BC dates in Python

Question

I'm setting out to build an app with Python that will need to handle BC dates extensively (store and retrieve in DB, do calculations). Most dates will be of various uncertainties, like "around 2000BC".

I know Python's datetime library only handles dates from 1 AD.

So far I only found FlexiDate. Are there any other options?

EDIT: The best approach would probably be to store them as strings (have String as the basic data type) and -as suggested- have a custom datetime class which can make some numerical sense of it. For the majority it looks like dates will only consist of a year. There are some interesting problems to solve like "early 500BC", "between 1600BC and 1500BC", "before 1800BC".

Answer 1

Astronomers and aerospace engineers have to deal with BC dates and a continuous time line, so that's the google context for your search.

Astropy's Time class will work for you (and even more precisely and completely than you hoped). pip install astropy and you're on your way.

If you roll your own, you should review some of the formulas in Vallado's chapter on dates. There are lots of obscure fudge factors required to convert dates from Julian to Gregorian etc.