Wikipedia:Reference desk/Archives/Computing/2007 October 29

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October 29

High level programming languages

Are there high level programming "languages" now based entirely upon selection and arrangement of symbols, such as some neural networking programs that not only can generate code based on selection and placement of nodes (functions) and connections(weights) but can select and place nodes and connections based on input and output training values, formerly used only to train the network's weights? Clem 03:48, 29 October 2007 (UTC)

I seriously doubt it. It wouldn't lend itself to the fundamentally linear processing model of computer processing- it would be a bad idea to try to write code like that. But I wouldn't be surprised if neural networking programs allowed you to run scripts on top of your neural nets- that's probably your best shot right now, a hybrid solution --ffroth 23:35, 29 October 2007 (UTC)

Home lan

I have a Broadband Modem that supports simultaneous USB and LAN connection.Can it be configured for Home network between computers??~~

Yes, presumably if a modem has an ethernet port it would have a built in router and in that case you can simply buy an ethernet switch to connect them together.

Well I was wondering wether I could have a Lan without investing in a Hub.The Modem assigns different gateways to both devices.Is it possible to make it assign only One gateway address?~~

What is smart cursoring in MS Word?

Hi,

I want to know what is smart cursoring in MS Word? —Preceding unsigned comment added by 210.18.82.102 (talk) 08:57, 29 October 2007 (UTC)

• A Google search for smart cursoring reveals all. --Sean 16:04, 29 October 2007 (UTC)

Customisations in Word and Firefox

Hi, I would like to know if it is possible to transfer the various customisations I have made in both Word and Firefox from one machine to another. In Word the customisations are things like AutoCorrect entries and macros. In Firefox they are mainly bookmarks. Many thanks. --Richardrj ^{talk email} 09:06, 29 October 2007 (UTC)

• If it's just bookmarks, you can export and import them through the bookmarks manager: look under your bookmarks menu for "Organize bookmarks" or something similar. Once the bookmarks manager opens up, look under your file menu for export and import.
• If you want to transfer almost everything, http://www.mozilla.org/support/firefox/profile has details. --Kjoonlee 17:52, 29 October 2007 (UTC)

Thanks very much. Any idea about Word? --Richardrj ^{talk email} 18:06, 29 October 2007 (UTC)

Channelize my RAM

I am working with Windows Vista and my laptop has 1 GB RAM ... however, I cant play games such as Fifa 08 and NFS Most Wanted properly although the full memory is not utilised. How can I channelise my RAM towards such games ... ???

Please advise. —Preceding unsigned comment added by 125.17.38.10 (talk) 13:23, 29 October 2007 (UTC)

1GB is plenty for these games, even with vista running. The operating system will make sure the programs get the memory they need, there's no need to manually "channelise" memory to a particular process. However, you can help free up memory by closing any other programs you have running, including browsers, IM clients, and antivirus software. But chances are you can't play those games because of deficient CPU power (upgrade your cpu) or because your video card chipset isn't supported (upgrade your gpu) --ffroth 16:57, 29 October 2007 (UTC)

are you serious, froth? I would never upgrade my cpu on a laptop. --Kushal^t 19:07, 29 October 2007 (UTC)

Oh it's easy to upgrade the CPU on your laptop, just take everything out, take the CPU out of its socket if it uses sockets, pop the new one in, and put everything together again. If it's soldered on just get a heat gun and melt all the solder, remove it, and pop in a replacement which you've previously acquired. --antilived^{T | C | G} 19:11, 29 October 2007 (UTC)

Oh I missed that it was a laptop. Yeah, probably a bad idea to try- unless you're absolutely sure that the new processor will fit. The first generation merom uses the same socket as my yonah, but I don't think it actually physically fits inside the giant heat pipe system running through my laptop, even if I could get in there. And a GPU upgrade is out of the question. But that's what you probably need to play the games *shrug* --ffroth 19:37, 29 October 2007 (UTC)

Vibrator Overclocking

If i wanted to go about overclocking the vibration function on my 2004 built N-Gage QD how would I do that? —Preceding unsigned comment added by 78.147.220.128 (talk) 20:04, 29 October 2007 (UTC)

