Functions are provided to interpolate geo-referenced point data via Inverse Path Distance Weighting. Useful for coastal marine applications where barriers in the landscape preclude interpolation with Euclidean distances.
ipdw provides the
functionality to perform interpolation of georeferenced point data using
inverse path distance weighting. Interpolation is accomplished in two
steps. First, path distances are calculated from each georeferenced
(measurement) point to each prediction point. Path distances, which
honor barriers in the landscape, are calculated based on cell-to-cell
movement through an underlying
Raster object that represents movement
cost. These path distances are subsequently used as interpolation
weights. The two-step routine follows the order of operations described
in Suominen et al. (2010) substituting the ESRI path distance algorithm
gdistance wrapped version of the
The ipdw package was developed with coastal marine applications in mind where path distances (as the fish swims) rather than Euclidean (as the crow flies) distances more accurately represent spatial connectivity. Interpolation of sparse grids in coastal areas otherwise end up bleeding through land areas.
install.packages('devtools') # package devtools neededdevtools::install_github("jsta/ipdw")
Joseph Stachelek and Christopher J. Madden (2015). Application of Inverse Path Distance weighting for high density spatial mapping of coastal water quality patterns. International Journal of Geographical Information Science preprint | journal
Tapio Suominen, Harri Tolvanen, and Risto Kalliola (2010). Surface layer salinity gradients and flow patterns in the archipelago coast of SW Finland, northern Baltic Sea. Marine Environmental Research journal
costRasterGenoutput resolution (#8)
NEWS.mdfile to track changes to the package.