Rform 'file1' ['file2'] [-e=epsilon]
file1: bravais_TYP of the finite unimodular group G.
file2: (OPTIONAL) matrix_TYP of a single matrix A. If file2 is not given, A=In the
identity matrix is assumed.
The program calculates the sum of gtrAg with g in G in a seminumerical
way, and divides the results by the greatest common divisor of it's
Note that this gives a way to construct a positive definite, G-invariant
-e=epsilon : epsilon is a control parameter, controlling the accuracy
of the convergence. It is given as an integer epsilon >= 100, and
bigger value stand for a more accurate convergence.
See also for Invar_space.