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RationalMaps :: SimisStrategy

SimisStrategy -- A strategy for inverseOfMap, isBirationalMap and isEmbedding.


It is a valid value for the Strategy Option for inverseOfMap (and other functions). Considering the bigraded structure of the equations of the ideal of definition of Rees algerba, SimisStrategy is looking for all Grobner basis with first degree 1. The advantage of this restriction is that only this part of the Rees ideal is enough to decide Birationality and to compute the inverse map; so that this Strategy reduces the number of computations. A disadvatage of this Strategy is that if the given map is not birational this Strategy may never end because the jacobianDualMatrix will not attain its maximum rank. To circumvent this problem we consider HybridStrategy.

See also

For the programmer

The object SimisStrategy is a symbol.