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MatFacCurvesP4 :: h1NormalBundle

h1NormalBundle -- computes h^1 of the normal sheaf

Synopsis

Usage:
h1NormalBundle(I,X)
Inputs:
- I, an ideal, the ideal of a curve in Pⁿ, n >= 3
- X, an ideal, the ideal of a hypersurface containing the curve
Outputs:
- M, a module, the H¹ of the normal sheaf of the curve with respect to the hypersurface

Description

i1 : S = ZZ/32009[x_0..x_3];

i2 : I = monomialCurveIdeal(S,{1,2,3});

o2 : Ideal of S

i3 : X = ideal(gens I * random(source gens I,
             S^{1:-min(degrees source gens I)}));

o3 : Ideal of S

i4 : time h1NormalBundle(I,X)
     -- used 0.00675235 seconds

o4 = 0

       ZZ
o4 : ------module
     32009

Caveat

This function might require quite an amount of time to run, depending on the input data.

Ways to use `h1NormalBundle` :

h1NormalBundle(Ideal,Ideal)