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Dmodules :: localCohom(..., Strategy => ...)

localCohom(..., Strategy => ...) -- specify strategy for local cohomology

Description

This option together with LocStrategy determines a strategy for localCohom(...Ideal...) and localCohom(...Ideal, Module...).
  • Walther -- the algorithm of U. Walther that uses Cech complex.
  • LocStrategy => null -- used only for localCohom(...Ideal...), localizations are done by straitforward computation of annihilators and b-polynomials as described in [1].
  • LocStrategy => OaTaWa -- localizations are done following Oaku-Takayama-Walther method.
  • LocStrategy => Oaku -- localizations are done following Oaku's algorithm.
  • OaTa -- restriction algorithm is used, which is due to T. Oaku and N. Takayama [2]
For detailed description of the algorithms see
  • [1]U. Walther, Algorithmic computation of local cohomology modules and the local cohomological dimension of algebraic varieties (JPAA (139), 1999.)
  • [2]Oaku, TakayamaAlgorithms for D-modules...

Further information