Maybe something like this: https://numerics.mathdotnet.com?
NOTE: The number of mentions on this list indicates mentions on common posts plus user suggested alternatives. Hence, a higher number means a more popular project.
Found this in a project I am currently working. Does someone knows the reason to implement it this way?
1 project | reddit.com/r/csharp | 21 Jul 2021
V1.2 of Vim.Math3d C# Library
1 project | news.ycombinator.com | 8 Sep 2021
GitHub - vimaec/Math3D: A portable and feature rich 3D math library for C# that can replace System.Numerics
1 project | reddit.com/r/programming | 8 Sep 2021
EU iLVL disparity of approx. 150k players with 100+ games played
2 projects | reddit.com/r/worldofpvp | 15 Mar 2021
Modules in Swift Playgrounds
1 project | reddit.com/r/swift | 14 May 2022