Optimising list comparison

[Kragen Sitaker]

Graham Ashton <graz at mindless.com> writes:
> A friend of mine is using Python in a research project where he needs to
> compare each element of two vectors, such that comparing [a, b, c] and 
> [d, e, f] would involve comparing a with d, b with e and c with f.

Numeric.alltrue(Numeric.logical_or(a == b, Numeric.logical_or(a == -1,
                                                              b == -1)))

It might not be faster than psyco, but it will be faster than looping
in interpreted Python over all the elements of each vector if the
vectors are relatively large.