TG wrote: > Hi there. > > I want to do some intensive computations with numpy, and I'm > struggling a bit to find myyyyy wayyyyyy.
The best place to ask numpy questions is on the numpy mailing list. http://www.scipy.org/Mailing_Lists > Here is the problem : > > m and d are two matrices : > >> m.shape = (x,y,a,b) >> d.shape = (a,b) > > I want to return >> i.shape = (x,y) > with >> i[x,y] = sum(m[x,y] * d) > > I already found that >> m[:,:] * d > will give me a matrix of shape (x,y,a,b) containing the products. > > Now I want to sum up on axis 2 and 3. If I do : >> (m[:,:] * d).sum(axis=3).sum(axis=2) > it seems like I get my result. > > I'm wondering : is this syntax leading to efficient computation, or is > there something better ? That's about it. There's no need for the [:,:], though. -- 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 -- http://mail.python.org/mailman/listinfo/python-list
