Find pits (depressions with no outlet)
pitfinder.Rdfind pits (depressions with no outlet) using a flow direction raster, to support the delineation of catchments.
Arguments
- x
SpatRaster with flow-direcion. See
flowDir- pits_on_boundary
logical if
TRUE(default) pits are considered also on the boundary. IfFALSEpits are considered only within the terrain domain.- filename
character. Output filename
- ...
additional arguments for writing files as in
writeRaster
Examples
## example elevation data
elev <- array(NA,c(9,9))
dx <- 1
dy <- 1
for (r in 1:nrow(elev)) {
x <- (r-5)*dx
for (c in 1:ncol(elev)) {
y <- (c-5)*dy
elev[r,c] <- 10+5*(x^2+y^2)
}
}
elev <- cbind(elev,elev,elev,elev)
elev <- rbind(elev,elev,elev,elev)
elev <- rast(elev)
## Flow Directions
flowdir<- terrain(elev,v="flowdir")
t(array(flowdir[],rev(dim(flowdir)[1:2])))
#> [,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9] [,10] [,11] [,12] [,13]
#> [1,] 2 2 2 4 4 4 8 8 8 2 2 2 4
#> [2,] 2 2 2 4 4 4 8 8 8 2 2 2 4
#> [3,] 2 2 2 4 4 4 8 8 8 2 2 2 4
#> [4,] 1 1 1 2 4 8 16 16 16 1 1 1 2
#> [5,] 1 1 1 1 0 16 16 16 16 1 1 1 1
#> [6,] 1 1 1 128 64 32 16 16 16 1 1 1 128
#> [7,] 128 128 128 64 64 64 32 32 32 128 128 128 64
#> [8,] 128 128 128 64 64 64 32 32 32 128 128 128 64
#> [9,] 128 128 128 64 64 64 32 32 32 128 128 128 64
#> [10,] 2 2 2 4 4 4 8 8 8 2 2 2 4
#> [11,] 2 2 2 4 4 4 8 8 8 2 2 2 4
#> [12,] 2 2 2 4 4 4 8 8 8 2 2 2 4
#> [13,] 1 1 1 2 4 8 16 16 16 1 1 1 2
#> [14,] 1 1 1 1 0 16 16 16 16 1 1 1 1
#> [15,] 1 1 1 128 64 32 16 16 16 1 1 1 128
#> [16,] 128 128 128 64 64 64 32 32 32 128 128 128 64
#> [17,] 128 128 128 64 64 64 32 32 32 128 128 128 64
#> [18,] 128 128 128 64 64 64 32 32 32 128 128 128 64
#> [19,] 2 2 2 4 4 4 8 8 8 2 2 2 4
#> [20,] 2 2 2 4 4 4 8 8 8 2 2 2 4
#> [21,] 2 2 2 4 4 4 8 8 8 2 2 2 4
#> [22,] 1 1 1 2 4 8 16 16 16 1 1 1 2
#> [23,] 1 1 1 1 0 16 16 16 16 1 1 1 1
#> [24,] 1 1 1 128 64 32 16 16 16 1 1 1 128
#> [25,] 128 128 128 64 64 64 32 32 32 128 128 128 64
#> [26,] 128 128 128 64 64 64 32 32 32 128 128 128 64
#> [27,] 128 128 128 64 64 64 32 32 32 128 128 128 64
#> [28,] 2 2 2 4 4 4 8 8 8 2 2 2 4
#> [29,] 2 2 2 4 4 4 8 8 8 2 2 2 4
#> [30,] 2 2 2 4 4 4 8 8 8 2 2 2 4
#> [31,] 1 1 1 2 4 8 16 16 16 1 1 1 2
#> [32,] 1 1 1 1 0 16 16 16 16 1 1 1 1
#> [33,] 1 1 1 128 64 32 16 16 16 1 1 1 128
#> [34,] 128 128 128 64 64 64 32 32 32 128 128 128 64
#> [35,] 128 128 128 64 64 64 32 32 32 128 128 128 64
#> [36,] 128 128 128 64 64 64 32 32 32 128 128 128 64
#> [,14] [,15] [,16] [,17] [,18] [,19] [,20] [,21] [,22] [,23] [,24] [,25]
#> [1,] 4 4 8 8 8 2 2 2 4 4 4 8
#> [2,] 4 4 8 8 8 2 2 2 4 4 4 8
#> [3,] 4 4 8 8 8 2 2 2 4 4 4 8
#> [4,] 4 8 16 16 16 1 1 1 2 4 8 16
#> [5,] 0 16 16 16 16 1 1 1 1 0 16 16
#> [6,] 64 32 16 16 16 1 1 1 128 64 32 16
#> [7,] 64 64 32 32 32 128 128 128 64 64 64 32
#> [8,] 64 64 32 32 32 128 128 128 64 64 64 32
