var a: MatrixInt; b: VectorInt; begin a.SetIt(3,3,[1,2,3,4,5,6,7,8,9]); a.Select(0,2); //a = [1,2] a.DisableSelect; a.Select(2,2); //exception raised here b.Select(a,2,2); //but this will work a.SelectAll; //b is not changed, it still points to [4,5] end;