On Thu, May 26, 2011 at 21:52, santhu kumar <mesanthu@gmail.com> wrote:

Hello All,

I am trying to extend a piece of matlab code into numpy.

And I am stuck at converting, ( x is a nX3 matrix) Matlab : dim = size(x,1) % would be n nx = x(:,:,ones(1,dim)) % would be nX3Xn matrix ..

Now the same in Numpy seems to be tricky to me .. Can somebody help me in writing this piece of code.

[~] |1> n = 10 [~] |2> x = np.arange(n*3).reshape((n,3)) [~] |3> nx = x[:,:,np.newaxis][:,:,np.zeros(n, dtype=int)] [~] |4> nx.shape (10, 3, 10) [~] |5> nx array([[[ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1], [ 2, 2, 2, 2, 2, 2, 2, 2, 2, 2]], [[ 3, 3, 3, 3, 3, 3, 3, 3, 3, 3], [ 4, 4, 4, 4, 4, 4, 4, 4, 4, 4], [ 5, 5, 5, 5, 5, 5, 5, 5, 5, 5]], [[ 6, 6, 6, 6, 6, 6, 6, 6, 6, 6], [ 7, 7, 7, 7, 7, 7, 7, 7, 7, 7], [ 8, 8, 8, 8, 8, 8, 8, 8, 8, 8]], [[ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9], [10, 10, 10, 10, 10, 10, 10, 10, 10, 10], [11, 11, 11, 11, 11, 11, 11, 11, 11, 11]], [[12, 12, 12, 12, 12, 12, 12, 12, 12, 12], [13, 13, 13, 13, 13, 13, 13, 13, 13, 13], [14, 14, 14, 14, 14, 14, 14, 14, 14, 14]], [[15, 15, 15, 15, 15, 15, 15, 15, 15, 15], [16, 16, 16, 16, 16, 16, 16, 16, 16, 16], [17, 17, 17, 17, 17, 17, 17, 17, 17, 17]], [[18, 18, 18, 18, 18, 18, 18, 18, 18, 18], [19, 19, 19, 19, 19, 19, 19, 19, 19, 19], [20, 20, 20, 20, 20, 20, 20, 20, 20, 20]], [[21, 21, 21, 21, 21, 21, 21, 21, 21, 21], [22, 22, 22, 22, 22, 22, 22, 22, 22, 22], [23, 23, 23, 23, 23, 23, 23, 23, 23, 23]], [[24, 24, 24, 24, 24, 24, 24, 24, 24, 24], [25, 25, 25, 25, 25, 25, 25, 25, 25, 25], [26, 26, 26, 26, 26, 26, 26, 26, 26, 26]], [[27, 27, 27, 27, 27, 27, 27, 27, 27, 27], [28, 28, 28, 28, 28, 28, 28, 28, 28, 28], [29, 29, 29, 29, 29, 29, 29, 29, 29, 29]]]) -- Robert Kern "I have come to believe that the whole world is an enigma, a harmless enigma that is made terrible by our own mad attempt to interpret it as though it had an underlying truth."   -- Umberto Eco