The following two 4x4 arrays are rearrangements of each other's rows.
3 2 1 0
1 0 3 2
2 3 0 1
0 0 0 0
2 3 0 1
3 2 1 0
1 0 3 2
0 0 0 0
I would like to know a way to acknowledge two arrays as being rearrangements of
each other. Eventually my goal is to compare long lists of such arrays and nub
out duplicates - duplicates being rearrangements.
The only way I can think to do this is to cycle through all permutations of the
row of one of the arrays and test for equality with the other array, using A. .
Of course, there are 24 permutations to test for 4x4 arrays, but obviously for
bigger arrays things get worse.
Is there a faster way to check two arrays are (ignoring row permutations)
equivalent?
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