

list_results.RowSource = sqlquery 'set the list box to use the SQL query
list_results.Requery 'refresh the listbox

"OK", you're thinking, now I'm using dodgy meaningless code I got off the internet. The comments though should allow you to follow the flow of the script and what it is doing. We are just creating an SQL query based on information on the form, and then passing it to the list box. (I have tested this code, so this time I am sure it should work.)

1. Close the code editor, close the form, (it will prompt you to give it a name -- "Searchform" is fine, save changes!). Now if you click on "Searchform" under the "Forms" tab of the Database window, it should prompt you for your three fields.

Let me know if the above works. I have a saved file of it I could e-mail you if you give me an e-mail address to use, if you are having trouble getting everything to work. (In my experience though going through steps like that is a good learning tool!) --98.217.71.237 (talk) 00:33, 27 March 2010 (UTC)

IE8 - default to display the "Find" tool

Is there a way I can set IE8 (v8.0.6001.18702 on fully patched WinXP MCE SP3) to start with the "Edit->Find on this page" tool open on a toolbar? I can't find any native way (through the various menu/toolbar options) to do so and my various searches of support sites yield nothing. Basically, I do enough searching for text in Wikipedia pages that I'd rather have the Find box on a toolbar all the time. Franamax (talk) 19:57, 25 March 2010 (UTC)

Ctrl+F is not fast enough? --Andreas Rejbrand (talk) 20:49, 25 March 2010 (UTC)

...or just install Firefox instead and be able to find text simply by typing it, without the need to display any dialog or select any menu option. JIP | Talk 20:59, 25 March 2010 (UTC)

Well no, ctrl-F isn't fast enough or I wouldn't have asked. It requires an extra switch between visual, key-sequence, and textual tasks. I wish to go directly from browsing to search by clicking in the pre-existing find box sitting right there in the otherwise empty space on my toolbar. Is that possible? (And I appreciate the advice on browser platforms but for various reasons I need to stick with the "mainstream"). Franamax (talk) 01:36, 26 March 2010 (UTC)

Backups

I now possess not zero, not one, not three, but two 1 terabyte USB hard drives intended solely to back up my internal hard drives. I intend on running a routine backup process once every few days, alternating between the drives, keeping the drive only turned on for the duration of the backup process. If one drive fails, the other still has most of the data, and I can replace the faulty drive with a new one. But is there anything I can do to make sure the other drive doesn't fail as well before I can replace the one that (hypothetically) did fail? I am fairly sure that now that I have two drives, simply having more than two would be superfluous, the main point is that there no longer is a single vulnerability to the entire backup. JIP | Talk 21:09, 25 March 2010 (UTC)

If you can solve that problem, you can prevent any drive from failing in the first place. The risk of two drives failing at once is why there are mirroring solutions that use additional redundancy so it takes two or more drive failures to lose data. If your data is on your computer and two backup drives, you've got double redundancy, so the only way you lose your data is if the remaining two go down before you can replace the first to fail. Statistically speaking, you're in pretty good shape, as long as you acquire replacements quickly. —ShadowRanger ^(talk|stalk) 21:15, 25 March 2010 (UTC)

I was going to suggest that you make sure the two disks are different models, ideally by different manufacturers - if instead you bought two disks of the same model at the same time, it's likely they're from the same batch. If you are unlucky enough to get a bad batch, then that increases the chance that the failure of the first will be followed by the failure of its counterpart (that is, that the failures have a common causation and are not unrelated events with independent probabilities). But if you've already bought the disks, then it's too late for that. The scheme you describe still has, on the face of it, a single-point of failure - if the disks are stored in the same building as the original machine and something affects those premises, it affects the backups too. So a burglary, a legal dispute, a fire, a flood, a release of toxic gas from that oil refinery down the road which prevents you from going home for a couple of weeks, all these make your backups useless. Remote backups (where you operate two or more machines, and they backup each other with rsync over ssh overnight) or hosted online backups (where your backup lives at Amazon or wherever) are much safer from this perspective. Even if you're not willing or able to go to these lengths, think about where the backup disks are when they're being stored. Are they in a pile on top of the machine, or are they kept in a locked firesafe in another room? -- Finlay McWalter • Talk 21:30, 25 March 2010 (UTC)

