closest_point_brute, a C code which uses brute force to find the nearest of a set of N points in D dimensions to a given test point. This is sometimes called a nearest neighbor calculation.
The information on this web page is distributed under the MIT license.
closest_point_brute is available in a C version and a C++ version and a Fortran77 version and a Fortran90 version and a MATLAB version and an Octave version and a Python version.
closest_pair_brute, a C code which uses brute force to solve a 2D version of the closest pair problem, which identifies the closest pair of points in a given collection.
nearest_interp_1d, a C code which interpolates a set of data using a piecewise constant interpolant defined by the nearest neighbor criterion.