https://www.mathworks.com/help/curvefit/least-squares-approximation-by-natural-cubic-splines.html
Least-Squares Approximation by Natural Cubic Splines - MATLAB & Simulink
The construction of a least-squares approximant usually requires that one have in hand a basis for the space from which the data are to be approximated.
least squares approximationcubic splinesnaturalmatlabsimulink
https://docs.rs/cubic-splines/latest/cubic_splines/
cubic_splines - Rust
API documentation for the Rust `cubic_splines` crate.
cubic splinesrust