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Ring / Ideal -- make a quotient ring

Synopsis

Description

If I is a ring element of R or ZZ, or a list or sequence of such elements, then I is understood to be the ideal generated by these elements. If I is a module, then it must be a submodule of a free module of rank 1.
i1 : ZZ[x]/367236427846278621

           ZZ [x]
o1 = ------------------
     367236427846278621

o1 : QuotientRing
i2 : A = QQ[u,v];
i3 : I = ideal random(A^1, A^{-2,-2,-2})

            5        2    8       2  2    2  2   9  2
o3 = ideal (-*u*v + v , - -*u*v - -*v , - -*u  - -*v )
            2             9       5       3      5

o3 : Ideal of A
i4 : B = A/I;
i5 : use A;
i6 : C = A/(u^2-v^2,u*v);
i7 : D = GF(9,Variable=>a)[x,y]/(y^2 - x*(x-1)*(x-a))

o7 = D

o7 : QuotientRing
i8 : ambient D

o8 = (GF 9)[x, y]

o8 : PolynomialRing
The names of the variables are assigned values in the new quotient ring (by automatically running use R) when the new ring is assigned to a global variable.

Warning: quotient rings are bulky objects, because they contain a Groebner basis for their ideals, so only quotients of ZZ are remembered forever. Typically the ring created by R/I will be a brand new ring, and its elements will be incompatible with the elements of previously created quotient rings for the same ideal.

i9 : ZZ/2 === ZZ/(4,6)

o9 = true
i10 : R = ZZ/101[t]

o10 = R

o10 : PolynomialRing
i11 : R/t === R/t

o11 = false