ContinuumIO/blaze — pull request #660 by mrocklin (2014-09-22 15:24:40+00:00)
Title: Add frequencies attribute to tableexprs

This shortcuts to `by(self, count=self.count())` I find myself doing this often enough that it might be useful.

Thoughts on the name? Is there a better API? Pandas.Series uses value_counts. Toolz uses frequencies. `counts` might work but it conflicts with `count`.