toms446, a FORTRAN90 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: or NETLIB:


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.

Related Data and Programs:

BERNSTEIN_POLYNOMIAL, a FORTRAN90 code which evaluates the Bernstein polynomials, useful for uniform approximation of functions;

CHEBYSHEV, a FORTRAN90 code which computes the Chebyshev interpolant/approximant to a given function over an interval.

CHEBYSHEV_SERIES, a FORTRAN90 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, a FORTRAN90 code which computes interpolants by divided differences.

HERMITE, a FORTRAN90 code which computes the Hermite interpolant, a polynomial that matches function values and derivatives.

PPPACK, a FORTRAN90 code which computes piecewise polynomial functions, including cubic splines.

SPLINE, a FORTRAN90 code which can construct and evaluate spline interpolants and approximants.

TEST_APPROX, a FORTRAN90 code which defines test functions for approximation and interpolation.



Original FORTRAN77 version by Roger Broucke; FORTRAN90 version by John Burkardt.


  1. Roger Broucke,
    Algorithm 446: Ten Subroutines for the Manipulation of Chebyshev Series,
    Communications of the ACM,
    October 1973, Volume 16, Number 4, pages 254-256.

Source Code:

Last revised on 13 March 2021.