suggestions for faster busiest date calculation

[markusstraub]

I noticed that the method for calculating the busiest date for a takes quite a long time and had a look at it. For a real-world sized feed of mine the proposed changes reduced the time from 5 minutes to 2:40.

Tests still pass and comparing the extracted feeds from my test script also showed an empty diff.

[araichev]

Thanks, @markusstraub .
I'll review this as soon as i get a chance.

[araichev]

Hi @markusstraub , i finally got around to review this merge request.
I've taking your idea of using a set_index instead of a groupby, which should speed things up.
Precomputing weekday strings, doesn't look like it would speed things up, because you're still doing the same number of conversion calculations.
But try out the new release and let me know.

[markusstraub]

Great, thanks for incorporating the change, hope it helps you and all other users :) (I'll test this the next time I have to fiddle with GTFS)