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SubalgebraBases :: Strategy

Strategy -- Update procedure for the Sagbi algorithm

Description

At the beginning of each loop inside of sagbi, the main SAGBIBasis computation object is updated. There are two types of update procedure; they are selected by setting Strategy to either \"DegreeByDegree\" or \"Incremental\". The \"DegreeByDegree\" strategy computes a partial groebner basis of the reduction ideal from scratch. The \"Incremental\" strategy computes a full groebner basis of the reduction ideal by using the previous full groebner basis together with the data of the new sagbi generators. The \"DegreeByDegree\" strategy is better when many new generators are added during each loop of the Sagbi algorithm. The \"Incremental\" strategy is better when there is little change to the number of sagbi generators. For many examples, it is observed that many new generators are added at the beginning of sagbi basis computations. Then towards the end of the computation, there are very few new generators that are added. By setting Strategy to \"Master\" (default), the \"DegreeByDegree\" strategy is used at the beginning and the strategy switches to \"Incremental\" part of the way through the algorithm.

See also

Functions with optional argument named Strategy :

For the programmer

The object Strategy is a symbol.