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mRegularity -- Castelnuovo-Mumford regularity

Synopsis

Description

Example:

computing the regularity of the defining ideal of the second Veronesean of P3

i1 : R=QQ[a,b,c,d,x_0..x_9,MonomialOrder =>  Eliminate 4];
i2 : i=ideal( x_0-a*b,x_1-a*c,x_2-a*d,x_3-b*c,x_4-b*d,x_5-c*d,x_6-a^2,x_7-b^2,x_8-c^2,x_9-d^2);

o2 : Ideal of R
i3 : j=selectInSubring(1, gens gb i);

             1       20
o3 : Matrix R  <--- R
i4 : I=ideal flatten entries j; -- this is the ideal of the Veronesean

o4 : Ideal of R
i5 : mRegularity I

o5 = 3

This symbol is provided by the package Regularity.

See also

Ways to use mRegularity :