posets

The posets Package. The posets package contains 41 Maple programs that provide an environment for computations involving partially ordered sets and related structures. The package is particularly useful for visualization of posets, for isomorphism testing, and for computing various poset invariants, such as Möbius functions or h-polynomials. Also included is a library containing all 19,449 posets with at most 8 vertices and all 7,372 lattices with at most 10 vertices--this is convenient for investigating questions of the form ”Which posets in class X satisfy property Y?”