Singular

D.15.23.10 invertAlgebraMorphism

Usage:

invertAlgebraMorphism(map p,int n), where p is an algebra morphism k[x1,...,xn]->k[y1,...,ym],
or invertAlgebraMorphism(ideal p,int n) if you represent the map as an ideal

Return:

the inverse of p mod (maxideal)^n.
If n=-1, try for infinite precision. If input was an ideal, return an ideal.

Note:

the algorithm used is described in [1], chapter 3.2

LIB "VecField.lib";
ring r = 0, (x, y, z),ds;
vector v = [-1,-1,-1];
VecField V = v;
V.precision = 4;
map phi = r, x-2y2+z3,2y+y3+z,z;
map phiinv = invertAlgebraMorphism(phi,4);