GLF - upper and lower bounds for nef cones
The Macaulay 2 package GLF.m2 by Diane Maclagan is
available here.
This requires Macaulay 2, which is available for
free download here.
This package takes as input a normal toric variety X_{Delta}, described by
giving the first lattice points on the rays of its fan, and the set of labels
of maximal cones in the fan. We do not assume that X_{Delta} is complete or
simplicial. The package then computes the lower and upper bound cones defined
in the paper
Lower and upper bounds for nef cones by Angela Gibney and Diane
Maclagan (arxiv.1009.0220).
Instructions for use:
- Save this file as GLF.m2 in a directory from which you can
start Macaulay 2.
- Start Macaulay 2 (type M2 at a terminal window, or bring up inside emacs).
- At the M2 prompt (or inside emacs), type installPackage "GLF",
and hit return or F11 (depending on whether you use a terminal window or emacs).
- Type viewHelp GLF and return/F11. This will bring up a browser
window with the documentation.
- The How to use this package page has information about the input
and output formats.
- The key commands are makeGcone, makeLcone,
and makeFcone. Look at their documentation pages for more examples of the
input format.
- The Examples menu contains extended examples computed in the
Gibney/Maclagan paper.
Note: This package had to be rewritten slightly to accommodate changes
in Macaulay 2 version 1.4. Please redownload it if a previous version
is now refusing to load.
Site maintained by Diane Maclagan. Last updated November 11, 2010.