title: convert numpy array of tuples to 2D array
body: <p>I have a pandas DataFrame in which one of the columns is made of tuples of floats. When I use <code>arr = df['col_name'].to_numpy()</code>, I end up with a 1D array of tuples, but I need a 2D array of floats.</p>
  
  <p>My solution so far is to use <code>arr = np.array(df['col_name'].to_list())</code>. This works, but it seems inefficient to convert first to a list and then to an array. So I'm wondering, is there a better way to do this?</p>
  
  <p><a href="https://stackoverflow.com/q/32422764/10863323">This question</a> is related, but the only answer there points to reading a text file differently, which is not an option for me since the data is already in the DataFrame.</p>