Package sagbi/SB.GetTruncDeg

From ApCoCoAWiki
This article is about a function from ApCoCoA-2.

SB.GetTruncDeg

This function returns the truncation degree of the currently stored SAGBI basis in the given subalgebra.

Syntax

SB.GetTruncDeg(S: TAGGED("$apcocoa/sagbi.Subalgebra")): INT

Description

   </itemize>
  • @param S A subalgebra

  • @return 0 if there is no (truncated) SAGBI basis stored in S, -1 if there is a complete SAGBI basis stored in S and d if there is a d-truncated SAGBI basis stored in S.

Example

Use R ::= QQ[x,y];
fs := [x^2*y,  x^2 -y^2,  x^2*y^2 -y^4,  x^2*y^4];
S := SB.Subalgebra(R,fs);
PrintLn SB.GetTruncDeg(S); -- 0
PrintLn SB.GetTruncSAGBI(ref S,4); -- [x^2 -y^2,  x^2*y,  x^2*y^2 -y^4]
PrintLn SB.GetTruncDeg(S); -- 4
PrintLn SB.GetSAGBI(ref S); -- [x^2 -y^2,  x^2*y,  x^2*y^2 -y^4,  y^6,  x^2*y^4]
PrintLn SB.GetTruncDeg(S); -- -1

See also

HowTo:Term Orderings

Package sagbi/SB.TruncSAGBI

Package sagbi/SB.SAGBI

Package sagbi/SB.GetTruncSAGBI

Package sagbi/SB.GetID

Package sagbi/SB.GetRing

Package sagbi/SB.GetGens

Package sagbi/SB.GetCoeffRing

Package sagbi/SB.GetSAGBI

Package sagbi/SB.GetLTSA

Package sagbi/SB.GetInDeg

Package sagbi/SB.GetHS