Very good point. I tend to overlook that sort of thing. I figure if my apartment bursts into flames, I've got bigger things to worry about, but on further consideration, there is a lot of stuff I simply could not reproduce if my computer went down. I keep the important stuff on RAID-1 disks, but I really ought to spring for off-site backup. —ShadowRanger ^(talk|stalk) 21:42, 25 March 2010 (UTC)

It's true that if you have a true disaster then backups might be the least of your worries. But, for individuals and particularly for business, there are all kinds of unexpected nasties that can temporarily deny you access to your premises or your machine, that only become a disaster if your backup strategy is bad. I worked one place where the river flooded the entrance to the office estate, meaning no-one could get to the (perfectly dry and functional) office. This happened on the day of a (panic mode) deliverable, leading to much wailing and gnashing of teeth - but I just sent everyone to another office where the overnight backup was available and everything got done fine. For an individual things don't need to be at all advanced; I just tar my "fragile" folder to a DVD, keep one copy at home, another in a firesafe at home, and another in a relative's safe in their home (they're not all done concurrently), so the worst case (total fire) would cost me about a month's stuff (and as it's mostly copies of viagraspam, that's an appropriate level of risk). -- Finlay McWalter • Talk 22:35, 25 March 2010 (UTC)

Get some more drives. The site [11] has a cute parable (warning, it ends with a gentle sales pitch) that is pretty informative about various issues of backup strategy. 66.127.52.47 (talk) 23:15, 25 March 2010 (UTC)

If you're serious about not losing your valuable data, I would also suggest a fire safe. As others have said, if you're unlucky enough to have a fire, or a theft, it's quite likely you will lose all 3 drives. With a fire safe remote from your PC, you have much better insurance against that. --Phil Holmes (talk) 09:24, 26 March 2010 (UTC)

You should keep a backup far away from your house, preferably 100's of miles away, but in your office or car or something like that is better than nothing. Don't forget to encrypt it if it contains anything private. A bank safe deposit box is a good place to store long-term backups. 66.127.52.47 (talk) 07:19, 27 March 2010 (UTC)

I'm hesitant to keep a remote backup at a family member's or friend's home, or at my office, because I just don't like the thought of someone else potentially having access to my data. I'm otherwise convinced that a remote backup is a good idea. A bank safe deposit box would therefore be a suitable solution, but I don't know how much having such a thing would cost. JIP | Talk 10:05, 27 March 2010 (UTC)

March 26

Converting from flv to image files

I want to convert a .flv video file into a series of video images, one per frame. I used to be able to do it with winamp, but now that i have windows vista, i dont think the operating system allows the program permissions to start making the image files.

How can i convert every frame of an flv video to an image file? This is all i want to do, and it should be an easy solution.

Thanks! 137.81.112.175 (talk) 00:00, 26 March 2010 (UTC)

Both WinFF and HandBrake should be able to manage that.
If you have a Unix box handy, it's as simple as ffmpeg -i foo.flv %d.jpg. ¦ Reisio (talk) 00:56, 26 March 2010 (UTC)

GOM Player (sic) can convertat at least individual frames to images, do not remember if it can do a range of them. 84.13.34.56 (talk) 13:45, 26 March 2010 (UTC)

You don't need a unix-box; you can install FFMPEG on Windows. You can use the same command described above, once FFMPEG is installed. The FFMPEG article explains details and links to the main site. This is a command-line tool; WinFF provides a graphical front-end for Windows. Nimur (talk) 08:52, 27 March 2010 (UTC)

Google Earth down?

Anyone know what's up with Google Earth? For about the past 8 hours it's been telling me it can't connect to the database. I wonder if their servers are down? —Steve Summit (talk) 00:31, 26 March 2010 (UTC)

Seems to work alright here. 5.1.3533.1731 Linux ¦ Reisio (talk) 00:59, 26 March 2010 (UTC)

I guess it's just me, then. Strange. (Rebooting didn't help, either.) —Steve Summit (talk) 13:23, 26 March 2010 (UTC)

This is incredibly unlikely, but maybe you're being affected by this alleged problem by which some traffic entirely outside the Great Firewall of China is being affected by it. Comet Tuttle (talk) 18:16, 26 March 2010 (UTC)

