pchip_test, a FORTRAN77 code which calls pchip(), which constructs a piecewise cubic Hermite interpolant to data, and carry out various related operations, by Fred Fritsch.
The computer code and data files made available on this web page are distributed under the GNU LGPL license.
pchip, a FORTRAN77 code which can construct a piecewise cubic Hermite interpolant to data, and carry out various related operations, by Fred Fritsch.
TEST02 generates some files that can be input to GNUPLOT to illustrate the problem of interpolating monotonic data with a piecewise cubic Hermite spline.
TEST03 generates some files that can be input to GNUPLOT to illustrate the problem of interpolating monotonic data with a cubic spline.