n-dimensional simplex quadrature

This script computes the weights and nodes for a Gauss quadrature rule on an n-dimensional simplex. The user can either specify the vertices of the simplex or only the dimension and the vertices of the unit simplex will then be used.

The first four simplexes are

n | Domain
--|------------
1 | Interval
2 | Triangle
3 | Tetrahedron
4 | Pentatope

Thanks to John D'Errico for helping with this script.