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DA.DiffTO

Matrix corresponding to predefined differential term orderings.
Syntax
          
DA.DiffTO(D:STRING):MAT

          

Description
This function returns the matrix corresponding to the indicated term ordering D.

Example
-- Assume that the current ring is given by QQ[x[1..n,0..m]]. 
-- Then D can be one of the following values:
-- "Lex":     Lexicographic ordering with 1 T iff Deg(S) > Deg(T) or Deg(S) = Deg(T) and S >_Lex T
-- "WLex":    S > T iff Weight(S) > Weight(T) or Weight(S) = Weight(T) and S >_Lex T
-- "Ord":     Lexicographic ordering with 1 T iff Deg(S) > Deg(T) or Deg(S) = Deg(T) and S >_Ord T
-- "WOrd":    S > T iff Weight(S) > Weight(T) or Weight(S) = Weight(T) and S >_Ord T
--
-- Use as follows:
Use QQ[x[1..1,0..20]];
Use QQ[x[1..1,0..20]], Ord(DA.DiffTO("Lex"));


See Also