test_interp_fun, a C++ code which defines formulas for functions used to test interpolation algorithms at arbitrary arguments.
The related packages TEST_INTERP and TEST_APPROX provide discrete data sets of (x,y) pairs. However, when the convergence rate of an interpolation process is of interest, it is important to be able to sample an underlying but "unknown" function at an increasing number of points. This library provides a few functions which are known to cause problems for certain kinds of interpolation schemes.
The information on this web page is distributed under the MIT license.
test_interp_fun is available in a C version and a C++ version and a Fortran77 version and a Fortran90 version and a MATLAB version and an Octave version.
chebyshev, a C++ code which computes the Chebyshev interpolant/approximant to a given function over an interval.
divdif, a C++ code which includes many routines to construct and evaluate divided difference interpolants.
RBF_INTERP, a C++ library which defines and evaluates radial basis function (RBF) interpolants to multidimensional data.
SPLINE, a C++ library which includes many routines to construct and evaluate spline interpolants and approximants.
TEST_APPROX, a C++ library which defines test problems for approximation, provided as a set of (x,y) data.
TEST_INTERP, a C++ library which defines a number of test problems for interpolation, provided as a set of (x,y) data.