minpres

Usage:
    <minpres j varlist j' f
Find a minimal presentation k[varlist]/j' for a given ring R/j,
and a map f: R --> k[varlist] inducing an isomorphism
   R/j ----> k[varlist]/j'
Parameters:
            j = ideal, possibly containing some minimal forms
            varlist = a variable list suitable for the ring command
Output values:
            j' = an ideal in k[varlist]
            f  = an ideal of linear forms and zeros in k[varlist],
                    representing the projection map from R.
k[varlist] is of course isomorphic, via f, to R/j1, where
j1 is the ideal generated by the linear forms in j.
Caveats:
    If not enough variables are given, the script puts in A[1]...A[100]