>Psychtoolbox>PsychOneliners

find repeated rows or columns in a matrix.
inds = FindRepeatAlongDims(in,dim)
example:
in =
1 2 3
2 3 4
4 5 6
1 2 3
1 2 3
4 5 6
FindRepeatAlongDims(in,1) % check for repeated rows
ans =
5 % the fifth row is the same as the fourth row,
repeat!

for N-D dimensions, this function can also find repeats along the highest
dimension, such as finding repeated planes in a 3D matrix.