GradedModule -- the class of all graded modules
A new graded module can be made with 'M = new GradedModule'. The i-th module can be installed with a statement like M#i=N, and can be retrieved with an expression like M_i. The ground ring should be installed with a statement like M.ring = R.
Types of graded module :
Functions and methods returning a graded module :
Methods that use a graded module :