Timestamp seconds change when converting from T and Z to datetime

Question

I have two timestamps

starttime = '2020-10-13T13:42:01Z'
endtime = '2020-10-13T13:42:21Z'

When I convert it to datetime, the seconds of the timestamp changes

timestampstart = pd.to_datetime(starttime, format="%Y-%m-%dT%H:%M:%S%fZ")
timestampend = pd.to_datetime(endtime, format="%Y-%m-%dT%H:%M:%S%fZ")

print(timestampstart,timestampend)
2020-10-13 13:42:00.100000 2020-10-13 13:42:02.100000

My required output is

2020-10-13 13:42:01 2020-10-13 13:42:21

What is the problem? How can I tackle it?

You have no fractional seconds `%f` in your input strings. In general, you don't need to specify `format` here. The format is pretty standard, ISO8601. — FObersteiner, Oct 13 '20 at 14:37
so i have to just convert to datetime without mentioning format? — phoenix, Oct 13 '20 at 15:22
Yes, here you can convert to datetime with just e.g. `pd.to_datetime(starttime)`. — FObersteiner, Oct 13 '20 at 20:16

score 1 · Accepted Answer · answered Oct 14 '20 at 05:46

As commented, your timestamps are formatted according to ISO8601. The T separates date and time, the Z stands for "zulu time", i.e. UTC. The correct strptime format code would be

'%Y-%m-%dT%H:%M:%S%z'

Note that there are no fractional seconds (%f) and instead of a literal Z, you should use %z to convert the Z to UTC. You could also use Python datetime.fromisoformat for parsing with a little tweak, see e.g. here.

But: since the format is standardized and you seem to be working with pandas, you can automatically parse as e.g.

import pandas as pd
pd.to_datetime('2020-10-13T13:42:01Z')

Out[3]: Timestamp('2020-10-13 13:42:01+0000', tz='UTC')

Timestamp seconds change when converting from T and Z to datetime

1 Answers1