dual Module -- dual module

dual Module -- dual module

Synopsis:

Function: dual -- dual module or map

Input:

an instance of class Module.

Output:

an instance of class Module.

dual M -- the dual of a module.

Code:

     -- ../../../Macaulay2/m2/modules2.m2:449-453
     dual Module := Module => F -> if F.?dual then F.dual else F.dual = (
          if not isFreeModule F then kernel transpose presentation F
          else (
               sendgg (ggPush F, ggtranspose); 
               new Module from ring F))