for m, n being Nat
for K being Field
for a being Element of K
for nt being Element of n -tuples_on NAT
for mt being Element of m -tuples_on NAT
for M being Matrix of K st [:(rng nt),(rng mt):] c= Indices M holds
a * (Segm (M,nt,mt)) = Segm ((a * M),nt,mt)