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Divisor :: moduleWithSectionToDivisor

moduleWithSectionToDivisor -- Compute the effective divisor associated to the section of a module

Synopsis

Description

Given map from a rank 1 free module to a rank 1 reflexive module M, this finds the unique divisor D corresponding to the section. In the example below, we consider the divisor corresponding to the inclusion x*R1 -> (x,y)*R1
i1 : R = QQ[x,y,z]/ideal(x^2-y*z)

o1 = R

o1 : QuotientRing
i2 : M = (ideal(x,y))*R^1

o2 = image | x y |

                             1
o2 : R-module, submodule of R
i3 : mat = map(M, R^1, {{1},{0}})

o3 = {1} | 1 |
     {1} | 0 |

o3 : Matrix
i4 : moduleToDivisor(M)

o4 = -1*Div(y, x) of R

o4 : WDiv

See also

Ways to use moduleWithSectionToDivisor :