title: Gnuplot: Errorbars with variable style
body: <p>I want to plot data with errorbars, where the points are quite dense and have  rather different errors. I would like the "good" points (i.e. small error) to be quite prominent, and the "bad" points (i.e. large error) to be less visible, because I don't want the bad points to dominate the overall picture. This could be achieved by dynamically changing the line width or transparency. </p>
  
  <p>What I come up so far is to use a hard cut-off and plot the data twice: All points with a small error (&lt;=0.1) with a solid line colour, and all points with a large error (>0.1) with increased transparency.</p>
  
  <pre><code>$data &lt;&lt; EOD
  535.66534   1.553616310747869   0.08061677996455376
  536.15027   1.520824866288427   0.05828386048268186
  537.38049   1.332803196338175   0.235778491140896
  537.64696   1.479699311985051   0.3751992204089783
  540.20631   1.497105281091503   0.04237229839015798
  541.41537   1.320918189513518   0.4115091427635642
  542.00647   1.47517488483194    0.3873921664923128
  543.51616   1.515846650015762   0.0471200695087297
  545.00234   1.538963623338375   0.1611245310026408
  556.4311    1.606343443386191   0.04973685496066002
  EOD
  plot $data u 1:($3&gt;0.1 ? 1/0 : $2):3 w yerrorbars lc 1, '' u 1:($3&lt;=0.1 ? 1/0 : $2):3 w yerrorbars lc rgb "#aa9400d3"
  </code></pre>
  
  <p>But this is a rather hard-coded solution. A more dynamic picture, where each point's transparency is individually calculated from the size of its error, would be nicer and smoother. Does anyone have an idea how to achieve this? Alternate suggestions for "hiding" bad points are welcome as well!</p>