v7.3.0: regression, modulo with negative number broken

[dnalborczyk]

repro:

v7.2.0

math.bignumber(-175).modulo(100)

// -75

v7.3.0

math.bignumber(-175).modulo(100)

// 25

[ovk]

Why you consider it broken? It was actually fixed in #1964 to behave as mathematical modulo operation (consistently with how it behaves for regular number type).

-175 mod 100 is indeed 25 as you can see here.

[dnalborczyk]

interesting.

➜ node
Welcome to Node.js v14.12.0.
Type ".help" for more information.
> -175 % 100
-75
> 

[dnalborczyk]

nm, seems to be the difference between modulo and remainder: https://2ality.com/2019/08/remainder-vs-modulo.html, if that is the intend.

[josdejong]

nm, seems to be the difference between modulo and remainder: https://2ality.com/2019/08/remainder-vs-modulo.html, if that is the intend.

@dnalborczyk that is correct. In v7.3.0 we fixed/changed the behavior of modulus for BigNumbers to be consistent with how it's calculated for numbers in mathjs, and how it's calculated by the major math applications that I know of: as modulo operator like described in section "3 The modulo operator mod" of the article that you link to: https://2ality.com/2019/08/remainder-vs-modulo.html#the-modulo-operator-mod.

I hope this clarifies what's going on.

[dnalborczyk]

thank you for the clarification! @josdejong @ovk