Didn't they do that on an episode of The IT Crowd, or something :)? I don't know if the N-Gage allows you to flash a new firmware on it (which could possibly accomplish this), but even if it did, rewriting the firmware in order to allow it to do this is almost certainly a seriously difficult and major project (and if the vibrator has some hardwired limit on how much if can vibrate, even this wouldn't work). If you're a genius and isn't doing anything for the next couple of months, maybe you could get it done, but I doubt it. This is an idea you should put into "It would be so cool if...!" file and just forget about it because it ain't gonna happen --Oskar 20:17, 29 October 2007 (UTC)

Well it should be possible to do this electronically. I mean it's obviously possible (though not necessarily easy)- how else do CPUs run in the GHz when the FSB clock is only around 100mhz? I'll tell you: with a frequency multiplier. Shouldn't be too tough to wire one of these babies in, though it's true I have no idea how those vibrators work- the electronic oscillator might be closed within the vibrating unit --ffroth 23:31, 29 October 2007 (UTC)

Most vibration units are a simple electromotors that spins a bit of mass around (which is attached 'off centre' to the driveshaft, so the the whole system shakes). Like when you swing a stone around by a rope, the inertia pulls on your hand. If you don't provide a counterforce to keep your hand stable, the stone pulls on your hand as much as your hand pulls on the stone and the whole setup 'vibrates'. This means that there's probably no electronic oscillator, just a current to the electromotor. I suppose the current does need to be alternating for the electromotor to work, but changing that'll mess up your motor. You could increase the weight, which would increase the amplitude of the oscillation, and reduce the frequency. Or reduce the weight to do the converse. Of course, this would just change the feel of the vibration, not the actual energy. I think your best bet by far is to locate the vibration unit, and replace it with a stronger one (and be prepared to sacrifice battery life). risk 01:14, 30 October 2007 (UTC)

Also see our Vibrating alert article.

Atlant 11:44, 30 October 2007 (UTC)

Scanned handwriting

I want to know if there is a program that I can use to take scanned handwriting and turn it into the text on the computer like this? Wanda —Preceding unsigned comment added by Wanda Church (talk • contribs) 20:12, 29 October 2007 (UTC)

There are many such programs. See optical character recognition. Algebraist 20:21, 29 October 2007 (UTC)

One that a normal person can download free? --Wanda —Preceding unsigned comment added by Wanda Church (talk • contribs) 20:43, 29 October 2007 (UTC)

Several of the programs listed there are available for free download. Algebraist 20:54, 29 October 2007 (UTC)

They are all something like .tar.gz and I can't open them. The other ones cost money. comment added by Wanda Church (talk • contribs) —Preceding comment was added at 21:23, 29 October 2007 (UTC)

This page (from Google) explains how to extract .tar.gz files on every system I've heard of and a great many I haven't. Algebraist 22:06, 29 October 2007 (UTC)

The correct answer is no, learn to type. As the article says, hand printed text scanned from paper is difficult to recognize, and cursive writing is an unsolved problem. Almost certainly it will be a waste of your time to download, install, and learn to use any of these programs, then hand correct all the errors in recognition that will surely result. Even if you can only learn to touch type at 30 words per minute, you're likely to be faster and more accurate than OCR software. --KSmrq^T 22:51, 29 October 2007 (UTC)

If you don't like typing, and you have a lot of pages, you must like proofreading. I am sure no OCR software will guarantee 100% accuracy. I wonder what Google Book Search does. --Kushal^t 17:36, 30 October 2007 (UTC)

Windshield Wiper Animation

Hello. In Turing (programming language), I am trying to make windshield wipers move as how windshield wipers move on cars. So this is my source code,

   %Windshield Wiper Animation
   loop
       for decreasing x : 320 .. 0
           drawline (160, 0, x, 160, black)
           delay (1)
           drawline (160, 0, x + 1, 160, white)
           delay (1)
           drawline (480, 0, x + 320, 160, black)
           delay (1)
           drawline (480, 0, x + 321, 160, white)
           delay (1)
       end for
       for x : 0 .. 320
           drawline (160, 0, x, 160, black)
           delay (1)
           drawline (160, 0, x - 1, 160, white)
           delay (1)
           drawline (480, 0, x + 320, 160, black)
           delay (1)
           drawline (480, 0, x + 319, 160, white)
           delay (1)
       end for
   end loop