Google Earth is fairly profligate with IP connections; perhaps you have special security or firewall settings that are stopping its from getting what it needs. For the trace I monitored, it talks to a bank of 4 addresses in the 66.102.9.x (to at least .91 .93 .136 and .190) all of which are owned by Google in MTV and resolve to their 1e100.net domain, and and to addresses in 216.239.59.x (with the same four options for final octet), which appears to be their data centre in Wisconsin. In practice it issues standard HTTP GET requests (on port 80) for stuff like http://kh.google.com/dbRoot.v5?hl=en-GB&gl=gb - if you can't get that (with a web browser or wget) then that would suggest you have some networking issue (if it's not firewall, maybe a stale or corrupt DNS cache). -- Finlay McWalter • Talk 21:12, 26 March 2010 (UTC)

Shift+F10 not working in Opera

I don't know if anyone else is experiencing this, but shift+F10 isn't working in Opera 10.51. 24.189.90.68 (talk) 01:18, 26 March 2010 (UTC)

When I need to do spell check, I mean. 24.189.90.68 (talk) 04:23, 26 March 2010 (UTC)

partitioning a new laptop with preinstalled os

My friend bought a Dell Inspiron Laptop with Windows 7 preinstalled. It has only one partition and he would like to have a few more added. Can I do that with Gparted without damaging the existing partition? The Windows 7 CDROM that was bundled with the laptop doesn't have a serial on it, my friend says. How do they provide the s.n. usually?--117.204.86.16 (talk) 02:17, 26 March 2010 (UTC)

Look on the bottom of the laptop. There should be an official Windows sticker with the serial number attached. Astronaut (talk) 04:41, 26 March 2010 (UTC)

Yes, if you're careful with gparted then this shouldn't be a problem. In addition to the sticker that Astronaut mentions (which I'd recommend you photograph or photocopy, as these can get scuffed up after a few years of laptop use) many laptops also record their OEM licence code in flash memory on the motherboard - so if you reinstall the correct OEM windows (usually from system restore) it automatically gets the licence key from flash and you don't have to enter it manually. (This doesn't work at all if you try to install another version of windows, particularly a retail build, for which that OEM licence isn't valid). -- Finlay McWalter • Talk 11:15, 26 March 2010 (UTC)

That technology is called SLIC if you want to look it up. F (talk) 06:08, 27 March 2010 (UTC)

vba to android?

I have created a VBA + Excel app, trying to make into an android app for marketplace. Anyone know how android works? Could I just copy-paste vba script? minor alterations? major? Will it run faster/slower?Thanx 173.30.18.29 (talk) 06:27, 26 March 2010 (UTC)

It will be full rewrite I believe. VBA relies on a host application (Excel in your case) and Microsoft haven't released the Office Suite for Android yet. Ignoring that most android apps are written in a Java like language which bears little resemblance to VBA syntax.87.54.40.66 (talk) 11:58, 26 March 2010 (UTC)

Yeah. Basically Android applications are written in Java. Totally different language that looks nothing like VBA or Excel. It would be non-trivial to port it over if you are not fluent in Java. --Mr.98 (talk) 12:13, 26 March 2010 (UTC)

Insecurity through OS piracy?

Are there any documented cases of crackers intentionally adding security vulnerabilities to their releases of a pirated operating system? NeonMerlin 06:31, 26 March 2010 (UTC)

Haven't heard of anyone doing so, although it's quite common that some illegally downloaded software are laced with malware code, which, according to some groups, was added by certain ill-intended people and not by the crackers themselves. Blake Gripling (talk) 07:26, 26 March 2010 (UTC)

It has happened, but it's nowhere near as prevelant as your average Windows user is afraid it is. ¦ Reisio (talk) 07:37, 26 March 2010 (UTC)

In this link, Microsoft points to a German study in which they downloaded 500 pirated copies of Windows 7 and/or activation cracks, and they reported that 32% contained malware. It's in Microsoft's interest to make and inflate such claims, but it's also not in their interest to lie outrageously, in the event they are caught in the lie. Anyway, it's not Microsoft making the claim. I find the claim believable. Comet Tuttle (talk) 16:38, 26 March 2010 (UTC)

I'm not saying if you download 500 pirated copies of Windows 7 and/or activation cracks that you won't get malware in 32% of the packages, but I can't find any information on this survey, so it comes down entirely to Media Surveillance's word and unprovided definition of "malware". ¦ Reisio (talk) 17:05, 26 March 2010 (UTC)

