SEAM 1D cubic spline interpolation and adjoint interpolation. Based on TRIP Fortran code written by Ann Campbell as an undergraduate summer project in 1991. See source code for original documentation.
The cubic interpolation routine implements a perfectly ordinary spline algorithm from Forsythe, Malcolm, and Moler's book. This package's main claim to fame is the adjoint interpolation implementation; I have no idea where else you can find such a thing.
WWS, July 08
1.4.7