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Computing the sign of a complex number #545
Description
Originally discussed in #153 (comment).
In order to add complex support to sign, we need to agree on the definition for complex numbers.
NumPy uses sqrt(z^2)/z while an arguably more common convention is x/|x|.
For paths forward we have 3 options:
- Use NumPy's definition.
- Use the more common convention used elsewhere (MATLAB, Julia, etc).
- Not support complex numbers in
sign.
Questions
- If we choose (2), given NumPy's potential v2 release, would NumPy be willing to introduce this breaking change?
Activity
rgommers commentedon Dec 2, 2022
As discussed in a couple of places, the
z/|z|definition seems clearly better and preferred, also for numpy. Not sure of a timeline for introducing that (breaking changes are always tricky), but I think in this case it's not like they're two equal alternatives. In the standard I think we should go withz/|z|; numpy may not be compliant on that point for a while.