test_interp_nd, a C code which provides test functions for multidimensional interpolation.
All the functions are defined over the unit hypercube [0,1]^M, for arbitrary spatial dimension M. They include:
For each function, methods are provided to evaluate:
Most of the functions include a shift vector w whose entries can be chosen randomly in the unit hypercube, and a coefficient vector c whose entries should be positive, and for which the integration problem becomes harder as the sum of the entries increases.
The code requires access to the R8LIB library.
The computer code and data files described and made available on this web page are distributed under the MIT license
test_interp_nd is available in a C version and a C++ version and a FORTRAN90 version and a MATLAB version.
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