Singular

7.10.6.30 ncrepGetRegularZeroMinimal

Usage:

ncrep q = ncrepGetRegularZeroMinimal(f, vars);

Return:

q is a representation of f with
minimal dimension

Assumption:

f is regular at zero, i.e.,
f(0) has to be defined

Note:

list vars = list(x1, ..., xn) has to consist
exactly of the nc variables occuring in f

LIB "ncrat.lib";
ncInit(list("x", "y"));
ncrat f = ncratFromString("inv(1+x*y-y*x)");
list vars = list(x, y);
ncrep q = ncrepGetRegularZeroMinimal(f, vars);
q;
==> lvec=
==> 0,1,0
==> 
==> mat=
==> 1, y, 0, 
==> -x,1, -y,
==> 0, -x,1  
==> 
==> rvec=
==> 0, 
==> -1,
==> 0  
==>