Wikipedia:Reference desk/Archives/Computing/2011 February 17

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February 17

Generic DVD/RW software for Win XP

I've just got myself an Acer Aspire netbook, and am trying to persusade it to recognise an ancient external Freecom classic series DVD/RW. I know I looked some time ago for software/drivers for this, but couldn't find any - eventually, I found a generic driver somewhere, but I haven't a clue where. Does anyone know where I can find one?

The netbook recognises the DVD writer as a CD drive only at the moment, but I've definitely had it working before - unfortunately, this was on my desktop PC, which seems to have given up the ghost, so I can't see what software I was using :( AndyTheGrump (talk) 01:51, 17 February 2011 (UTC)

Scratch that: It seems to recognise the DVD/RW now, or at least, it reads DVD's ok - I think I'll need to find DVD writing software, but that is less urgent. AndyTheGrump (talk) 02:45, 17 February 2011 (UTC)

One free option for the software is CDBurnerXP (if you're using pretty much any version of Windows) which burns onto CDs, DVDs, etc.  ZX81  ^talk 12:15, 17 February 2011 (UTC)

Another alternative is Infrarecorder, which is free. -- Finlay McWalter ☻ Talk 15:20, 17 February 2011 (UTC)

Thanks, I'll take a look at both - Infracorder sounds familiar, that may have been what I'd been using previously. AndyTheGrump (talk) 20:54, 17 February 2011 (UTC)

There is also ImgBurn. Reviews are here: http://www.techsupportalert.com/best-free-cd-dvd-burning-software.htm 92.24.182.65 (talk) 21:45, 17 February 2011 (UTC)

How do I save an LUA file as an LUA file in Vista?

I want to edit a small lua file for an RTS mod that I play, but Vista brings up an error message something along the lines of "cannot specify path or make sure specific path is correct" every time I try to save the edited file. Even when the file is unedited it won't let me save. I just want to edit the lua file and save it, how can I do that? --Ye Olde Luke (talk) 04:47, 17 February 2011 (UTC)

Are you able to get to the Save As dialog where you can specify a save location? Does it allow you to save in the Documents folder or on the desktop? I know lua files often have to be saved in a sub-folder of the game's application folder (sorry, the technical term has deserted me!). Vista can be very protective of folders under Program Files, and I often had to save my addon files elsewhere, moving them to the correct folder as an admin user afterwards. --Kateshortforbob _talk 13:18, 17 February 2011 (UTC)

Drive size increases after copy then delete files

Okay. Just make it simple with a small example. This morning I move 25 GB of data from D: to E: before formatting D:, to get rid of some garbage files created by the Windows System Image that I cannot see (even if system hidden file are shown). After everything is done, I move those data back. Now the E: drive size increases by 47 MB. 47 MB is not too serious for me, but I really want to know where and why it is gone. Not only this morning, I have seen that phenomenon for several years w/o a reason. Only when I format the drive, the wasted space created by deleting files is restored. If I remember correctly, this does not happen on drive with FAT32 file system. My flash drive for example; its size always changed to 4096 bytes each time I deleted all data on it. -- Livy the pixie (talk) 08:12, 17 February 2011 (UTC)

If I were to hazard a guess I would say that the space was used up by Windows Advanced Indexing which didn't clean up the newly allocated space once the files were deleted again. You can turn indexing off if you really want, but I wouldn't recommend it as that feature is used to improve the speed and stability of your system. It's also possible your page file could have increased in size. Sandman30s (talk) 10:38, 17 February 2011 (UTC)

No, I use no page file at all. I would like to used raw RAM because I think it is faster, and my computer RAM is large enough to be used without page file. I have heard a thing or two 'bout the Indexing thing but maybe I need to study it further. Just googling around, but 'till haven't found the answer yet. Btw, anyone can try copy about 1 GB data or larger to a drive and then delete it to see the result. -- Livy the pixie (talk) 10:55, 17 February 2011 (UTC)

