- ls = [ lagrange_coefficient(k, x, xs) for k in range(0, len(xs)) ]
- sigma = sum([ ys[k] * ls[k] for k in range(0, len(xs)) ])
+ ls = [ lagrange_coefficient(k, x, xs) for k in xrange(len(xs)) ]
+ sigma = sum([ ys[k] * ls[k] for k in xrange(len(xs)) ])