ccl_test

ccl_test a MATLAB code which calls ccl(), which estimates the Lebesgue constants for sets of points in [-1,+1] computed in several ways. The program is probably of limited interest except as an example of an application of the lebesgue_constant() function.

Licensing:

The information on this web page is distributed under the MIT license.

Languages:

ccl_test is available in a MATLAB version and an Octave version.

Related Data and Programs:

lebesgue, a MATLAB code which is given nodes in 1D, plots the Lebesgue function, and estimates the Lebesgue constant, which measures the maximum magnitude of the potential error of Lagrange polynomial interpolation.

Source Code:

ccl_test.m, calls all the tests.
ccl_test.sh, runs all the tests.
ccl_test.txt, the output file.

chebyzero_test.m, evaluates the Lebesgue constants for Chebyshev Zero nodes.
cvt_chebyshev_test.m, evaluates the Lebesgue constants for CVT points initialized as Chebyshev Zero nodes.
cvt_random_test.m, evaluates the Lebesgue constants for CVT points initialized as random values.
cvt_uniform_test.m, evaluates the Lebesgue constants for CVT points initialized as uniform values.
lebesgue_constant.m, estimates the Lebesgue constant.
lebesgue_constant_test.m, tests lebesgue_constant() on a simple case.
lebesgue_function.m, evaluates the Lebesgue function.
r8vec2_print.m, prints a pair of R8VEC's.
timestamp.m, prints the current YMDHMS date as a timestamp;

Data Files:

Last revised on 19 December 2025.