title: Gnuplot - Comparing several boxplot pairs in one picture
body: <p>(Edit: Histogram removed, not relevant and confusing.)</p>
  
  <p>I want a <strong>boxplot</strong> which can visualize statistical data. I made <strong>two data files</strong> for two types of data. In the first column the level, which is the x value, is written, in the second column the value. One line for each data point, several points per level. I want the <strong>same levels</strong> in the different files <strong>compared</strong> next to each other. I came up with the following code:</p>
  
  <pre><code>Tournament5 = "#99ffff"; Sigmascaling = "#4671d5"
  set terminal pngcairo
  set output "generations_dev.png"
  set yrange [0:17.5]
  set ylabel "Maximum Compactness of Best Solutions"
  set xlabel "Number of Generations"
  
  set autoscale fix
  
  set style fill solid 0.25 border -1
  set style boxplot nooutliers pointtype 7 separation 3
  set style data boxplot
  set boxwidth 1
  
  plot "generation_tour.data" using (1.0):2:(0):1, "generation_sig.data" using (2.0):2:(0):1
  </code></pre>
  
  <p>which gives me the following picture:
  <a href="https://i.stack.imgur.com/RnC3A.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/RnC3A.png" alt="boxplot"></a></p>
  
  <p><strong>Now my problems/questions are:</strong></p>
  
  <ul>
  <li>Why are the x values not stretched to the right but only to the
  middle? This happens when I add the second file, with just one file it uses the full width of the graphic.</li>
  <li>I only need one x label for each pair but I get it two times, how can I supress one?</li>
  </ul>
  
  <p>Thank you for any help!</p>
  
  <p><a href="http://s000.tinyupload.com/index.php?file_id=55926117015315657865" rel="nofollow noreferrer">Data File generation_sig.data</a></p>
  
  <p><a href="http://s000.tinyupload.com/index.php?file_id=66557369568677334663" rel="nofollow noreferrer">Data File generation_tour.data</a></p>