The support of a torus-invariant Weil divisor is the set of torus-invariant prime divisors which appear with nonzero coefficients in the unique expression for this divisor. In this package, we encode this information by indexing the torus-invariant prime divisors with appear with a nonzero coefficient. The indexing of the torus-invariant prime divisors is inherited from the indexing of the rays in the associated fan.
i1 : PP2 = projectiveSpace 2;
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i2 : D = 2*PP2_0 - 7*PP2_1 + 3*PP2_2
o2 = 2*D - 7*D + 3*D
0 1 2
o2 : ToricDivisor on PP2
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i3 : support D
o3 = {0, 1, 2}
o3 : List
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i4 : E = PP2_0-5*PP2_2
o4 = D - 5*D
0 2
o4 : ToricDivisor on PP2
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i5 : support E
o5 = {0, 2}
o5 : List
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i6 : support (6*PP2_1)
o6 = {1}
o6 : List
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