day_of_week year 0 bug

[andy-theia]

Describe the bug
The day_of_week function returns the incorrect value for the first 60 days of year 0 (Jan 1 - Feb 29)

Provide the following:

• Example:
• dow = day_of_week(0,1,1)
• ; dow = 0
• Should return 6

Computing environment

• OS: Mac
• OS version: MacOS 14.3.1
• NCL Version: 6.6.2
• Installation method: conda

Additional context

[Dave-Allured]

Invalid function input. Function documentation says "Gregorian calendar only". Year 0 is not in the Gregorian calendar.

If you need a function to compute day of week for artificial years not in Gregorian calendar, such as year 0, then please write a custom function to calculate this.

Please close this issue. Thank you.

[kafitzgerald]

Thanks for noting that.

Interestingly the function fails for years <0, but does allow for year 0. I think this is what prompted logging the issue if I recall correctly. Though it seems that's more of an issue with the checks than the function itself working as intended.