Hi Bernard, You can do this with Numeric (http://numeric.scipy.org/)
import Numeric aList = [ [1,1,1], [2,2,2,], [3,3,3] ] bList = Numeric.array(aList, "i") print bList[:,0] displays-> [1 2 3] you can convert the array back to a list if you want like this: bList.tolist() so... result = Numeric.array(aList, "i")[:,0].tolist() should do what you want in one line. Fred > aList = [ [1,1,1], [2,2,2,], [3,3,3] ] > aList[:][0] = 10 > > > If I print aList[:], I get the list with the nested sublists. > > >>> aList[:] > [[1, 1, 1], [2, 2, 2], [3, 3, 3]] > > > But as soon as I introduce the [0], in an attempt to access the first > element of each sublist, I get the first sublist in its entirety: > > >>> aList[:][0] > [1, 1, 1] > > > I would have hoped to get something like > [1, 2, 3] > > > Is this possible at all? > > Thanks > Bernard > _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor