terra (version 1.8-10)

direction: Direction

Description

The direction (azimuth) to or from the nearest cell that is not NA. The direction is expressed in radians, unless you use argument degrees=TRUE.

Usage

# S4 method for SpatRaster
direction(x, from=FALSE, degrees=FALSE, method="cosine", filename="", ...)

Value

SpatRaster

Arguments

x

SpatRaster

from

Logical. Default is FALSE. If TRUE, the direction from (instead of to) the nearest cell that is not NA is returned

degrees

Logical. If FALSE (the default) the unit of direction is radians.

method

character. Should be "geo", or "cosine". With "geo" the most precise but slower geodesic method of Karney (2003) is used. The "cosine" method is faster but less precise

filename

Character. Output filename (optional)

...

Additional arguments as for writeRaster

See Also

distance

Examples

r <- rast(ncol=36,nrow=18, crs="+proj=merc")
values(r) <- NA
r[306] <- 1
b <- direction(r, degrees=TRUE) 
plot(b)

crs(r) <- "+proj=longlat"
b <- direction(r) 
plot(b)