Portable intrinsics for numpy (numpypi)

Warnings!

• This is not meant to be a replacement for numpy.
• These portable intrinsic functions are not efficient.
• These modules are unsafe in that they try to wrap numpy and replace certain functions so you can not readily tell where the function comes from.
• Only a subset of intrinsic functions are implemented as portable.

• Provides portable intrinsic functions that return the same bitwise floating-point values on different platforms.

Why?

• We need some way to obtain bitwise-the-same floating-point values in certain non-time-critical calculations.

How?

• Using just "+", "-", "*", and "1/" operations one can "hope" to obtain the same results on different platofrms if they adhere to recommendations in IEEE 754 (https://en.wikipedia.org/wiki/IEEE_754).
• Avoid z=a/b by using d=1/b ; z=a*d.
• Evaluate intrinsic functions using series or root-finding, rather than the c-library version of the functions.
• Retain accuracy in series by summing from smallest terms first.

Where?

• Works on Linux, Windows and Mac and for both python2 and python3.
• Regularly tested with GitHub Actions.

Test?

python test_series.py

To use

In python

import numpypi_series

or (be careful!)

import numpypi_series as numpy