title: How to export from gnuplot to extern datafile the frequency counts used to generate a histogram?
body: <p>To plot a histogram I follow the book Gnuplot in Action and I use</p>
  
  <pre><code>binc(bin_width,x) = bin_width * ( int(x/bin_width) + 0.5 )
  </code></pre>
  
  <p>and to plot I use</p>
  
  <pre><code>plot 'datafile' u (binc(bin_width,$1)) : (1.0/size_sample ) smooth frequency
  </code></pre>
  
  <p>I have understood that smooth frecuency create a frecuency count for each bin and this is used by plot to make the histogram</p>
  
  <p>But, How can I create a variable that contain the frecuency, I want do this to export the values of each bin's frecuency counts to a file, for example.</p>