The Master File Table has a 1-kilobyte entry for each file on the disk. It's expanded as necessary and (I believe) never shrunk. If you moved 48,000 files or so, that could be the explanation. Later files created on the volume will reuse those MFT entries. -- BenRG (talk) 11:20, 17 February 2011 (UTC)

Personally I think you should not worry about any of this. In an era when 2TB drives cost US$80 or US$90, why get all OCD about the issue to the point where you are actually formatting drives to try to reclaim an amount of space that is tiny by today's standards? You should also use a page file, by the way; it shouldn't slow down your system in your case. Comet Tuttle (talk) 17:42, 17 February 2011 (UTC)

Windows XP had/has an annoying habit of discarding perfectly good pages when the system is idle even when there's no memory pressure. I often had the experience of leaving my computer to get a cup of coffee, returning, and having to wait several seconds while the stupid thing paged in the application I had just been using. I disabled the swap file and the problem went away, with no apparent downside. This might be fixed in Windows 7; I don't know because I've never attempted to use a swap file in Windows 7. RAM is cheap too... -- BenRG (talk) 21:12, 17 February 2011 (UTC)

This page at Coding Horror hosts part of a fierce debate on this issue. One somewhat obscuring fact is that Windows 7 is a very active disk cacher and whatever RAM you have that is unused will rapidly be used for disk cache, which may make measurements harder. Personally I would always choose to have a disk cache, even a 1 byte disk cache, if it were feasible, because I would prefer to never ever seen an "Out of Memory" error again in my whole life; having disk cache on simply prevents this. (Obviously by growing my 1 byte page file to whatever size was needed, when it was needed.) And if you've got so much RAM, your OS should never be hitting the page file anyway. If, as you say, the OS behaves itself well. Comet Tuttle (talk) 21:25, 17 February 2011 (UTC)

I disabled it because I hate the way Windows manage page file. If you had 2 GB RAM, it set the page file to 2 GB, and if you had 4, it set the page file to 4 (logically it must set the page file smaller because you have more RAM). I encounter no issue on my desktop with 4 GB RAM but my laptop with 2 GB RAM crashed when I opened 8 → 10 tabs on IE silmutaneously, so I was forced to set it to 1 GB. -- Livy the pixie (talk) 04:07, 18 February 2011 (UTC)

It doesn't necessarily follow you need a smaller page file if you have more RAM. In fact, logically, if you have more RAM, there is more stuff that may be worth swapping out so a larger page file makes sense Nil Einne (talk) 13:17, 19 February 2011 (UTC)

Windows has two sizes for files - the actual number of bytes in the file, and the space used on disk. Depending on file, sector and cluster sizes there can be quite a discrepancy. If a disk has 1024 byte clusters, then a 1025 byte file will consume 2K of disk space, even though Windows will still report that it is a 1025 byte file. If you delete that file, then the free space on the drive will be (previous free space + 2K). --LarryMac | Talk 20:22, 17 February 2011 (UTC)

That's true, but it can't explain the missing 47 MB. -- BenRG (talk) 21:12, 17 February 2011 (UTC)

There's a general trend in the design of computer systems to build things that have more and more nice properties (reliability, good performance in corner cases, etc.), at the expense of predictability. FAT32 is not a journaling file system, so it's simpler in behavior, but breaks more and worse. Paul (Stansifer) 20:53, 17 February 2011 (UTC)

Almost forgot. If you deleted a single 7.8 GB DVD9 ISO image, the drive size increased only by a few bytes. But if you deleted several thousands files with total size of 500 MB, the drive could waste up to 10 MB (Approximately. The point is that the more files are deleted, the more space is wasted. The wasted space does not depend on the file size, but on the number of files). Oviously 47 MB is too tiny by today standards, and I do not format the drive to recover it. Just because I want to know why it vaporizes into thin air. -- Livy the pixie (talk) 04:07, 18 February 2011 (UTC)

If it's ~1K per file, then it's probably the MFT (see above). -- BenRG (talk) 06:33, 18 February 2011 (UTC)

It sounds logical. But are you sure later files created on the volume will reuse those MFT entries? -- Livy the pixie (talk) 08:08, 18 February 2011 (UTC)

WYSIWYG Wiki Editor

Is there WYSIWYG Wiki Editor that can be used in a web browser to create/edit, even in offline and later submit to Wikipedia?

