proposition: Lemma msuppZ_le c g : msupp (c *: g) `<=` msupp g.
proof: Proof. apply/fsubsetP=> k; rewrite -!mcoeff_neq0 mcoeffZ. by apply/contraTneq=> ->; rewrite mulr0 negbK. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat) mathcomp(seq path choice finset fintype finfun) mathcomp(tuple bigop ssralg ssrint ssrnum) xfinmap