pwl_approx_1d

pwl_approx_1d, an Octave code which defines and evaluates a piecewise linear function, using NC "control points", which approximates a set of ND data points (x(i),y(i)).

The test code needs access to the test_interp_1d() library.

Licensing:

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

Languages:

pwl_approx_1d is available in a C version and a C++ version and a Fortran90 version and a MATLAB version and an Octave version.

Related Data and Programs:

pwl_approx_1d_test

bernstein_polynomial, an Octave code which evaluates the Bernstein polynomials, useful for uniform approximation of functions;

pwl_interp_1d, an Octave code which interpolates a set of data using a piecewise linear function.

test_interp, an Octave code which defines a number of test problems for interpolation, provided as a set of (x,y) data.

test_interp_1d, an Octave code which defines test problems for interpolation of data y(x), depending on a 2D argument.

Reference:

1. Kendall Atkinson,
   An Introduction to Numerical Analysis,
   Prentice Hall, 1989,
   ISBN: 0471624896,
   LC: QA297.A94.1989.
2. Philip Davis,
   Interpolation and Approximation,
   Dover, 1975,
   ISBN: 0-486-62495-1,
   LC: QA221.D33
3. David Kahaner, Cleve Moler, Steven Nash,
   Numerical Methods and Software,
   Prentice Hall, 1989,
   ISBN: 0-13-627258-4,
   LC: TA345.K34.

Source Code:

• pwl_approx_1d.m, determines the control points and values to be used by a piecewise linear approximant to given data.
• pwl_approx_1d_matrix.m, evaluates a matrix used to determine the control points.
• pwl_interp_1d.m, evaluates a piecewise linear interpolant.