Consider making a module rather than a fork about numpy-posit

[xman]

Hi Robert,

Thanks for your feedback. Didn't see the feedback until now.

I was initially started with building posit as numpy extension. I was able to get the basic stuffs working, but the ufunc type resolving and other issues that I have forgotten now didn't work the same for native dtype and extended dtype through dtype registration API. The functions that are defined through PyNumberMethods are working well. But there are a whole list of ufunc in the numpy/core/code_generators/generate_umath.py that I didn't manage to get them work with non-standard dtype. The PyUFunc_FromFuncAndData didn't allow me to define for non-standard dtypes.

As we currently use floating as the number category for posits, it does create some confusions on the coercion e.g. posit32 and float32 are same byte size, the current numpy type system thinks posit32 (with 4 bytes and also floating category) is the same as float32, hence mess up in the type resolving.

I'll check out the numpy-quaternion to see if there are something I missed. I do hope the posit can be integrated as extension as that will avoid whole lot of other problems that you described. I'm aware of the pypi issue that the dependencies will mess up.

Once we have a consensus on the best method to merge into upstream, I'll like to update and do that merging as an optional numpy feature.

In summary, my previous main issues with building posit as numpy extension were on getting the whole list of ufunc to work seamlessly with new posit dtype, and the type coercion needs to work correctly.

Thanks again for your feedback.

Regards,
Shin Yee