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Divisor :: reflexifyModuleWithMap

reflexifyModuleWithMap -- Compute the canonical map from a module to its double-dual

Synopsis

Usage:
M2 = reflexifyModuleWithMap( M1 )
Inputs:
- M1, a module
Outputs:
- M2, a module

Description

Get the double-dual (S2 - identification) M1^** of a module M1 and return the canonical map M1 -> M1^**

i1 : R = QQ[x,y]

o1 = R

o1 : PolynomialRing

i2 : m = ideal(x,y)

o2 = ideal (x, y)

o2 : Ideal of R

i3 : M = m*R^1

o3 = image | x y |

                             1
o3 : R-module, submodule of R

i4 : f = reflexifyModuleWithMap( M )

o4 = | x y |

o4 : Matrix

i5 : source f

o5 = image | x y |

                             1
o5 : R-module, submodule of R

i6 : target f

      1
o6 = R

o6 : R-module, free

See also

reflexifyIdeal -- Calculate the double dual of an ideal
reflexifyModule -- Calculate the double dual of a module
isReflexive -- Checks whether an ideal or module is reflexive

Ways to use `reflexifyModuleWithMap` :

reflexifyModuleWithMap(Module)