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Complexes :: Working with Ext

Working with Ext -- information about functorial properties

Hom and Ext

  • Ext^ZZ(Module,Module) -- Ext module
  • (Ext, ZZ, Matrix, Matrix) (missing documentation)
  • (Ext, ZZ, Matrix, Module) (missing documentation)
  • (Ext, ZZ, Module, Matrix) (missing documentation)
  • Hom(Complex,Complex) -- the complex of homomorphisms between two complexes
  • Hom(ComplexMap,ComplexMap) -- the map of complexes between Hom complexes
  • homomorphism(ComplexMap) (missing documentation)
  • homomorphism'(ComplexMap) (missing documentation)

Yoneda extensions and elements of Ext

  • yonedaMap(Matrix) -- creates a chain complex map representing an extension of modules
  • yonedaMap'(ComplexMap) (missing documentation)
  • yonedaExtension(Matrix) -- creates a chain complex representing an extension of modules
  • yonedaExtension'(Complex) -- identifies the element of Ext corresponding to an extension
  • yonedaProduct(Matrix,Matrix) (missing documentation)
  • yonedaProduct(Module,Module) (missing documentation)

See also