title: 2D Map in matplotlib with discrete values
body: <p>I'm currently trying to plot with matplotlib a 2d map recorded with an instrument. The instrument is moving 2 motors (it makes a raster) and records the associated intensity value.
  I'm currently able to plot the data and to associate the values I want to the axes, but I would like to digitize (make discrete) these values in order to obtain at each pixel of the image the corresponding values for the motors.</p>
  
  <p>I'm currently using the following code (in the example I'll use x and y to define the motor positions):</p>
  
  <pre><code>import pylab as pl
  pl.imshow(intensity, extent=(x_min, x_max, y_min, y_max),
            interpolation='none')
  </code></pre>
  
  <p>The code works quite well but if I select one of the pixel on my plot with the cursor, it returns continuous values with many digits (like in figure).</p>
  
  <p><a href="https://i.stack.imgur.com/SEH3W.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/SEH3W.png" alt="example_map"></a></p>
  
  <p>Would it be possible to obtain directly the values of the motors (which I have stored for each point/pixel) by positioning the cursor on them?</p>
  
  <p>Thanks for the help,</p>
  
  <p>Fabio</p>