Unify the definition of "monomial", introduce "term"

[boothby]

Consider:

    sage: R.<x> = QQ[]
    sage: S.<u,v> = QQ[]
    sage: f = 2*x
    sage: g = 2*u
    sage: f.is_monomial()
    True
    sage: g.is_monomial()
    False

According to Wikipedia, there are two conventions on the matter, and we should support both. I propose that we accept neither f nor g as monomials, and add the method is_term:

    sage: f.is_monomial()
    False
    sage: g.is_monomial()
    False
    sage: f.is_term()
    True
    sage: g.is_term()
    True

Component: commutative algebra

Keywords: sd32

Reviewer: William Stein

Issue created by migration from https://trac.sagemath.org/ticket/11746

[williamstein]

comment:1

This dup surely wouldn't happen if we were sitting right next to each other (which we are)! :-)

[nexttime]

Reviewer: William Stein