rbf_interp_nd, a MATLAB code which defines and evaluates radial basis function (RBF) interpolants to multidimensional data.
A radial basis interpolant is a useful, but expensive, technique for definining a smooth function which interpolates a set of function values specified at an arbitrary set of data points.
Given nd multidimensional points xd with function values fd, and a basis function phi(r), the form of the interpolant is
f(x) = sum ( 1 <= i <= nd ) w(i) * phi(||x-xd(i)||)where the weights w have been precomputed by solving
sum ( 1 <= i <= nd ) w(i) * phi(||xd(j)-xd(i)||) = fd(j)
Four families of radial basis functions are provided.
RBF_INTERP_ND needs access to the R8LIB library.
The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.
rbf_interp_nd is available in a C version and a C++ version and a FORTRAN90 version and a MATLAB version.
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