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7.7.13.0. facSubWeyl
Procedure from library ncfactor.lib (see ncfactor_lib).

Usage:
facSubWeyl(h,x,y); h, X, D polynomials

Return:
list

Assume:
X and D are variables of a basering, which satisfy DX = XD +1.
That is, they generate the copy of the first Weyl algebra in a basering.
Moreover, h is a polynomial in X and D only.

Purpose:
compute factorizations of the polynomial, which depends on X and D.

Example:
 
LIB "ncfactor.lib";
ring r = 0,(x,y,z),dp;
matrix D[3][3]; D[1,3]=-1;
def R = nc_algebra(1,D); // x,z generate Weyl subalgebra
setring R;
poly h = (x^2*z^2+x)*x;
list fact1 = facSubWeyl(h,x,z);
// compare with facFirstWeyl:
ring s = 0,(z,x),dp;
def S = nc_algebra(1,1); setring S;
poly h = (x^2*z^2+x)*x;
list fact2 = facFirstWeyl(h);
map F = R,x,0,z;
list fact1 = F(fact1); // it is identical to list fact2
testNCfac(fact1); // check the correctness again
==> 1
See also: facFirstShift; facFirstWeyl; testNCfac.