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Divisor :: reflexifyModule

reflexifyModule -- Calculate the double dual of a module

Synopsis

Description

Get the double-dual (S2 - identification) of a module
i1 : R = QQ[x,y,z]/ideal(x^2-y*z)

o1 = R

o1 : QuotientRing
i2 : m = ideal(x,y,z)

o2 = ideal (x, y, z)

o2 : Ideal of R
i3 : prune reflexifyModule(m*R^2)

      2
o3 = R

o3 : R-module, free
i4 : I = ideal(x,y)

o4 = ideal (x, y)

o4 : Ideal of R
i5 : prune reflexifyModule(I*R^1)

o5 = cokernel {1} | x  -y |
              {1} | -z x  |

                            2
o5 : R-module, quotient of R
i6 : prune reflexifyModule(I^2*R^1)

      1
o6 = R

o6 : R-module, free, degrees {1}

See also

Ways to use reflexifyModule :