proposition: Lemma subid_tr_mxvec m n (I : 'M[R]_(m,n)) : ((mxvec I)^T <= (mxvec I^T)^T)%IS.
proof: Proof. apply/subid_colP => i /=; case: (mxvec_indexP i) => {}i j. by rewrite (subid_trans _ (subrid (mxvec_index j i) _)) // !(mxE, mxvecE). 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