pandas.DatetimeIndex.is_month_start#

property DatetimeIndex.is_month_start[source]#

Indicates whether the date is the first day of the month.

This boolean attribute evaluates to True if the date falls on the first day of a calendar month, and False otherwise. If the index has a business freq (e.g. "BMS"), the result follows that frequency’s month boundaries instead of the calendar’s.

See also

DatetimeIndex.is_month_end: Return a boolean indicating whether the date is the last day of the month.

Examples

>>> idx = pd.date_range("2018-02-27", periods=3)
>>> idx.is_month_start
array([False, False,  True])