| akima | Wave distortions data. |
| sps_eval | Evaluates spline on given points |
| sps_fun | Shape Preserving Bi-variate and Uni-variate Interpolation. |
| sps_interpolate | Shape Preserving Bi-variate and Uni-variate Interpolation. |
| sps_prep | Prepare list of objects for shape preserving interpolation. |