toms446, an Octave code which implements ACM TOMS algorithm 446, for the manipulation of Chebyshev series, by Roger Broucke.
The text of many ACM TOMS algorithms is available online through ACM: https://calgo.acm.org/ or NETLIB: https://www.netlib.org/toms/index.html.
The computer code and data files described and made available on this web page are distributed under the MIT license
toms446 is available in a C version and a C++ version and a Fortran90 version and a MATLAB version and an Octave version.
bernstein_polynomial, an Octave code which evaluates the Bernstein polynomials, useful for uniform approximation of functions;
chebyshev, an Octave code which computes the Chebyshev interpolant/approximant to a given function over an interval.
chebyshev_series, an Octave code which can evaluate a Chebyshev series approximating a function f(x), while efficiently computing one, two or three derivatives of the series, which approximate f'(x), f''(x), and f'''(x), by Manfred Zimmer.
divdif, an Octave code which computes interpolants by divided differences.
hermite_polynomial, an Octave code which computes the Hermite interpolant, a polynomial that matches function values and derivatives.
spline, an Octave code which can construct and evaluate spline interpolants and approximants.
test_approx, an Octave code which defines test functions for approximation and interpolation.
Original FORTRAN77 version by Roger Broucke; This version by John Burkardt.