Difference between revisions of "ApCoCoA-1:DA.DiffTO"

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(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):MATRIX
+
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&lt;x[1,0]&lt;x[1,1]&lt;x[1,2]&lt;...&lt;x[2,0]&lt;x[2,1]&lt;... 
-- <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&lt;x[1,0]&lt;x[2,0]&lt;...&lt;x[1,1]&lt;x[2,1]&lt;...
-- <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>));

DA.Weight