How can I make my windshield wipers move in a "semicircular-like" motion? I know very little about the drawarc function and I do not know how to apply it here. Thanks in advance. Sorry for any inconvenience. (I do not know how to condense my source code with this "Show" thing.) --Mayfare 20:55, 29 October 2007 (UTC)

Maybe with trigonometric functions, or with the equation for a circle? Try something like this to move a line in a partial semicircle like windshield wipers. The semicircle is 10 units in radius.

for x from 0 to 15
draw line from 10,10 to x,Sqrt(10^2 - x^2)
end

And to make another one 30 units to the right at the same time you just throw another command in the middle like this:

for x from 0 to 15
draw line from 10,10 to x,Sqrt(10^2 - x^2)
draw line from 40,10 to x,Sqrt(10^2 - (x-40)^2)
end

I think that's right. And all that is assuming that 0,0 is the top left of the screen and the first value measures horizontal distance and the 2nd value measures vertical. In other words, standard. Which is pretty much Turing in a word, unless you want to use the word "useless" --ffroth 23:25, 29 October 2007 (UTC)

I suspect your drawing will look MUCH nicer if you restructure your loops:

   loop
       for decreasing x : 320 .. 0
           drawline (160, 0, x, 160, black)
           drawline (480, 0, x + 320, 160, black)
           delay (1)
           drawline (160, 0, x, 160, white)
           drawline (480, 0, x + 320, 160, white)
       end for
       for x : 0 .. 320
           drawline (160, 0, x, 160, black)
           drawline (480, 0, x + 320, 160, black)
           delay (1)
           drawline (160, 0, x, 160, white)
           drawline (480, 0, x + 320, 160, white)
       end for
   end loop

(This will stop the animation from being quite as flickery as it presumably is right now - and also make the animation go 4x faster, if that's a problem then change the delay(1) to a delay(4) or (better still) step the loop in jumps of 0.25 instead of 1.) The idea with animation is that you want to draw the wipers, give a little bit of time for the user to see them in that position, then very quickly, erase them and redraw them again in their new position.

As for making the wipers animate along a curve - I'm not sure what Froth is trying to get at here (but it's wrong!). You need x to be the angle of the wiper blade and that means you need to use some trig. Something like

    drawline(160,0, 160.0+320.0*sind(x), 320.0*cosd(y), black)

I don't know enough 'Turing' to know how it does floating point (er "real") numbers and I suspect that 'sind/cosd' accept angles in degrees...but I'm sure you get the idea.

And yes, I'd also feel an urgent need to construct a short sentence containing the word "Turing" and the word "useless" - perhaps with another small word like "is" in the middle. Jeez - why are they teaching this useless language? They should be teaching Java. It's a better language, it's free so you could practice at home - and it's actually useful for something so you don't have to spend another year 'unlearning' Turing. Alan Turing must be rolling in his grave in the knowledge that such a crappy language was named after him! Argh! SteveBaker 22:09, 30 October 2007 (UTC)

How is it wrong :/ Equation of a circle is (x-x0)^2+(y-y0)^2=r^2. Solve for y (only the positive half) and just plot the points x,y for every x between x0-r and x0+r. I'm not exactly sure if it moves at a regular speed (I'll ask at /MA) but it certainly moves in a circle. Trig is definitely a more conventional method but I wasnt sure if "Turing" actually has any math libraries seeing as how it's a theoretical language >_> --ffroth 23:34, 30 October 2007 (UTC)

Yes, clearly what you intended to write (but failed) would have moved the wiper along a circular arc - but not at uniform rotational speed. Since the speed of progression along the X axis is uniform, the angular velocity will be spectacularly fast at the two ends of the travel and would slow down to a snails pace in the middle - in exactly the way that windscreen wipers don't! Worse still, you said:

 for x from 0 to 15
   draw line from 10,10 to x,Sqrt(10^2 - x^2)

When x is 11 (it's running from 0 to 15 - right?), you'll be calculating Sqrt(10^2 - 11^2) which is Sqrt(-21)...I'm going to go out on a limb and boldly claim that the Turing language is not going to be happy with you for that and consequently your program will be a small smoking ruin about two thirds of the way through!