Related: This link claims that in a study by someone called "IDC" in 2006, they purchased counterfeit Microsoft software at resellers in 17 countries and found that "more than 50 percent contained phony code, had malware, or could not even be installed." "Phony code" could mean a lot of things; I assume they mean to say that the disc was claimed to be a Windows 98 disc but was actually a copy of Windows 95, or the "Windows 98 for Dummies Companion CD", or that sort of thing. Comet Tuttle (talk) 17:32, 26 March 2010 (UTC)

Same referenceless site everyone links to for the Media Surveillance stuff. ¦ Reisio (talk) 05:24, 27 March 2010 (UTC)

Looking for a web annotation program that does certain things

Hello,

I am looking for a web annotation service that combines the following features:

1) ability to highlight text,

2) ability to insert an html anchor so that I can jump people down to a particular paragraph,

3) ability to upload my modified version of the webpage for public viewing.

The purpose is so that when I put urls into footnotes in Wikipedia, I can have them point directly to the section of the document that I'm referring to, and have that section highlighted.

However, I am unable to find a service that provides me with the second feature (ability to insert an html anchor). Does anyone know of one that does this? Thanks,

user:Agradman, editing from an IP address - 207.237.228.236 (talk) 07:35, 26 March 2010 (UTC)

I just want to add that you probably shouldn't use this for URLs on Wikipedia, just as you shouldn't use link shorteners or things like that. Why? Because someday the service you are using will probably go down (just how things work on the internet) or changes names or whatever. If the original, base URL isn't completely obvious, that means we've lost a good link. It also means that in the future finding archive.org equivalents to said good links is harder. An all-around easier way to cite specific pieces of text is to just quote the beginning of what you are quoting in the footnote reference. Keep it simple, as they say! --Mr.98 (talk) 12:09, 26 March 2010 (UTC)

Depending on third party services can be treacherous, but it's conceivable you could do it with nothing but some JavaScript. You could keep all the highlighting/annotation info in the link itself, no service necessary. ¦ Reisio (talk) 05:26, 27 March 2010 (UTC)

Do not use those links in WP, per WP:EL. 66.127.52.47 (talk) 22:46, 26 March 2010 (UTC)

OK, I am glad you intervened, because I was getting ready to start using hyperlinks from web annotation companies in my WP edits. But now, I am thinking that if these are banned per WP:EL (because of the their legitimate weaknesses in stability and reliability and possibly trustworthiness), then we should be actively looking for ways to solve this problem; until we do, we are missing out on a lot of value in being able to anchor and highlight in the documents we cite to.

• e.g. we can host the annotated copies on wikisource?
• e.g., Reisio (talk), are you saying that we could use Javascript? Is that also forbidden by WP:EL (and if so why)? Is it easy enough that you could write up an example of how this would work?

- Agradman 06:56, 27 March 2010 (UTC) (editing from an IP address, 160.39.221.14 (talk)).

I don't see that those highlighting effects have more than minor benefit. For a WP citation to a web page, it's generally trivial to find the relevant part of the target page with your browser's search function. In some cases it might help to add a little bit of text to the citation saying how to reach the relevant info. Sure, putting stuff on wikisource is good if the material is suitable and free. It's still not appropriate to route the urls through those annotation services, because the click stream exposes user's reading habits to an unnecessary third party. If annotation became important it might be ok to run an annotation engine as a Wikimedia service directly on a Wikimedia-operated server, but that's different, and in my opinion not very likely to happen anytime soon. I guess it might be possible to have some javascript in the new Wikipedia UI (try the beta site) that did some annotation effects as layers. I'm not sure if that could be done without accepting a browser download though, because of browser restrictions designed to prevent XSRF attacks. Maybe I'll ask a web coder about that sometime. 66.127.52.47 (talk) 07:27, 27 March 2010 (UTC)

Ubuntu 9.10 Monitor Hibernating without Consent (revisited)

Sorry to revive an old-ish question, but the answer I got for this told me what I should do and not how I should do it. After I asked how, the question was archived. Now, I've been advised (specifically by User:Nimur) that I may have my monitor sleep settings set differently from the rest of the computer, and that I should consider resetting them to my desired configuration (if there is such an option). Now, what I want to do is have the computer never go to sleep, never switch off, nor, in fact, ever do anything which does not involve me actually pressing a button. Short and tall of it is, how do I stop my laptop from going to sleep after five minutes when I have not touched it, and I have all of my power settings on 'Never'. I would link you to the previous time I asked the question, but Chrome has the pointless habit of just downloading me a PHP file every time I click on diff links on Wikipedia, so I can't, sorry. Any help, in terms that can be understood by someone who really doesn't know what to do (<-this is important), would be very much appreciated. --KägeTorä - (影虎) (TALK) 14:46, 26 March 2010 (UTC)

