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D.6.7.2 gmsnf

Procedure from library gmssing.lib (see gmssing_lib).

Usage:
gmsnf(p,K); poly p, int K

Assume:
basering returned by gmsring

Return:
list nf;
ideal nf[1]; projection of p to <gmsbasis>C[[s]] mod s^(K+1) ideal nf[2]; p==nf[1]+nf[2]

Note:
computation can be continued by setting p=nf[2]

Example:
 
LIB "gmssing.lib";
ring R=0,(x,y),ds;
poly t=x5+x2y2+y5;
def G=gmsring(t,"s");
setring(G);
list l0=gmsnf(gmspoly,0);
print(l0[1]);
==> -1/2y5
list l1=gmsnf(gmspoly,1);
print(l1[1]);
==> -1/2y5+1/2s
list l=gmsnf(l0[2],1);
print(l[1]);
==> 1/2s