On 16 Mar 2005 06:49:09 -0800, rumours say that [EMAIL PROTECTED] might have written:
>Suppose I have a list of n floats x and a list of n floats w and I want >to compute x[0]*w[0] + .. + x[n-1]*w[n-1]. > >Is there some elegant expression (perhaps using lambda) to have it done >in one statement ? As in : > y = lambda x,w : ... > >I ask because the way I am doing it now : > y = 0 > for i in range(0,n): y += x[i]*w[i] > >doesn't seem very pythonic :) Your method seems to be the one closest to what's generally considered as pythonic. Anyway, a functional equivalent: .>> from itertools import starmap, izip .>> import operator .>> x= [1,2,3,4] .>> w=[3.0, 6.0, 9.0, 12.0] .>> sum(starmap(operator.mul, izip(x,w))) 90.0 .>> -- TZOTZIOY, I speak England very best. "Be strict when sending and tolerant when receiving." (from RFC1958) I really should keep that in mind when talking with people, actually... -- http://mail.python.org/mailman/listinfo/python-list
