2001/01/12 by Brian Harbourne, Harbourne, Brian
Computer Science · Mathematics · #Algebraic Geometry and Number Theory #Commutative Algebra and Its Applications #Polynomial and algebraic computation #math.AC #math.AG #msc:13P10 #msc:14C99
paper · pdf · doi:10.48550/arxiv.math/0101112
46 pages PlainTeX (includes 23 pages of Macaulay 2 scripts which can be copied and pasted directly into Macaulay)
arxiv created 2001/01/12 · arxiv updated 2009/11/30
This paper surveys certain problems involving numerical characters for ideals I(Z) defining fat points subschemes Z=m1p1+...+mnpn for general points pi∈ \bf P2. It also presents some new results, and includes a suite of MACAULAY 2 scripts for computing actual or conjectured values of (or bounds on) these characters. One such script, for example, is findres, which implements an algorithm due to Fitchett, Harbourne and Holay for computing the syzygy modules in a minimal free resolution of the ideal I(Z) for any such Z with n<=8; since findres does not rely on a Gröbner basis calculation, it is very fast and can handle very large multiplicities.