|  |  D.2.9.7 pnormalform Procedure from libraryredcgs.lib(see  redcgs_lib).
 
Example:Usage:
pnormalform(f,N,W);
f: the polynomial to be reduced modulo N,W (in parameters and
variables)
 N: the null conditions ideal
 W: the non-null conditions (set of irreducible polynomials, ideal)
 
Return:
a reduced polynomial g of f, whose coefficients are reduced
modulo N and having no factor in W.
Note:
Should be called from ring @R. Ideals N and W must be polynomials
in the parameters forming a red-specification (see definition) the papers).
 |  | LIB "redcgs.lib";
ring R=(0,a,b,c),(x,y),dp;
setglobalrings();
poly f=(b^2-1)*x^3*y+(c^2-1)*x*y^2+(c^2*b-b)*x+(a-bc)*y;
ideal N=(ab-c)*(a-b),(a-bc)*(a-b);
ideal W=a^2-b^2,bc;
def r=redspec(N,W);
pnormalform(f,r[1],r[2]);
==> xy2+(b)*x
 | 
 
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