There was a big effort to do something like that in browser Javascript but I don't know its current status. I just write wikitext in emacs (i.e. so I see the markup, not wysiwyg) and it works fine. Wysiwyg is overrated unless you have no experience with wiki markup. 71.141.88.54 (talk) 11:41, 17 February 2011 (UTC)

Wikia.com uses a wysiwyg editor. I hate it. I refused to use wikia until they offered an option to turn off the wysiwyg editor, allowing users to use wiki markup. -- kainaw™ 13:40, 17 February 2011 (UTC)

Kaspersky Internet Security fouling up my devices

I recently plugged my Archos 28 Internet Tablet into an XP computer running Kaspersky. Kaspersky decided to wipe all the data from the device because it was allegedly a virus. I got it all restored, but it started behaving rather oddly; the folders wouldn't display a "folder" icon but instead a 'unknown file type' one. They'd always open in a new window. Now it won't let me add or delete files on other systems because the disk is "write protected," and something similar's also happened with a SanDisk Cruzer Blade USB stick I've been using.

What can I do? 122.174.98.39 (talk) 11:57, 17 February 2011 (UTC)

Well, an obvious thing to try is to uninstall Kaspersky and install some different antivirus software, and see if that fixes your problem. List of antivirus software is a good starting place. Comet Tuttle (talk) 17:39, 17 February 2011 (UTC)

Graphics/visualization question: converting vector field samples into continuous streamlines

Say you have a 2-D vector field sampled regularly at grid points. How do you convert the samples into continuous streamlines(?) for visualization? Thanks in advance. --173.49.19.81 (talk) 12:57, 17 February 2011 (UTC)

Are you asking for a "general solution" or a specific software program that can do this? Here is software to draw arrows in FORTRAN90, in MATLAB using the quiver command; in the free software GNU Octave you can also use quiver. If you want streamlines you must numerically integrate the ordinary differential equation whose gradient is expressed by the vector-field; and iterate over initial-values for each streamline you want to solve. This is a bit tricky, because in pathological cases the solutions will be unstable (and streamlines will cross - which is an unphysical result). For this reason, you should not use a simple forward-difference integrator (like an euler method) - though you can try, and see if it works. In MATLAB, you can use ode23 or the other sophisticated higher-order Runge-Kutta methods to stably integrate most vector fields. In FORTRAN-90, you can use your favorite numerical solver code, such as this RK-45 solver from Iowa State University. To make matters more complicated, if (as you say) you have sampled the vector field (and cannot explicitly calculate it at every point) you must interpolate the values between sample-points so that an integrator can solve the streamline. The method you choose for interpolation can influence stability and convergence, not to mention physical interpretation of the streamline. If you are lucky enough to have MATLAB, you can use the Streamline program to perform all of these steps for you. I do not believe GNU Octave supports this command yet ((streamline) is reported "unimplemented" still). For obvious reasons of complexity, it is non-trivial to implement this in general. Nimur (talk) 20:47, 17 February 2011 (UTC)

Valve holder tax

In the Radio receiver design#FM vs. AM article there is mention of an "valve holder tax" that the UK goverment imposed. What were the reasons behind this tax?, and time period? I did some net searches, but no qualified answer were found. Electron9 (talk) 13:12, 17 February 2011 (UTC)

The reason behind this tax was simply to raise revenue. No different from the Hearth tax, and Window tax. People who choose to have more than fire place, or think they 'need' more than one window, or even have a radio with more than one thermionic valve socket, obviously have more money than sense! Therefore, their government obliges them to pay even more for the said items. With the money so collected, those who have the onerous duty to run the country, can then spend the money more wisely - on such things as foreign visits, commissioning statues of themselves and cultural enriching things that the tax payers themselves are not capable of appreciating. Germany imposed a similar tax.Vacuum_tube#Other_variations. Simple really.--Aspro (talk) 20:55, 17 February 2011 (UTC)

Which time period?, and how muchdid the goverment charge?, used other countries? Electron9 (talk) 10:17, 18 February 2011 (UTC)

Aspro: do you have any evidence that the UK valve holder tax was intended to raise revenue and not e.g. to fund radio services?

