ApCoCoA-1:DA.DiffTO
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Revision as of 09:53, 8 December 2008 by S schuster (talk | contribs) (New page: <command> <title>DiffTO</title> <short_description>Returns the matrix corresponding to predefined differential term orderings.</short_description> <syntax> DA.DiffTO(D:STRING):MATRIX </syn...)
DiffTO
Returns the matrix corresponding to predefined differential term orderings.
Syntax
DA.DiffTO(D:STRING):MATRIX
Description
This function returns the matrix corresponding to the indicated term ordering D.
Assume that the current ring is given by Q[x[1..n,0..m]]. Then D can be one of the following values:
| S (as STRING) | Corresponding term ordering |
|---|---|
| "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 |
Example
Use Q[x[1..1,0..20]], Ord(DiffTO("Lex"));
