testWalker -- tests Walker's formula

Synopsis

Usage:

t = testWalker M
Inputs:
- M, a module, of finite length
Outputs:
- t, a Boolean value,

Description

Verifies Walker's Theorem for a finite length graded module over a polynomial ring of char not 2: (2^(codim M)*length M + sum toList (excess M)) == (sum of the betti numbers of M)*(length M)

Caveat

Returns an error if any homology has infinite length

For the programmer

The object testWalker is a function closure.