Recipe 121574 revision 1

#!/usr/bin/env python

""" Matrix-vector multiplication """

def matmult(m, v):
    nrows = len(m)
    w = [None] * nrows
    for row in range(nrows):
        w[row] = reduce(lambda x,y: x+y, map(lambda x,y: x*y, m[row], v))
    return w
   

#................................................
if __name__=='__main__':
    m, n = 2, 3
    vec = range(1, n+1)
    mat = [map(lambda x: i*n+x+1, range(n)) for i in range(m)]
    print 'vec=', vec
    print 'mat=', mat
    print 'mat . vec=', matmult(mat, vec)

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• revision 1 (22 years ago)