sine_integral, a Python code which evaluates the Cosine Integral and the Sine Integral, by Shanjie Zhang, Jianming Jin;
The Fortran77 source code of this library is copyrighted by Shanjie Zhang and Jianming Jin. However, they give permission to incorporate routines from this library into a user program provided that the copyright is acknowledged.
sine_integral is available in a Fortran90 version and a Python version.
cordic, a Python code which uses the CORDIC method to compute certain elementary functions.
fn, a Python code which evaluates elementary and special functions, by Wayne Fullerton.
polpak, a Python code which evaluates certain mathematical functions, especially some recursive polynomial families.
test_values, a Python code which contains a few test values of many functions.