pppack_test a FORTRAN77 code which calls pppack(), which carries out interpolation and approximation using piecewise polynomials, especially cubic splines, by Carl de Boor.
The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.
pppack, a FORTRAN77 code which carries out interpolation and approximation using piecewise polynomials, especially cubic splines, by Carl de Boor.