proposition: Lemma map_submx m1 m2 n (A : 'M_(m1, n)) (B : 'M_(m2, n)) : (A^f <= B^f)%MS = (A <= B)%MS.
proof: Proof. by rewrite !submxE -map_cokermx -map_mxM map_mx_eq0. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype finfun bigop finset fingroup perm order) mathcomp(div prime binomial ssralg finalg zmodp matrix)