title: How can I join columns by DatetimeIndex, matching day, month and hour from data from different years?
body: <p>I have a dataset with meteorological features for 2019, to which I want to join two columns of power consumption datasets for 2017, 2018. I want to match them by hour, day and month, but the data belongs to different years. How can I do that?</p>
  
  <p><a href="https://i.stack.imgur.com/qGatb.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/qGatb.png" alt="Power consumption dataset"></a></p>
  
  <p>The meteo dataset is a 6 column similar dataframe with datetimeindexes belonging to 2019.</p>