gkz

[ A b] gkz [eq v]
[ A  ] gkz [eq v]
[    ] gkz [eq v]
array of array of integer A; array of integer b;
eq is the GKZ system defined by the matrix A and the parameter b.
v is the list of variables.
Default values of A and b are in gkz.A and gkz.b
For details, see Functional analysis and its applications, 23, 1989, 94--106.
    Grobner deformations of hypergeometric differential equations, Springer, 1999
Example 1: [ [[1 1 1 1] [0 1 3 4]] [1 2]] gkz rrank :: 
Example 2: [ [[1 1 1 1] [0 1 3 4]] [0 0]] gkz rrank ::