Difference between revisions of "ApCoCoA-1:DA.DiffTO"
From ApCoCoAWiki
(Corrected example.) |
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<short_description>Matrix corresponding to predefined differential term orderings.</short_description> | <short_description>Matrix corresponding to predefined differential term orderings.</short_description> | ||
<syntax> | <syntax> | ||
− | DA.DiffTO(D:STRING): | + | DA.DiffTO(D:STRING):MAT |
</syntax> | </syntax> | ||
<description> | <description> | ||
− | This function returns the matrix corresponding to the indicated term ordering D. | + | This function returns the matrix corresponding to the indicated term ordering <tt>D</tt>. |
<itemize> | <itemize> | ||
<item>@param <em>D</em> Name of a predefined differential term ordering.</item> | <item>@param <em>D</em> Name of a predefined differential term ordering.</item> |
Revision as of 12:46, 7 July 2009
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: -- <quotes>Lex</quotes>: Lexicographic ordering with 1<x[1,0]<x[1,1]<x[1,2]<...<x[2,0]<x[2,1]<... -- <quotes>DegLex</quotes>: S > T iff Deg(S) > Deg(T) or Deg(S) = Deg(T) and S >_Lex T -- <quotes>WLex</quotes>: S > T iff Weight(S) > Weight(T) or Weight(S) = Weight(T) and S >_Lex T -- <quotes>Ord</quotes>: Lexicographic ordering with 1<x[1,0]<x[2,0]<...<x[1,1]<x[2,1]<... -- <quotes>DegOrd</quotes>: S > T iff Deg(S) > Deg(T) or Deg(S) = Deg(T) and S >_Ord T -- <quotes>WOrd</quotes>: 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(DiffTO(<quotes>Lex</quotes>));