system) Inverse distance weighting Kriging Gradient-enhanced kriging (GEK) Thin plate spline Polyharmonic spline (the thin-plate-spline is a special case of a polyharmonic spline) Radial basis function (Polyharmonic splines are a special case of radial basis functions with low degree polynomial terms) Least-squares spline Natural neighbour interpolation Gridding is the process of converting irregularly spaced data to a regular grid (gridded data). See also Smoothing Surface fitting Notes External links Example C++ code for several 1D, 2D and 3D spline interpolations (including Catmull-Rom splines). Multi-dimensional Hermite Interpolation and Approximation, Prof. Chandrajit Bajaja, Purdue University Python library containing 3D and 4D spline interpolation methods. Interpolation