I have run across this issue a few times in the past. The following 8x4 array has several rows that are 'rotational duplicates'.
]n=.8 4$2 4 1 3 2 3 4 1 3 4 1 2 3 2 4 1 1 3 2 4 4 1 2 3 1 2 3 4 4 1 3 2 2 4 1 3 2 3 4 1 3 4 1 2 3 2 4 1 1 3 2 4 4 1 2 3 1 2 3 4 4 1 3 2 Is it possible to develop a verb that would find the rows that are rotational duplicates of each other. That is, find all the rows that would be the same, if each row was rotated some integer value in the first dimension. The output of the verb would be the same shape array, but with each duplicate row rotated such that they show as identical. Picking the 'standard' rotation for a set of rotational duplicates is up to the implementer. Skip ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
