Converting between datetime and Pandas Timestamp objects
PythonDatetimePandasPython Problem Overview
I have the following:
> date1
Timestamp('2014-01-23 00:00:00', tz=None)
> date2
datetime.date(2014, 3, 26)
and I read on this answer that I could use pandas.to_datetime() to convert from Timestamps to datetime objects, but it doesn't seem to work:
> pd.to_datetime(date1)
Timestamp('2014-01-23 00:00:00', tz=None)
Why? How can I convert between these two formats?
Python Solutions
Solution 1 - Python
You can use the to_pydatetime method to be more explicit:
In [11]: ts = pd.Timestamp('2014-01-23 00:00:00', tz=None)
In [12]: ts.to_pydatetime()
Out[12]: datetime.datetime(2014, 1, 23, 0, 0)
It's also available on a DatetimeIndex:
In [13]: rng = pd.date_range('1/10/2011', periods=3, freq='D')
In [14]: rng.to_pydatetime()
Out[14]:
array([datetime.datetime(2011, 1, 10, 0, 0),
datetime.datetime(2011, 1, 11, 0, 0),
datetime.datetime(2011, 1, 12, 0, 0)], dtype=object)
Solution 2 - Python
Pandas Timestamp to datetime.datetime:
pd.Timestamp('2014-01-23 00:00:00', tz=None).to_pydatetime()
datetime.datetime to Timestamp
pd.Timestamp(datetime(2014, 1, 23))
Solution 3 - Python
>>> pd.Timestamp('2014-01-23 00:00:00', tz=None).to_datetime()
datetime.datetime(2014, 1, 23, 0, 0)
>>> pd.Timestamp(datetime.date(2014, 3, 26))
Timestamp('2014-03-26 00:00:00')
Solution 4 - Python
To answer the question of going from an existing python datetime to a pandas Timestamp do the following:
import time, calendar, pandas as pd
from datetime import datetime
def to_posix_ts(d: datetime, utc:bool=True) -> float:
tt=d.timetuple()
return (calendar.timegm(tt) if utc else time.mktime(tt)) + round(d.microsecond/1000000, 0)
def pd_timestamp_from_datetime(d: datetime) -> pd.Timestamp:
return pd.to_datetime(to_posix_ts(d), unit='s')
dt = pd_timestamp_from_datetime(datetime.now())
print('({}) {}'.format(type(dt), dt))
Output:
(<class 'pandas._libs.tslibs.timestamps.Timestamp'>) 2020-09-05 23:38:55
I was hoping for a more elegant way to do this but the to_posix_ts is already in my standard tool chain so I'm moving on.