This package defines Poset as a new data type and provides routines which use or produce posets. A poset (partially ordered set) is a set together with a binary relation satisfying reflexivity, antisymmetry, and transitivity.
Contributors:
The following people have generously contributed code to the package: Kristine Fisher, Andrew Hoefel, Manoj Kummini, Stephen Sturgeon, and Josephine Yu.
Other acknowledgements:
A few methods in this package have been ported from John Stembridge’s Maple package implementing posets, which is available at http://www.math.lsa.umich.edu/~jrs/maple.html#posets. Such methods are noted both in the source code and in the documentation.
Version 1.1.2 of this package was accepted for publication in volume 7 of the journal The Journal of Software for Algebra and Geometry on 5 June 2015, in the article Partially ordered sets in Macaulay2. That version can be obtained from the journal or from the Macaulay2 source code repository, http://github.com/Macaulay2/M2/blob/master/M2/Macaulay2/packages/Posets.m2, commit number 3a8d880a524f36a9668750375bb6079a7b00ea0f.