I can't find any evidence that there was a valve holder tax in the UK. Googling "valve holder tax" returns only pages that scraped that Wikipedia page. I found a discussion that explained that sales tax was payable on valves for home use in radios but not for commercial/industrial use in other products; this is consistent with having a tax on finished products but not on raw materials or components (the current UK value-added tax uses a different system to the same end.)[1] However, early 20th century taxation policy may not be well documented online, so it's possible the tax did exist for a while.

Regardless of the valve-holder tax, the UK had a radio tax in the mid 20th century (1922-71) which was used to fund the BBC: you had to buy a radio licence to own a radio in the UK. In the earlier years, a licence for a home-made radio was more than that for a pre-built radio bearing the BBC brand (again this may have been transformed into memories of a tax on valves). There was an additional tax payable on the licence from 1957 to 1964 which went to central government, but most of the time all the money went to the BBC. The licence is briefly mentioned in Television_licence#United_Kingdom but my main source is[2]. --Colapeninsula (talk) 10:38, 18 February 2011 (UTC)

Home brewed radios were certainly more expensive to build from purchased parts. One had to buy the components as if they were spares (and also pay purchase tax on the higher prices). Even from a wholesaler willing to give a discount off the list price, it would still cost a little bit more. Still, if one just bought the valves, most of the other bits could be scrounged or made in garden shed for naught. --Aspro (talk) 18:15, 18 February 2011 (UTC)

Crossword puzzle generators

Resolved

Hi, I'm wondering about crossword generation software, preferably for Windows (but Linux is fine too, as long as it has a GUI) and definitely not online. I used to have a program on my old Mac OS 9 machine (archaic, I know), that did exactly this but I can't remember what it was called. It updated the puzzle as you were typing, so you could see the layout of the puzzle while you were making it. Thanks :) XRDoDRX (talk) 14:45, 17 February 2011 (UTC)

I use Crossword Compiler. I think it only has British English but I could be wrong and it might not matter that much depending how you want to use it. There are others available if you search the web.--Shantavira|^{feed me} 16:17, 17 February 2011 (UTC)

I found a free one called EclipseCrossword. Sometimes I wish Windows software was sorted into packages, it would be much easier to find the good stuff. XD --XRDoDRX (talk) 03:22, 20 February 2011 (UTC)

Keyboard/start-up problem

I have a Dell Latitude D620 laptop and run Windows XP that requires me to do a control-alt-delete after a start-up. The problem is that when I press the control-alt-delete buttons, nothing happens and I can't get use the laptop. Obviously, I'm on another computer now. Does this mean that I have a bad keyboard, or is there something else I can try? Thanks for any help. 71.125.146.152 (talk) 16:05, 17 February 2011 (UTC)

A few things to try

• Do the other Ctrl-Alt-Del keys work? Either the left or right Ctrl and Alt keys, and either the Delete or NumPad Del keys will normally work.
• Does an external USB keyboard work?
• Do the NumLock/CapsLock keys work?
• Try pressing F6 after the BIOS screen clears; you should drop into the Windows Boot Loader; does Ctrl-Alt-Del reboot the laptop here?

