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NormalToricVarieties :: toricDivisor

toricDivisor -- make a torus-invariant Weil divisor

Synopsis

Description

Given a list of integers and a normal toric variety, this method returns the torus-invariant Weil divisor such the coefficient of the i-th torus-invariant prime divisor is the i-th entry in the list. The indexing of the torus-invariant prime divisors is inherited from the indexing of the rays in the associated fan. In this package, the rays are ordered and indexed by the nonnegative integers.
i1 : PP2 = projectiveSpace 2;
i2 : D = toricDivisor({2,-7,3},PP2)

o2 = 2*D  - 7*D  + 3*D
        0      1      2

o2 : ToricDivisor on PP2
i3 : D === 2* PP2_0 - 7*PP2_1 + 3*PP2_2

o3 = true
i4 : vector D

o4 = | 2  |
     | -7 |
     | 3  |

       3
o4 : ZZ
Although this is a general method for making a torus-invariant Weil divisor, it is typically more convenient to simple enter the appropriate linear combination of torus-invariant Weil divisors.

See also

Ways to use toricDivisor :