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SectionRing :: isMRegular

isMRegular -- isMRegular(F,G,m) tests where F is m-regular with respect to G (globally generated) in the sense of Castelnuovo-Mumford. Omitting G assumes G=O_X(1).

Synopsis

Description

isMRegular(F,G,m) tests definition 1.8.4 of Lazarsfeld’s Positivity in Algebraic Geometry I, which is to say whether Hi(F ⊗G(m-i)) = 0 for every i>0. It tests (in this order) H1, H2, ..., Hdim(X), and stops as soon as a non-zero cohomology is found. If none is found, F is m-G-regular, and it outputs true.

Ways to use isMRegular :