Differences between Python2 Sagemath and Python3 Sagemath?

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@slelievre thanks for finally clarifying what make ptest actually does. Previously I assumed that my python3 sage was failing make ptest only due to the documentation failing to build properly when using python3. Now I understand that it actually runs examples from different areas in mathematics. This means that if my use cases are calculus, vector calculus, ODES, algebra, Linear Algebra, Geometry and probability then using sage built with python3 will most likely not work adequately for some of these cases or even all.

Yes I already encountered failures referencing docs when running make ptest for sagemath compiled with python3. Can you confirm what failing the doctests means? I assume it means that I would have to look for documentation on the sagemath website instead.

I plan to use sage for calculus and vector calculus, ODES, algebra, Linear Algebra, Geometry. By worth the trouble I mean that do the gains from using sagemath python3 out weigh the problems one might encounter. For example, if the only issue is lack of an integrated documentation, then I would say using sagemath python 3 is worth the trouble (if it has better functionality) because I could always find documentation on the official sagemath website.

At this point, the only reasons to use Python 3 with Sage are: because you have a compelling reason to use Python 3 syntax rather than Python 2, and/or because you want to help make Sage compatible with Python 3. I don't know of any particular "better functionality" with Sage + Python 3.

I deleted python3 sage and restarted with python2, now I am getting a different error when running tests with SAGE_CHECK=yes.