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Macaulay2Doc :: codim(QuotientRing)

codim(QuotientRing) -- compute the codimension

Synopsis

Description

Computes the codimension of the presentation ideal of R over its ambient polynomial ring.
i1 : R = QQ[x,y]/(ideal(x,y) * ideal(x-1))

o1 = R

o1 : QuotientRing
i2 : codim R

o2 = 1
However, the following may not be the expected result.
i3 : R = QQ[x,y]/(ideal(x,y) * ideal(x-1))

o3 = R

o3 : QuotientRing
i4 : codim R

o4 = 1
i5 : codim (R/x)

o5 = 2

See also