Fri, 10 Sep 2010 14:35:46 +0200, Radek Machulka wrote: > Thanks, but... > >>>> x = array([[0,0,0,0],[0,1,0,0],[0,0,1,1],[0,0,0,0]]) x > array([[0, 0, 0, 0], > [0, 1, 0, 0], > [0, 0, 1, 1], > [0, 0, 0, 0]]) >>>> i, j = x.any(0).nonzero()[0], x.any(1).nonzero()[0] Should be >>> j, i = x.any(0).nonzero()[0], x.any(1).nonzero()[0]