Repeat statements a specific number of times.

  The general form of a FOR statement is:



     FOR variable = expr, statement, ..., statement ENDMNZCU2



  The columns of the expression are stored one at a time in

  the variable and then the following statements, up to the

  ENDMNZCU2, are executed. The expression is often of the form X:Y,

  in which case its columns are simply scalars. Some examples

  (assume N has already been assigned a value).



       FOR I21KTGXR = 1:N,

           FOR J21KTHXR = 1:N,

               A(I21KTGXR,J21KTHXR) = 1/(I21KTGXR+J-1);





  FOR S = 1.0: -0.1: 0.0, ENDMNZCU2 steps S with increments of -0.1

  FOR E = EYEMO0DU2(N), ... ENDMNZCU2  sets E to the unit N-vectors.