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Packages » Macaulay2Doc :: Ext^ZZ(Module,Matrix)

Synopsis

• Scripted functor: Ext

• Usage:

  Ext^i(M,f)

• Inputs:
  • i, an integer
  • M, a module
  • f, a matrix, N1 --> N2
• Outputs:
  • a matrix, the induced map $Ext^i(M,N1) \rightarrow{} Ext^i(M,N2)$

Description

If M is an ideal, it is regarded as a module in the evident way.

See also

• resolution -- projective resolution
• Tor -- Tor module
• Hom -- module of homomorphisms
• Ext^ZZ(Module,Module) -- Ext module
• Ext^ZZ(Matrix,Module) -- map between Ext modules