I Am searching the Web now for 3 weeks ( including SO) i dont find someone who has already asked or solved it.
I need a Permutation of an Array in PHP of only uniq ordered values.
$array = array('Number1', 'Number2', 'Number3', 'Number4', 'Number5', 'Number6');
usually a permutation will be like
.1 Number1, Number2, Number3, ...; .2 Number1, Number2, Number4, ...; .3 Number2, Number4, Number1, ...;
But i need it ordered and uniq. so the 3rd line would be ordered to
.1 Number1, Number2, Number3, ...; .2 Number1, Number2, Number4, ...; .3 Number1, Number2, Number4, ...;
And that means Row 3 is NOT uniq and will not be saved in a new array.
2nd Example
array('A','B','C') A AB AC ABC ACB B BC BA BCA BAC C CA CB CAB CBA
I need the output like this
A B C AB BC AC ABC
I kinda solved it so far. BUT my solution is like stoneage and just sorts all new array_permutations and array_filter them. thats like 100 Years calculation time cause 6 numbers permutated with all possabilitys is like X^10 -.-
Please help me guys.
btw: its my first post here, so be gentle :D
I strongly advise you to take a look the python module called itertools.
It's a module for efficient looping and constains numerous operations involving permutations, combinatorics and more.
Despite being a module written in python language it shouldn't difficult to port the code to PHP language. However, since several of these operations may require considerable memory usage is a good idea to use PHP 5.5+, because in this version generators were included.