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From the news page:
I only had one number theory class as an undergrad and we didn't talk about Mock Theta functions, but some researchers at UW apparently have made some major breakthroughs in Mock Theta function theory:
http://www.news.wisc.edu/13497.html[^]
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Marcus Kwok
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Hello everyone,
I am in search of an algorithm to find the most appropriate division technique of an area.
For example; I have 3 100x500 cm of sheets and I want to get 15 50x40 cm, 2 100x100 etc. sheets. So I have to divide these 100x500 cm sheets into smaller parts. But when I -let's say- try to get 15 50x40 cm sheets from only one 100x500 cm sheet probably there will be a loss (500 mod 40 != 0).
So I have to use a combine of 50x40, 100x100 etc. sheets.
Also there isn't a must to only use quadrangles. Polygonial sheets may also used.
So is there an algorithm to get the desired number of different area shapes from a number of main shapes with less loss ?
Thanks for your helps and best regards.
.:: Something is Wrong ::.
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IIRC what you're describing is an NP complete problem.
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Rules of thumb should not be taken for the whole hand.
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Sorry about my English I am not good with abbreviations. So what do you mean by IIRC and NP..
.:: Something is Wrong ::.
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Maximilien wrote: NP stands for a Non Polygonial class of problems.
I think you mean "nondeterministic polynomial".
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Marcus Kwok
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sorry. IIRC is short for If I Recall Correctly, and is internet slang for I think this is right, but am not certain.
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Rules of thumb should not be taken for the whole hand.
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But at least there must be a subset of the NP, that is deterministic.. Am I wrong ?
.:: Something is Wrong ::.
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There is, it's the set of problems called P. That's the sort of problem that can be done in at worst polynomial time on a normal computer.
Your question appears to indicate a bit of a vocabulary/jargon problem.
P is the set of problems that can be done in polynomial time on a dterministic turing machine. All normal computers are deterministic turing machines.
NP is the set of problems that can be done in polynomial time on a nondterministic turing machine. A nondeterministic machine guesses the correct solution (the first time, every time, in a nonexplainable way) and then proves that it is correct. A deterministic turing machine can simulate a non deterministic one, by trying each possible solution in sequence. This takes exponential time. A quantum computer is capable of directly running multiple data sets at once, but the fastest QC ever built is still no faster than a normal machine due to the low maximum qbit count it can work with.
It's believed, but not proven than P is a subset of NP, but that the two are not equal.
Depending on the problem, and conditions applied to it, there may or may not be a solution in P that can give a reasonable approximation with a known worst case error. Except for well known problems the approximations are unlikely to be published anywhere except in academic journals.
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Rules of thumb should not be taken for the whole hand.
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Really thanks for the explanation. So if we return to the point is there a way to "guess" or "approximate" the most proper division technique ?
.:: Something is Wrong ::.
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probably, but given the lack of response I don't think anyone posting here is aware of one. If you can't find anything via google you'll need to do a journal search for papers on the subject. I don't know if CS journals charge for online access or not. If so, it may be cheaper to visit the library of a major college/university than to buy access.
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Rules of thumb should not be taken for the whole hand.
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Ok, I will give a try, and if get a result I will share it . But at least, which keywords should I use in search? Any ideas?
.:: Something is Wrong ::.
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Yep. Following the link from there to the knapsack problem confirmed my vague recollection that it was NP-Complete.
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Rules of thumb should not be taken for the whole hand.
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y=x-(xz)
what is the formula for finding the value of x from the given formula above.
Thanks
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x = y / (1 - z)
"Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning." - Rick Cook www.troschuetz.de
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for z!=1
"Throughout human history, we have been dependent on machines to survive. Fate, it seems, is not without a sense of irony. " - Morpheus
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Can any one tell me which is the best book of Advance Algoritham analysis
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We used Introduction to Algorithms[^] (called "CLR" or "CLRS" for short) in my algorithms class, and it was a pretty good book.
TAOCP[^] is also supposed to be very highly regarded, but I have not personally ventured into that territory yet
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Marcus Kwok
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Mythbusters had a recent episode on this problem. They used huge and thin. Didn't hurt to have a forklift to help horse it around after it got thick.
The evolution of the human genome is too important to be left to chance idiots like CSS.
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The user provides the start, end and control points for a bezier curve on a bitmap. I need to look a certain amount above and below each point on the curve based on an int X location and rounded Y location. Is there a formula anyone knows of which will calculate the Y value of a bezier curve given the X value and the four points?
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Hi,
I dont think it is easy to find y from x, given that x(t) and y(t) are both polynomials.
But maybe you could modify y(t) by adding your fixed vertical distance, and then walk
the modified bezier.
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