title: Pandas - Combine df.loc for multiple operations?
body: <p>Is there a way to perform one <code>df.loc</code> lookup, but then perform multiple operations on the subset of rows? </p>
  
  <p>Here's the motivation. I have 2 dataframes with data on the same users. I am looping over <code>df_2.groupby('user_id')</code> and then look up on the other dataframe to assign some values: </p>
  
  <pre><code>for user, user_df in df_2.groupby('user_id'):
      df_1.loc[df_1.user_id == user, 'value_1'] == user_df.value_1.mean()
      df_1.loc[df_1.user_id == user, 'value_2'] == user_df.value_2.min()
  </code></pre>
  
  <p>could I combine these in some way to perform just one df.loc, but assign both values? </p>