# Monoid

### From Glossary

A set, , defined on rational
vectors, such that: (1) , and (2) if are in , then
is in The monoid is *integral* if it contains only
integer vectors. One can think of a monoid as a discrete analogue
of a convex cone.

A set, , defined on rational
vectors, such that: (1) , and (2) if are in , then
is in The monoid is *integral* if it contains only
integer vectors. One can think of a monoid as a discrete analogue
of a convex cone.