CS Miller (talk) 16:22, 17 February 2011 (UTC)

Thanks for the quick reply. I tried those options, and none worked. I was finally able to get through to my employer's IT people and was told the keyboard is not functioning because I can't even start up before Windows begins running. They're sending me another. Again, thanks for your help.71.125.146.152 (talk) 16:53, 17 February 2011 (UTC)

What you can try is to power off the PC. Take out the battery and the cord and hold the power button for a minute. That resetted the keyboard for me when it was not working. --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 21:14, 17 February 2011 (UTC)

This sounds like you've run into a rather common problem with the Dell D-series laptops...I did tech support for C-Series and D-series laptops for a couple of years, I've seen that issue countless times. The problem is that the keyboard connector on the motherboard is just badly engineered and the cable will occasionally come off. The easy fix is to remove the keyboard (there are a couple screws marked with "K" for keyboard on the back, just unscrew these and you can lift off the keyboard), then unplug and firmly reseat the keyboard cable. If you haven't sent it off to your support people yet, that's definitely something you should try. -- Ferkelparade π 09:18, 18 February 2011 (UTC)

IBM Watson

Is IBM Watson an OS or just a program running on an OS? --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 20:56, 17 February 2011 (UTC)

We have an article on Watson (artificial intelligence software), although it doesn't answer this question directly. Personally, I'd say that Watson is an application running on specially configured hardware, and most likely running a customized version of whichever OS IBM typically supplies with the Power7 hardware. --LarryMac | Talk 21:04, 17 February 2011 (UTC)

This type of diagram may be misleading you.

I thought WATSON was an OS since only an OS has direct access to all the hardware components --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 21:11, 17 February 2011 (UTC)

The article does answer this directly — Watson runs on the SUSE OS. It's an application. Why would you assume Watson needs "direct access" to any hardware component? Comet Tuttle (talk) 21:12, 17 February 2011 (UTC)

Damn, I read right past that at least four times. My bad. --LarryMac | Talk 00:01, 18 February 2011 (UTC)

Because than it can harness the raw power of the CPU and graphic chips (assume WATSON has one) --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 21:15, 17 February 2011 (UTC)

I think that diagrams like the one to the right (which I found in our operating system article) may be misleading you a bit. It's true that an OS is allowed to execute certain CPU instructions that an application is not allowed to execute, but the CPU still directly fetches each instruction in the Watson code and executes it directly, and stores the results directly into memory. Being an OS wouldn't speed up Watson any more. Comet Tuttle (talk) 21:34, 17 February 2011 (UTC)

If the machine has special hardware designed for your application (which Deep Blue certainly did, but I don't know about Watson), one does normally need kernel privileges to use it, but the usual practice is to write most of the software as a normal application, except for a small device driver that runs in the kernel and passes application data to the hardware and vice versa. -- BenRG (talk) 22:55, 17 February 2011 (UTC)

Operating systems don't possess any inherent power that applications don't have. They can deny powers to applications (if the user so desires); this is useful for security. But it's best to think of the operating system as an abstraction layer: it allows each program to run as though it were the only program running on the machine, and without having to know the details of the particular machine. Even though the Watson software was purpose-built for one machine and that machine had only one use, it turns out that writing software in this way is much easier than writing it without an operating system, because the imaginary simple machine that the OS presents to the applications is nicer than the real machine. Paul (Stansifer) 05:11, 18 February 2011 (UTC)

There's nothing magical about operating systems. They're just programs like applications are. The only technical difference is that they run directly on the hardware, but it's actually technically possible to run any program directly on the hardware. Today's computers are so complex that writing an application running directly on the hardware is quite difficult compared to writing one running on an operating system, but in the past, it was common to write custom programs that ran directly on the hardware. The answer to the original question is that WATSON is most probably an application running on an operating system. JIP | Talk 08:15, 18 February 2011 (UTC)

A technical whitepaper is available from IBM at http://ibm.com/watson - you may need to create a free IBM-login if you don't already have one. Watson is written in Java - so technically, IBM Java Runtime Environment is the "operating system," though the IBM JVM resides on top of IBM Linux on IBM Power7-750 systems, with a variety of other IBM and free/open-source software. For example, the Hadoop and Apache UIMA technologies make the system work as a whole. With clusters of computers, it's often difficult to describe "operating system" in terms that the average PC-user will quickly understand (because - it isn't exactly clear if the "computer" is distinct from the "ensemble of computing nodes" - especially if each node is a fully-capable computer on its own). If I were to describe the OS, I would say it is "Apache httpd, plus the IBM J2EE environment." I would not include Linux as a description of the operating system of Watson, because he could be trivially ported to any other computer platform that supports Apache and J2EE. In the case of the machine we saw on television, "Linux" is really just a very sophisticated device driver for a handful of CPUs and a little bit of RAM; the operating system is the Java environment that harnesses hundreds of Linux devices and assigns tasks to them. Nimur (talk) 16:53, 18 February 2011 (UTC)

