Non-standard Calendar Support

The current datetime64 API only supports the standard Gregorian calendar. In the climate science community (and presumably others), a number of other calendars systems are used, for example:

• Julian Calendar
• No Leap Day Calendar: Gregorian calendar without leap years, i.e., all years are 365 days long.
• All Leap Day Calendar: Gregorian calendar with every year being a leap year, i.e., all years are 366 days long.

I’d like to propose adding calendar support to the datetime64 API with the hope that changes here will trickle down into pandas and xray.

I’m not sure exactly how I’d like to see the API and would like to hear from those familiar with datetime64 on how it could be done. Of course, the default calendar behavior should remain the Gregorian calendar.

xref: https://github.com/xray/xray/issues/521, https://github.com/xray/xray/pull/523, https://github.com/pydata/pandas/issues/7307 cc: @shoyer @rabernat @ocefpaf

[akturner]

👍 This would be very useful in the climate modeling community. Several IPCC class models need this functionality to analyze output.

[njsmith]

@CommonClimate:

Being relatively new at Python, it’s not something that I could do myself, but I am good at finding funding for important projects, and this is very high priority for me. PM me.

I don’t think github has any PM facility and your profile’s pretty anonymous, but if you want to talk offline you can reach me at [e-mail]