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SegreClasses :: isMultiHom

isMultiHom -- Tests if an ideal is multi-homogeneous with respect to the grading of its ring

Synopsis

Description

Given an ideal in the coordinate R ring of ℙn1x...xℙnm this method tests if whether the input ideal is multi-homogeneous with respect to the grading on R.

i1 : R = makeProductRing({1,2})

o1 = R

o1 : PolynomialRing
i2 : x=gens R

o2 = {a, b, c, d, e}

o2 : List
i3 : degrees R

o3 = {{1, 0}, {1, 0}, {0, 1}, {0, 1}, {0, 1}}

o3 : List
i4 : isMultiHom ideal(x_0^2*x_2+x_1*x_2^2)
Input term below is not homogeneous with respect to the grading
 2       2
a c + b*c

o4 = false
i5 : isMultiHom ideal(x_0^2*x_2+x_1^2*x_3)

o5 = true

Ways to use isMultiHom :