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QuotientingHom

returns the projection homomorphism into a quotient ring

Syntax
QuotientingHom(P: RING): RINGHOM

Description
This function returns the projection homomorphism of a ring R into a quotient ring R/I .

It is equivalent to (indeed it is called by) CanonicalHom(BaseRing(RModI), RModI) .

Example
/**/ Use P ::= QQ[i];
/**/ f := i^3;
/**/ CC := P/ideal(i^2+1);
/**/ phi := QuotientingHom(CC);  -- phi: P -> CC
/**/ RingOf(phi(f));
/**/ phi(f)^2;
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See Also