INTERP_TRIG
Trigonometric interpolation of evenly spaced data

INTERP_TRIG, a MATLAB library which evaluates the trigonometric interpolant to a set of evenly spaced data.

Given data at 2N+1 equally spaced points x(i), which we may assume are samples of a function f(x), the trigonometric interpolant has the form 

        q(x) = a0 + sum ( 1 <= i <= N) a(i) cos(i*x)
                  + sum ( 1 <= i <= N) b(i) sin(i*x)

Licensing:

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

Languages:

INTERP_TRIG is available in a MATLAB version.

Related Data and Programs:

DIVDIF, a MATLAB library which uses divided differences to interpolate data.

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

INTERP, a MATLAB library which can be used for parameterizing and interpolating data;

interp_trig_test

LAGRANGE_INTERP_1D, a MATLAB library which defines and evaluates the Lagrange polynomial p(x) which interpolates a set of data, so that p(x(i)) = y(i).

RBF_INTERP_1D, a MATLAB library which defines and evaluates radial basis function (RBF) interpolants to 1D data.

SHEPARD_INTERP_1D, a MATLAB library which defines and evaluates Shepard interpolants to 1D data, which are based on inverse distance weighting.

SPARSE_INTERPOLANT a MATLAB library which can be used to define a sparse interpolant to a function f(x) of a multidimensional argument.

SPLINE, a MATLAB library which computes functions that approximate or interpolate data.

TEST_APPROX, a MATLAB library which defines a number of test problems for approximation and interpolation.

TEST_INTERP, a MATLAB library which defines a number of test problems for interpolation, provided as a set of (x,y) data.

TEST_INTERP_1D, a MATLAB library which defines test problems for interpolation of data y(x), depending on a 1D argument.

VANDERMONDE_INTERP_1D, a MATLAB library which finds a polynomial interpolant to data by setting up and solving a linear system involving the Vandermonde matrix.

Source Code:

Last revised on 02 February 2019.