Dynamic or not?

[rishiyoor at gmail.com]

I'm trying to write a program that will find the distance between two
groups of points in space, which have cartesian co-ordinates X,Y and
Z.

I need to find the distances between each point in one group and every
point in the other group. So if group 1 has 6 points and group 2 had 8
points, I will calculate 6 x 8 = 48 distances. But I do not know the
number of points the user will want to use. It is typically between 50
and 500 in both groups combined, but may be more. Since the memory
required for the distances will be much larger than the points
themselves, I am wondering if I will have to allocate memory
dynamically or if there are easier ways of solving such problems in
Python.

Suggestions for amateur programmer will be appreciated.