Calendar.groupby#

Calendar.groupby(grouper)#

Group dates by the grouper parameter.

Allowed values for the grouper:

  • callable - the callable will receive the date and must return a hashable value

  • frequency criterion - a string representing a frequency

Frequency criteria include:

  • W: group by week number each year (same as W-SUN)

  • W-MON: to W-SUN group week ending on a particular weekday

  • M: group by month each year

  • Q: group by quarter each year

  • H: group by semester each year

  • Y: group by year each year

Parameters:

grouper (str, callable) – the criterion to group dates by

Returns:

Collection of calendars

Return type:

doubledate.calendar.Collection

Example

Group dates by month

>>> calendar = Calendar(dates)
>>> calendar.groupby("M")
<doubledate.Collection at 0x7fd0fa52c2e0>

Group dates in half months

>>> calendar = Calendar(dates)
>>> calendar.groupby(lambda date: (date.year, date.month, date.day < 15))
<doubledate.Collection at 0x7fd0fa52c2e0>