Question

I would like to link 5 point (A,B,C,D,E) with line.

It is easy to make it with For Loop but there will be repeat linkage (A-B = B-A).

Any one have idea to prevent it happen?

Answer 1

Use itertools.combinations:

import itertools as it
points = ('A', 'B', 'C', 'D', 'E')
for pt1, pt2 in it.combinations(points, 2):
    print '{0}-{1}'.format(pt1, pt2)

prints

A-B
A-C
A-D
A-E
B-C
B-D
B-E
C-D
C-E
D-E