title: how to plot mean and standard deviation of multiple measures in gnuplot
body: <p>I'd like to plot mean and standard deviation of multiple measures in one Gnuplot, if possible.</p>
  
  <p>For example, object A and B has measures of lengths and weights like this (CSV format):</p>
  
  <pre><code>length,weight
  100.0,0.1
  100.5,0.12
  98.8,0.09
  100.1,0.11
  </code></pre>
  
  <p>Is it possible to plot this in a single figure with good visibility, i.e., the length is at the magnitude of 100, while the weight is at 0.1? I don't want the logarithmic way because in my real data, it doesn't make sense to logarithmize them. </p>
  
  <p>Yerrorlines seems an option, but can histogram do this too?
  Anyone knows how to do so in Gnuplot?
  Thanks!</p>