title: Creating ticks in a matplotlib heatmap based on range of values
body: <p>I am creating a heatmap in matplotlib where on the x and y axis is some parameter of a measurement and the color represents the value of the measurement. Matplotlib automatically gives the axes ticks based on the index of the value. For example if on the x axis I am measuring at 50 different values the ticks will be from 0 to 50. However the real value of this parameter is for example from -30 to 80 and I would like matplotlib to create the ticks based on this minimum and maximum.</p>
  
  <p>I have tried using set_xticks but this requires the positions of the ticks as well as their labels. I am thinking that I should be able to just give matplotlib a min of -34 and max of 67 and have it create nice looking ticks placed at the proper positions but I haven't been able to find how.</p>