# nearest_interp_1d

nearest_interp_1d, a Python code which interpolates a set of data using a piecewise constant interpolant defined by the nearest neighbor criterion.

### Languages:

nearest_interp_1d is available in a C version and a C++ version and a FORTRAN90 version and a MATLAB version and a Python version.

### Related Data and Programs:

barycentric_interp_1d, a python code which defines and evaluates the barycentric lagrange polynomial p(x) which interpolates a set of data, so that p(x(i)) = y(i). the barycentric approach means that very high degree polynomials can safely be used.

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### Source Code:

nearest_interp_1d_test01() plots a piecewise linear interpolant to the original data, and the nearest neighbor interpolant.

• p01_pwl.png, a plot of the data and piecewise linear interpolant for problem p01;
• p01_near.png, a plot of the nearest neighbor interpolant for problem p01;
• p02_pwl.png, a plot of the data and piecewise linear interpolant for problem p02;
• p02_near.png, a plot of the nearest neighbor interpolant for problem p02;
• p03_pwl.png, a plot of the data and piecewise linear interpolant for problem p03;
• p03_near.png, a plot of the nearest neighbor interpolant for problem p03;
• p04_pwl.png, a plot of the data and piecewise linear interpolant for problem p04;
• p04_near.png, a plot of the nearest neighbor interpolant for problem p04;
• p05_pwl.png, a plot of the data and piecewise linear interpolant for problem p05;
• p05_near.png, a plot of the nearest neighbor interpolant for problem p05;
• p06_pwl.png, a plot of the data and piecewise linear interpolant for problem p06;
• p06_near.png, a plot of the nearest neighbor interpolant for problem p06;
• p07_pwl.png, a plot of the data and piecewise linear interpolant for problem p07;
• p07_near.png, a plot of the nearest neighbor interpolant for problem p07;
• p08_pwl.png, a plot of the data and piecewise linear interpolant for problem p08;
• p08_near.png, a plot of the nearest neighbor interpolant for problem p08;