title: how to plot a step function in scilab
body: <p>I am trying to create a step function in scilab, that jumps between two values {28,36} and stays on each for 5 units of 'i'.<br>
  Here is my code;</p>
  
  <pre><code>    for i=1:25;
          if pmodulo(i,5)==0
               if a==28
                  a=36
               else
                  a=28
               end
          end
      end
      plot(i,a)
  </code></pre>
  
  <p>can some one please tell me what am missing, cause i keep getting a plot screen with no graph and my i-axis in the plot screen has values from 20 to 25 instead of 1 to 25, which tells me am doing something wrong</p>