Furthermore, even if it didn't screw up because of that, you'd have had a wiper that at one end was drawn from (10,10) to (0,10) and at the other end is drawn from (10,10) to (15,10) - so it's 10 units long at the start and only 5 long at the end - it's not staying the same length even if it didn't crash and burn for those other reasons. When you added your second 'wiper' made matters even worse by saying:

   draw line from 40,10 to x,Sqrt(10^2 - (x-40)^2)

So the Y coordinate runs from Sqrt(10^2 - (-40)^2) which is Sqrt(-1500)...Oh-oh! And runs up to Sqrt(10^2 - (-25)^2)...yep another square root of a negative number - this time, your program is a smoking ruin on the very first iteration - which removes some of the anticipation of the earlier version! Your excuse that you hadn't used trig because you had not yet ascertained whether Turing supports trig functions doesn't really fly because you were using Sqrt() - and you hadn't checked for that either. It would have been nice if you'd checked whether '^' means "to the power of" and not "exclusive or" as it does in most modern languages - because that would certainly tend to confuse our OP also!

It's hard to imagine code that could be more wrong! Sorry to comprehensively shred your reply - but perhaps it would have been better to check what you wrote before you challenged my statement that it was wrong. It's probably unwise for novice programmers to answer programming questions anyway.

SteveBaker 04:50, 31 October 2007 (UTC)

Oh come on, I was somewhat close. You're right of course about it not travelling at a constant speed (as the good folks at WP:RD/MA confirmed). Heres the code again with the changes in bold (I think it's right this time, but this is such a stupid way to do it, if Turing has trig support USE IT)

for x from 0 to 20
draw line from 10,10 to x,10-Sqrt(10^2 - (x-10)^2)
draw line from 40,10 to x+30,10-Sqrt(10^2 - (x-10)^2)
end

In my defense, I had just finished an epic 3-page homework problem dealing with that type of square root, and I was terribly mixed up with writing mathematical formulae and actually drawing them programmatically- especially I totally forgot we were in the 3rd quadrant. Oh and about the square root, I thought it would be a lot more likely that Turing has exponential support than trig support, and if it doesn't it's very easy to just calculate it without native support --ffroth 22:28, 31 October 2007 (UTC)

Oh and no, my current question at the math desk isn't that epic problem --ffroth 18:02, 1 November 2007 (UTC)

Servers

why is the lease duration in DHCP server is 8 days while it is in WINS server 6 days ? --87.109.25.36 22:37, 29 October 2007 (UTC)

"8 days" is not a rule. Most small office/home routers that act as DHCP servers have a setting that allows you to change this time. "6 days" is a common setting for offices with a 5-day work week, because it ensures that devices that were started on one Monday morning get a new lease every week, when they are started up on the next Monday. "8 days" is the opposite choice: it allows a computer shut down over a weekend to retain the same settings when it is started up on Monday. Some LAN administrators choose 30 hours; others choose 30 days. I've seen 61 minutes, but that LAN admin had some issues.... -SandyJax 20:35, 30 October 2007 (UTC)

Recording

I think I remember the mentioning of a video recording program on this page, capable of recording any video being played on a screen. Take a youtube video for instance. Load it, draw a box around it, then play and record it. Hit stop and you have a video in a half normal format (contrast to my previous problems). Can anyone remember its name?martianlostinspace ^{email me} 23:03, 29 October 2007 (UTC)

Gack! What a horrible solution. Just download the flv and convert it with mencoder. Your idea (or whoever made it if it's actually a program) is akin to putting a microphone up to a speaker and expecting a good quality recording. Besides, video playback is done by the graphics card (though not in the case of flash-based playback) --ffroth 23:15, 29 October 2007 (UTC)

OK then, maybe not as straight forward as I intended! Youtube is only an example. Videos in general. Although, your scenario of the mic and speaker is more akin to putting a camera straight in front of a screen, rather than the "virtual camera" I mention above. As for quality degradation, suppose this is going from DVD quality to an ipod. Perhaps I ought to have mentioned this. Would the degradation be so bad you couldn't really make anything out of it?martianlostinspace ^{email me} 23:47, 29 October 2007 (UTC)

"Screen video capturing device"?martianlostinspace ^{email me} 00:02, 30 October 2007 (UTC)

A Google search for "screen recorder" gives some examples. See also here, here and here. I've had perfectly adequate results with the free version of Bulent's Screen Recorder. --Richardrj ^{talk email} 06:23, 30 October 2007 (UTC)