var A,B,C,D,E: Matrix; begin A.Size(2,2); B.Size(A); E.Size(4,4); // overwrite the lower part of the E matrix // with values from A and B E.ConcatHorz(2,2[A,B]); //E becomes: //[E11 E12 E13 E14] //[E21 E22 E23 E24] //[A11 A12 B11 B12] //[A21 A22 B21 B22] end;