AUTO is a publicly available software for continuation and bifurcation problems in ordinary differential equations originally written in 1980 and widely used in the dynamical systems community.

Boost.Multiprecision

A Package for Automatic Differentiation of Algorithms Written in C/C++

C++ wrappers for SIMD intrinsics and parallelized, optimized mathematical functions (SSE, AVX, AVX512, NEON, SVE))

Python Imaging Library (Fork)

Boost.org math module

A computer algebra system written in pure Python

matplotlib: plotting with Python

Manipulation and analysis of geometric objects

A parser generator for visibly pushdown languages.

The pytest framework makes it easy to write small tests, yet scales to support complex functional testing

Python library for arbitrary-precision floating-point arithmetic