title: How to plot same value until it change?
body: <p>I have data in file and they have date/time point and value. The line in data is written only when value change. For example:</p>
  
  <pre><code>10:01  12.00
  10:12   8.00
  10:14   9.00
  </code></pre>
  
  <p>I would like to plot a graph which will not draw line straight from one point to other, drawing declining line, but keep horizontal line until point 10:12 and then jump to value 8.00 and then keep horizontal line in value 8.00 until end then jumping to 9.00</p>
  
  <p>I was searching around, but the challenge is that I have no idea what is proper name of such a graph. I hope you can help me to draw it in gnuplot. Thank you in advance.</p>