Cannot create DatetimeIndex using Period

[jseabold]

This doesn't work. Looks like start and end should try a bit harder to convert to timestamp?

from datetime import datetime
pd.DatetimeIndex(start=pd.Period('1990q1'), end=datetime(1992, 12, 31), freq='Q')

This does.

pd.DatetimeIndex(start=pd.Period('1990q1').to_timestamp(), end=datetime(1992, 12, 31), freq='Q')

[jseabold]

I think the real issue is that Timestamp(period_instance) should work right?

[jreback]

yes it could work
just need to check if it's a Period then do to_timestamp

keeping in mind that it's defaulted to a start of the period

it could be that's why it's not automatic
as it's implicitly do a certain type of conversion eg start of period

[jseabold]

Yeah, I'm not sure what's best there actually. I just ran into another issue comparing datetime to period doesn't work, but it's not clear to me how it should actually work. End vs beginning of period defaults for Period are bound to be controversial.

Maybe it should just raise though maybe with a more informative error message? I don't like it (more work for me), but our code really should be more careful here and there's no real reason to assume beginning vs end of period mapping.

[jreback]

actually this does report a ValueError that it cannot convert. You think it should have a more informative message....ok..i'll bite (maybe noting that you can use to_timestamp)

[jseabold]

Yeah, I was just thinking something like

"Cannot convert Period to Timestamp unambiguously. Use to_timestamp"

[jreback]

sounds good to me