title: Using Numpy arrays as lookup tables
body: <p>I have a 2D array of Numpy data read from a .csv file. Each row represents a data point with the final column containing a a 'key' which corresponds uniquely to 'key' in another Numpy array - the 'lookup table' as it were.</p>
  
  <p>What is the best (most Numpythonic) way to match up the lines in the first table with the values in the second?</p>