ApCoCoA-1:DA.DiffTO
From ApCoCoAWiki
| This article is about a function from ApCoCoA-1. |
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.
@param D Name of a predefined differential term ordering.
@return The matrix corresponding to the predefined term ordering.
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<x[1,0]<x[1,1]<x[1,2]<...<x[2,0]<x[2,1]<...
-- "DegLex": S > 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<x[1,0]<x[2,0]<...<x[1,1]<x[2,1]<...
-- "DegOrd": S > 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"));