WATSON interface

What does IBM WATSON GUI looks like? Also I read in the comment that WATSON crashed during the games. Is this true? --Tyw7  (☎ Contact me! • Contributions)   Changing the world one edit at a time! 23:13, 17 February 2011 (UTC)

There may not be one. Watson's job is to consume a chunk of text and produce another chunk of text. Programmers are used to working with command line programs, and Watson's task fits that ideally. Of course, there's a great deal of complexity between input and output, and we can only speculate on all of the diagnostic and control tools that the engineers had access to. A software project like Watson probably has a single large piece of software and a cloud of (partially) independent tools. Each of these can be operated by a human, and probably some of them allow a person to drive the whole thing in a simple way (useful if some person comes visiting and wants to see a demo, instead of the charts and graphs and benchmarks that the engineers have been staring at for weeks as they struggle to improve the system).

I hear the rumor that Watson kept on crashing during the game, also. It seems odd to me because IBM's researchers clearly know how to write software, and the problem probably lends itself to a (relatively) stateless (and perhaps even nicely modular) design, which would make it easy to write reliable code. But I don't know anything about the problems they faced. Paul (Stansifer) 05:39, 18 February 2011 (UTC)

Where does that rumor come from? IT seems like no one outside of IBM would actually know that. APL (talk) 06:13, 18 February 2011 (UTC)

It might be a throwback to the Kasparov match. One of the criticisms of Deep Blue was that the programmers manually altered the system between matches to incorporate fixes to defects discovered during play. The fact that the rumor takes off could be feeding off of that, with the thought that "well, the computer didn't really do it on its own, it needs constant attention of people to work". Sort of a pro-human/"humans *aren't* obsolete" ego boost. Pretty much the same reasoning behind the criticisms that the match wasn't fair because Watson got the clues in the form of a text message instead of having to do audio processing/OCR of the monitors. -- 174.21.250.120 (talk) 18:04, 18 February 2011 (UTC)

I don't think it's a rumor. My understanding is that the PBS people filming the game encountered frequent delays because of problem with a computer. They incorrectly assumed that it was the IBM machines running Watson that was at fault, but later clarified that it was actually the computer that passes the questions to Watson. Predictably, the press ran the story without doing any research into whether it was true or not. On a side note, the cluster running Watson is built from Power 750s. If they are like earlier models, restarting them after a crash is not a trivial matter as it is with PCs, its an approx. 30-minute affair due to diagnostic checks. Rilak (talk) 07:27, 18 February 2011 (UTC)

It's also worth noting that IBM software is, unlike many commercial "consumer" tools, usually subject to extremely high uptime requirements. Now, Watson was a research project, but he was still designed in the same environment. During my (brief) time at IBM, I recall the motto, "high performance, high uptime, high availability," in reference to our computers and our engineers. You can read about High Availability Services at IBM's website. Mean time between failure is often quoted in years or even decades. (Again, let me re-emphasize - this is not your average Windows PC). It sounds very dubious that the software, hardware, or anything else, would crash during the game show. What I might believe is that "performance degradation" occurred as a result of software or hardware error, but IBM Tivoli restarted the derelict server software. (Another thing I learned from IBM is that there's no such thing as a "crash" or a "failure"...) Nimur (talk) 16:35, 18 February 2011 (UTC)

Regarding the GUI, it is probable that Watson uses the IBM variant of the Eclipse platform. IBM uses Eclipse to develop and to deploy almost all of its software. It is very likely that an Eclipse plugin communicates to a set of IBM server-utilities to monitor status. Nimur (talk) 16:39, 18 February 2011 (UTC)