title: Adding error bars on a bar graph in gnuplot
body: <p>I have the following file I want to plot using gnuplot bar graphs: </p>
  
  <pre><code>Function X X-ERROR Y Y-ERROR
  A 1.311539 0.066268 1.000000 0.000000
  (a1,b0)  1.325429 0.083437 1.010926 0.016710
  (a.9,.b1)  1.134640 0.040017 1.276168 0.060281
  (a.8,.b2)  1.078336 0.058529 1.346358 0.054645
  (a.7,.b3)  1.035866 0.060660 1.318395 0.018087
  (a.6,.b4)  0.982717 0.047363 1.196714 0.047427
  (a.5,.b5)  0.962423 0.051994 1.127991 0.044731
  (a.4,.b6)  0.953673 0.046014 1.139608 0.044726
  (a.3,.b7)  0.948948 0.050462 1.169209 0.044333
  (a.2,.b8)  0.941013 0.047166 1.198138 0.045844
  (a.1,.b9)  0.929961 0.057801 1.328111 0.088813
  (a0,b1)  0.966331 0.036079 3.289381 0.213192
  B  1.000000 0.000000 3.321802 0.121290
  </code></pre>
  
  <p>I can manage to plot the graph perfectly using: </p>
  
  <pre><code>plot 'file.dat' using 4:xtic(1) title col, \\
          '' using 2:xtic(1) title col;
  </code></pre>
  
  <p>However I would like to use columns 3 and 5 to represent the interval of confidence that I always calculated. Any help?</p>
  
  <p>Thanks! </p>