while loop

        The RLaB while statement is similar to the C while statement.

        Example:

        > i=1;
        > while(i<10)
          {
            a[i] = 1.3*i;
            i++;
          }
        > a
         a =
         matrix columns 1 thru 5
                 1.3         2.6         3.9         5.2         6.5
        
         matrix columns 6 thru 9
                 7.8         9.1        10.4        11.7

        while(0) { "this will never be executed" }

        If the conditional evaluates to zero then the loop is not
        executed, if it evaluates to anything other than zero it will
        be executed until the condition is zero.