idw.dist: Inverse distance calculation using custom distances
In statnmap/GeoDist: Constrained distance calculation and associated geotools

Inverse distance calculation using custom distances

idw.dist(
  data,
  coords,
  locations,
  loc.dist,
  idp = 2,
  max.dist,
  nmin = 1,
  nmax,
  longlat = TRUE
)

`data`	vector of values to be interpolated at data coordinates
`coords`	coordinates of observation points. Can also be an object of class SpatialPoints*. Not necessary with loc.dist.
`locations`	coordinates of points where to provide predictions. Can also be an object of class SpatialPoints*. Not necessary with loc.dist.
`loc.dist`	Matrix of distances between data (rows) and locations (cols)
`idp`	specify the inverse distance weighting power. Default to 2.
`max.dist`	Maximum distance radius for neighbours search in the idw interpolation. maxdist is in km when longlat is TRUE (non-projected crs), in meters otherwise. If loc.dist is specified, maxdist should be in same distance unit.
`nmin`	if the number of nearest observations within distance maxdist is less than nmin, a missing value will be generated; see maxdist
`nmax`	the number of nearest observations that should be used for a kriging prediction or simulation, where nearest is defined in terms of the space of the spatial locations. By default, all observations are used
`longlat`	Logical Wether coordinates are not-projected (TRUE) or are projected (FALSE).