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PolyRingHom

homomorphism of polynomial rings

Syntax 
PolyRingHom(R: RING, S: RING, CoeffHom: RINGHOM, images: LIST): RINGHOM

Description
This function create the homomorphism of (polynomial) algebras between R and S. This is uniquely defined by the images of the indeterminated of R and the homomorphism CoeffRing(R) into S.

Example 
/**/ R ::= QQ[x,y];
/**/ S ::= QQ[a,b,c];
/**/ SmodJ := NewQuotientRing(S, ideal(RingElem(S,"a")^2-1));

/**/ Use SmodJ;
/**/ phi := PolyRingHom(R, SmodJ, CanonicalHom(QQ,SmodJ), [a,b]);
/**/ Use R;
/**/ phi(x);
(a)

See Also