Are you using GNOME (default Ubuntu DE), or something else?
If you want fast help with things like this, checkout the #ubuntu or ##linux channels on irc.freenode.net*. ¦ Reisio (talk) 16:16, 26 March 2010 (UTC)

I am in fact using the default Ubuntu desktop environment. I will check out the IRC channels some other time on my Vista computer (this Ubuntu one does have a habit of switching off even when I am doing stuff on it - also, I will need to download and install a chat client on the Vista). --KägeTorä - (影虎) (TALK) 16:34, 26 March 2010 (UTC)

http://webchat.freenode.net/ http://silverex.org/ ¦ Reisio (talk) 17:07, 26 March 2010 (UTC)

After re-reading KageTora's original post, I think it's unlikely that my monitor diagnosis was helpful. It seems like the problem is actually with the operating system, or the computer hardware. I'm not really sure if we have enough information yet to diagnose what's causing this hibernation problem. Nimur (talk) 22:20, 26 March 2010 (UTC)

How is bookmarks.html read by Firefox?

Resolved

I don't see the URLs of my bookmarked sites there, but I see long lines of text like iVBORw0KGgoAAAANSUhEUgAAABA... which I assume is my bookmarks encoded in some way. What is the encoding used there, or in other words, how do those long lines of text get turned into my URLs and human readable descriptions when Firefox is running? I searched through all the subdirectories in the Mozilla Firefox directory on my computer for files containing the text of my bookmarks, but no files were found. That seems to tell me the information regarding my bookmarks is not in another place than bookmarks.html.Thanks. 20.137.18.50 (talk) 17:36, 26 March 2010 (UTC)

I don't know about you, but I *do* see my bookmarks in there. The long strings appear to be base64 encoded icon information corresponding to the bookmark. The icon data is much longer than the bookmark URL, so you might not be seeing the URLs scattered about in there. —ShadowRanger ^(talk|stalk) 17:42, 26 March 2010 (UTC)

It's possible you may be looking at the wrong bookmarks.html, particularly if your computer has been through many Firefox upgrades. I believe they slightly changed the organization of the config data, and an old, possibly empty version might be left in the original location. Mine is in my %USER%\Application Data\Mozilla\Firefox\Profiles\WEIRDPROFILEIDSTRING.default (obviously, your WEIRDPROFILEIDSTRING will differ). This will be slightly different on a Vista/Win7 machine ("%USER%\AppData\Roaming" instead of "%USER%\Application Data" I believe, though I'm on a weird corp system right now, so your mileage may vary). And of course it will differ even further on a *NIX box or a Mac. —ShadowRanger ^(talk|stalk) 17:48, 26 March 2010 (UTC)

Yeah, that one had all my bookmarks information. Thanks. It makes sense now because I was looking in bookmarks.html over in Program Files\Mozilla Firefox\defaults\profile. 20.137.18.50 (talk) 18:15, 26 March 2010 (UTC)

Just to wrap up, virtually no applications keep their user config data in the Program Files directory anymore. It was strongly discouraged pre-Vista, and when Vista released, programs that were still doing it started breaking, or triggering elevation prompts (because writing to the Program Files directory is Admin-only), which annoyed the hell out of users. Nowadays, most apps still being supported use the per-user AppData directories properly. —ShadowRanger ^(talk|stalk) 22:42, 26 March 2010 (UTC)

March 27

Using Twitter for business

Hi, I am a manager for a company and have been given an "official" twitter account. I was wondering if it was possible--through some third party or whoever--if I can set it up to post tweets to the one account from my employees' personal cell phones as they are scattered about. It would have to be something I can control from my end, so I can deauthorize any one employee from twittering if I need to, and also without giving them access to the account itself through the username and password. Thanks! 68.63.212.186 (talk) 01:53, 27 March 2010 (UTC)

http://cotweet.com/ F (talk) 06:05, 27 March 2010 (UTC)