" CS 1621 Fall 2005
  Simple demonstration of a new subclass of Array to
  represent 2-dimensional data"

| m1 m2 m3 m4 |
m1 := TwoDArray rows: 3 cols: 5.
m2 := TwoDArray rows: 3 cols: 5.
1 to: (m1 getrows) do: [ :i |
      1 to: (m1 getcols) do: [ :j |
            m1 atrow: i atcol: j put: (i+j).
            m2 atrow: i atcol: j put: (i*j).
      ].
].
m3 := m1 + m2.
(m1 printString) printNl.
' + ' printNl.
(m2 printString) printNl.
' = ' printNl.
(m3 printString) printNl.

" The statements below will produce an error because the
  arrays are not compatible.  We could take a less extreme action if
  we wished"
m4 := TwoDArray rows: 4 cols: 5.
m3 := m1 + m4.
!