Grass_Raster_SurfaceInterpolationService - This service could be used for raster data interpolation. Elevation surface generation from a contour map, and two IDW (Inverse Distance Weighted) surface interpolation of raster data are available.
When changing resolution of rasters that represent continuous fields, interpolation should be used. Interpolation
is also needed when filling gaps in merged raster data or when raster data are patchy and contain NULL values that
need to be replaced to achieve continuous coverage.[Markus Neteler, Helena Mitasova, 2004].
Operations:
surf_contour - Creates a raster elevation map from a rasterized contour map surf_idw - Fills a grid cell (raster) matrix with interpolated values generated from a set of input layer data points. It uses a numerical approximation technique based on distance squared weighting of the values of nearest data points. The number of nearest data points used to determined the interpolated value of a cell can be specified by the user (default: 12 nearest data points). surf_idw2 - Fills a raster matrix with interpolated values generated from a set of irregularly spaced data points using numerical approximation (weighted averaging) techniques. The interpolated value of a cell is determined by values of nearby data points and the distance of the cell from those input points.
