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Rasterize shapefile

Source: R/shp2rast.R
shp2rast.Rd

The function will rasterize the shapefile using the parameters of y, a SpatRaster. When the argument y is provided, the resolution parameter is ignored. When the argument ymask is TRUE, y is used as a mask for x.

Usage

shp2rast(
  x,
  y = NULL,
  sps.col,
  ymask = FALSE,
  background = NA,
  touches = TRUE,
  resolution,
  values = 1,
  filename = NULL,
  ...
)

Arguments

x

SpatVector or a two-column matrix (point coordinates)

y

SpatRaster

sps.col

character. It should be a variable name in x.

ymask

logical. If TRUE, y will be used as a mask for x.

background

numeric. Value to put in the cells that are not covered by any of the features of x. Default is NA

touches

logical. If TRUE, all cells touched by lines or polygons are affected, not just those on the line render path, or whose center point is within the polygon. If touches=TRUE, add cannot be TRUE

resolution

numeric vector of length 1 or 2 to set the spatial resolution (see res). If this argument is used, arguments ncols and nrows are ignored

values

typically a numeric vector of length 1 or nrow(x). If the length is below nrow(x) the values will be recycled to nrow(x). Only used when x is a matrix. Can also be a matrix or data.frame

filename

character. Output filename

...

additional arguments passed to fun

Value

SpatRaster

Examples

# \donttest{
library(terra)

shp <- terra::vect(system.file("extdata", "shps_iucn_spps_rosauer.shp",
                              package="phyloraster"))

# create a polygon to use as mask with an extent
e <- terra::ext(113, 123, -43.64, -33.90)
p <- terra::as.polygons(e, crs="")
coun.crop <- terra::crop(p, terra::ext(shp))
coun.rast <- terra::rasterize(coun.crop,
terra::rast(terra::ext(shp), resolution = 0.5))

plot(coun.rast, col = "green")


# rasterizing with the mask of the polygon
shp.t <- shp2rast(shp, y = coun.rast, sps.col = "BINOMIAL",
ymask = TRUE, background = 0)
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
plot(shp.t, col = c("grey", "green"))


# rasterizing without using mask
shp.t2 <- shp2rast(shp, sps.col = "BINOMIAL", ymask = FALSE,
background = NA, resolution = 0.1)
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
#> Warning: [rasterize] unexpected additional argument(s): values
plot(shp.t2[[9]], col = c("grey", "green"))

# }