Precedence of % (mod) is higher than * and /

[gwhitney]

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Describe the bug
Unlike in any other language I have checked, the precedence of % (or mod) used as a binary remainder operator is higher than * and /. As it is essentially a division operation, its precedence should be the same as * and /, as it is in essentially every other language checked.

To Reproduce
Evaluate 3.6 * 28 % 25. Currently mathjs produces 10.8 = 3.6 * 3 = 3.6 * (28 % 25). It should produce 0.8 = 100.8 % 25 = (3.6 * 28) % 25, as multiplicative/division operators should be evaluated left to right.

[nkumawat34]

can i work on this issue.

[nkumawat34]

They have written in their document.
It should give priority same with multiplication and divide.

[gwhitney]

Yes, the mathjs documentation is clear on this behavior. It is just different than just about any other system. But I would not recommend working on changing it unless the designer @josdejong agrees there should be a change. He may have his reasons for the unusual behavior, which I would respect. So this issue was more of a proposal/query as to why the departure from norms. I think if the current behavior is retained, such a rationale should be added to the documentation.

[josdejong]

Thanks for bringing this up Glen. The precedence of the modulus operator regularly leads to questions and unexpected behavior. I think it would be a good thing to bring bring the behavior in line with other applications: let module have the same precedence as multiplication and division.

Originally, modulus had the same precedence as multiplcation and division. I think the precedence was accidentally changed as as unintened side effect of implementing support for using % as percentage in #2304. See also (#3189 (comment).

It would be great if you can pick this up @nkumawat34 , though it's not the easiest first issue. Do you like a challenge? 😉

[nkumawat34]

I will pick it.

[josdejong]

Thanks

[nkumawat34]

Please review my PR #3311

[josdejong]

👍 I'll look into it this week, thanks!!