> There must be a better way to multiply the elements of one list by > another: > > a = [1,2,3] > b = [1,2,3] > c = [] > for i in range(len(a)): > c.append(a[i]*b[i]) > a = c > print a > [1, 4, 9] > > Perhaps a list comprehension or is this better addressed by NumPy?
First of all: it's considered bad style to use range if all you want is a enumeration of indices, as it will actually create a list of the size you specified. Use xrange in such cases. You can use a listcomp like this: c = [a[i] * b[i] for i in xrange(len(a))] But maybe nicer is zip: c = [av * bv for av, bv in zip(a, b)] And if lists get large and perhaps multidemnsional, numpy certainly is the way to go. Diez -- http://mail.python.org/mailman/listinfo/python-list
