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ManuelM
10-19-2010, 04:38 AM
Does anyone have a melScript that breaks down a number into it's factors as described here: http://en.wikipedia.org/wiki/Factorization
(I'm aware you can do it with python)

thanks,
m.

mduvekot
10-19-2010, 03:05 PM
http://www.thnkr.com/wiki/index.php?title=Factorize

ManuelM
10-20-2010, 12:19 AM
thanks a lot!

do you mind to explain this line:
($n/$p) % 1)

I never came accross this syntax in a mel script and couldn't find any hints in maya's help.
thanks,
m

mduvekot
10-20-2010, 01:17 AM
do you mind to explain this line:
($n/$p) % 1)



% means Modulo. It's the remainder of the integer division by 1. What I'm saying in if (!(($n/$p) % 1)) is if the remainder of the integer division of $n by $p is not something, (IOW, it;'s zero)

ManuelM
10-20-2010, 03:57 AM
Ok, so I guess this is how I would use modulo?


global proc float mod(float $i, float $k)
{
return $mod = (($i/$k) %1);
}
if (`mod 9 4` == 0){print "remainder = 0\n";} else {print "remainder != 0\n";
}

if (`mod 9 3` == 0){print "remainder = 0\n";} else {print "remainder != 0\n";
}

uiron
10-20-2010, 10:51 AM
your proposed factorization has a problem, as result for 1025 should be [5,5,41]. here it is fixed, though i'd enhance it further to not have a hardcoded list of primes.


global proc int[] MDfactorize(int $number){
int $listOfPrimes[] = {2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,179,181,191,193,197,199,211,223,227,229,233,239,241,251,257,263,269,271,277,281,283,293,307,311,313,317,331,337,347,349,353,359,367,373,379,383,389,397,401,409,419,421,431,433,439,443,449,457,461,463,467,479,487,491,499,503,509,521,523,541,547,557,563,569,571,577,587,593,599,601,607,613,617,619,631,641,643,647,653,659,661,673,677,683,691,701,709,719,727,733,739,743,751,757,761,769,773,787,797,809,811,821,823,827,829,839,853,857,859,863,877,881,883,887,907,911,919,929,937,941,947,953,967,971,977,983,991,997};

int $result[];
int $prime;
for ($prime in $listOfPrimes) {
while ($number>0 && ($number % $prime)==0){
$result[size($result)] = $prime;
$number = $number/$prime;
}
}
return $result;
}

MDfactorize(1025);

mduvekot
10-20-2010, 02:52 PM
Agreed, that's much better.

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