proposition: Lemma sub_addid0l m n (I : 'cV[R]_n) : (I <= (0 : 'cV[R]_m) +i I)%IS.
proof: Proof. exact: (subid_trans (sub_addid0r _ _) (subid_addC I 0)). Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq path) mathcomp(ssralg fintype perm choice fingroup) mathcomp(matrix bigop zmodp mxalgebra poly) ssrcomplements