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sub, rsub and isub

See original GitHub issue

I’d propose a behavior change of the __sub__ operator to align with how the other operators work. Right now v - w will do the equivalent of v + (-w) where the neg takes the inverse of w. I think it should align instead with what __add__ does and use v.eadd(w, add_op=MINUS). The old behavior can still be had by adding the negation. This makes all the binary operations consistent, and allows me to make a scalar construction like w - 5 which would become w.apply_second(MINUS, 5). Any thoughts @szarnyasg and @marci543 ? I made a PR #69.

Issue Analytics

State:
Created 3 years ago
Comments:7 (4 by maintainers)

Top GitHub Comments

1reaction

michelpcommented, Aug 13, 2020

And you know, the more I think about it, + and * maybe aren’t the best map to eWiseAdd and eWiseMult which are really much more like & (union) and | (intersection) operations that just happen to default to plus and times operations and the actual math operations are just nice shortcuts to eadd with fixed operations. Maybe I’m overthinking it.

0reactions

michelpcommented, Aug 20, 2020

As we discussed all math operators are now A.eadd(B) with the appropriate binary operator. I’ll address the possibility of union and intersection operators in another issue.

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