# Interpolate points using a moving window

`interpIDW.Rd`

Interpolate points within a moving window using inverse distance weighting. The maximum number of points used can be restricted, optionally by selecting the nearest points.

## Usage

```
# S4 method for SpatRaster,SpatVector
interpIDW(x, y, field, radius, power=2, smooth=0,
maxPoints=Inf, minPoints=1, near=TRUE, fill=NA, filename="", ...)
# S4 method for SpatRaster,matrix
interpIDW(x, y, radius, power=2, smooth=0,
maxPoints=Inf, minPoints=1, near=TRUE, fill=NA, filename="", ...)
```

## Arguments

- x
SpatRaster

- y
SpatVector or matrix with three columns (x,y,z)

- field
character. field name in SpatVector

`y`

- radius
numeric. The radius of the circle (single number). If

`near=FALSE`

, it is also possible to use two or three numbers. Two numbers are interpreted as the radii of an ellipse (x and y-axis). A third number should indicated the desired, counter clockwise, rotation of the ellipse (in degrees)- power
numeric. Weighting power

- smooth
numeric. Smoothing parameter

- minPoints
numeric. The minimum number of points to use. If fewer points are found in a search ellipse it is considered empty and the fill value is returned

- maxPoints
numeric. The maximum number of points to consider in a search area. Additional points are ignored. If fewer points are found, the fill value is returned

- near
logical. Should the nearest points within the neighborhood be used if

`maxPoints`

is reached?- fill
numeric. value to use to fill empty cells

- filename
character. Output filename

- ...
additional arguments for writing files as in

`writeRaster`