dual -- dual module or map

Ways to use dual :

• dual(BettiTally) -- see BettiTally -- the class of all Betti tallies
• dual(ChainComplex) -- dual
• dual(ChainComplexMap) -- dual of a chain complex
• dual(CoherentSheaf) -- dual coherent sheaf
• dual(Matrix) -- dual of a map
• dual(Module) -- dual module
• dual(MonomialIdeal) -- the Alexander dual of a monomial ideal
• dual(MonomialIdeal,List) -- the Alexander dual
• dual(MonomialIdeal,RingElement) -- the Alexander dual
• dual(SheafMap) (missing documentation)

For the programmer

The object dual is a method function with options.