#> [9,] 64 64 32 32 32 128 128 128 64 64 64 32
#> [10,] 4 4 8 8 8 2 2 2 4 4 4 8
#> [11,] 4 4 8 8 8 2 2 2 4 4 4 8
#> [12,] 4 4 8 8 8 2 2 2 4 4 4 8
#> [13,] 4 8 16 16 16 1 1 1 2 4 8 16
#> [14,] 0 16 16 16 16 1 1 1 1 0 16 16
#> [15,] 64 32 16 16 16 1 1 1 128 64 32 16
#> [16,] 64 64 32 32 32 128 128 128 64 64 64 32
#> [17,] 64 64 32 32 32 128 128 128 64 64 64 32
#> [18,] 64 64 32 32 32 128 128 128 64 64 64 32
#> [19,] 4 4 8 8 8 2 2 2 4 4 4 8
#> [20,] 4 4 8 8 8 2 2 2 4 4 4 8
#> [21,] 4 4 8 8 8 2 2 2 4 4 4 8
#> [22,] 4 8 16 16 16 1 1 1 2 4 8 16
#> [23,] 0 16 16 16 16 1 1 1 1 0 16 16
#> [24,] 64 32 16 16 16 1 1 1 128 64 32 16
#> [25,] 64 64 32 32 32 128 128 128 64 64 64 32
#> [26,] 64 64 32 32 32 128 128 128 64 64 64 32
#> [27,] 64 64 32 32 32 128 128 128 64 64 64 32
#> [28,] 4 4 8 8 8 2 2 2 4 4 4 8
#> [29,] 4 4 8 8 8 2 2 2 4 4 4 8
#> [30,] 4 4 8 8 8 2 2 2 4 4 4 8
#> [31,] 4 8 16 16 16 1 1 1 2 4 8 16
#> [32,] 0 16 16 16 16 1 1 1 1 0 16 16
#> [33,] 64 32 16 16 16 1 1 1 128 64 32 16
#> [34,] 64 64 32 32 32 128 128 128 64 64 64 32
#> [35,] 64 64 32 32 32 128 128 128 64 64 64 32
#> [36,] 64 64 32 32 32 128 128 128 64 64 64 32
#> [,26] [,27] [,28] [,29] [,30] [,31] [,32] [,33] [,34] [,35] [,36]
#> [1,] 8 8 2 2 2 4 4 4 8 8 8
#> [2,] 8 8 2 2 2 4 4 4 8 8 8
#> [3,] 8 8 2 2 2 4 4 4 8 8 8
#> [4,] 16 16 1 1 1 2 4 8 16 16 16
#> [5,] 16 16 1 1 1 1 0 16 16 16 16
#> [6,] 16 16 1 1 1 128 64 32 16 16 16
#> [7,] 32 32 128 128 128 64 64 64 32 32 32
#> [8,] 32 32 128 128 128 64 64 64 32 32 32
#> [9,] 32 32 128 128 128 64 64 64 32 32 32
#> [10,] 8 8 2 2 2 4 4 4 8 8 8
#> [11,] 8 8 2 2 2 4 4 4 8 8 8
#> [12,] 8 8 2 2 2 4 4 4 8 8 8
#> [13,] 16 16 1 1 1 2 4 8 16 16 16
#> [14,] 16 16 1 1 1 1 0 16 16 16 16
#> [15,] 16 16 1 1 1 128 64 32 16 16 16
#> [16,] 32 32 128 128 128 64 64 64 32 32 32
#> [17,] 32 32 128 128 128 64 64 64 32 32 32
#> [18,] 32 32 128 128 128 64 64 64 32 32 32
#> [19,] 8 8 2 2 2 4 4 4 8 8 8
#> [20,] 8 8 2 2 2 4 4 4 8 8 8
#> [21,] 8 8 2 2 2 4 4 4 8 8 8
#> [22,] 16 16 1 1 1 2 4 8 16 16 16
#> [23,] 16 16 1 1 1 1 0 16 16 16 16
#> [24,] 16 16 1 1 1 128 64 32 16 16 16
#> [25,] 32 32 128 128 128 64 64 64 32 32 32
#> [26,] 32 32 128 128 128 64 64 64 32 32 32
#> [27,] 32 32 128 128 128 64 64 64 32 32 32
#> [28,] 8 8 2 2 2 4 4 4 8 8 8
#> [29,] 8 8 2 2 2 4 4 4 8 8 8
#> [30,] 8 8 2 2 2 4 4 4 8 8 8
#> [31,] 16 16 1 1 1 2 4 8 16 16 16
#> [32,] 16 16 1 1 1 1 0 16 16 16 16
#> [33,] 16 16 1 1 1 128 64 32 16 16 16
#> [34,] 32 32 128 128 128 64 64 64 32 32 32
#> [35,] 32 32 128 128 128 64 64 64 32 32 32
#> [36,] 32 32 128 128 128 64 64 64 32 32 32
## detect pits
pits <- pitfinder(flowdir)
## Application with example DEM
elev <- rast(system.file('ex/elev.tif',package="terra"))
flowdir <- terrain(elev, "flowdir")
pits <- pitfinder(flowdir)
pits2 <- pitfinder(flowdir, pits_on_boundary=FALSE)
plot((pits>0)==(pits2>0))
