Get raster values at specific river locations

Get values from a raster at specific locations in a river network. It can be used to extract relevant values from upstream-averaged rasters as produced by rast_riverweight.

Usage

get_riverweight(x, rst, river, args_locate_site = list())

Arguments

x

Coordinate(s) of the location(s) of interest. These can be expressed as a 2-valued vector (indicating longitudinal and latitudinal coordinate of the single point of interest–in the same coordinate system as rst and river), a matrix or data frame (with two columns, for longitudinal and latitudinal coordinates, respectively, and as many rows as the number of points of interest). See examples.

rst

A SpatRaster object as obtained by rast_riverweight.

river

A river object generated via aggregate_river.

args_locate_site

List of arguments to be passed to locate_site. See examples.

Value

A data frame with columns named after the layers of rst, and as many rows as the number of rows in x.

See also

rast_riverweight, locate_site

Examples

data(wigger)

r1 <- terra::rast(system.file("extdata/landcover.tif", package = "rivnet")) 
# legend: 1-urban; 2-agriculture; 3-forest; 4-improductive

r.exp <- rast_riverweight(r1, wigger)

v1 <- get_riverweight(c(641000, 226100), r.exp, wigger) # from vector
m <- matrix(c(641000, 226100), 1, 2)
v2 <- get_riverweight(m, r.exp, wigger) # from matrix
df <- data.frame(m)
v3 <- get_riverweight(df, r.exp, wigger) # from data frame

m2 <- matrix(c(641000, 226100, 639600, 226100), 2, 2, byrow = TRUE)
v4 <- get_riverweight(m2, r.exp , wigger) # from matrix multipoint

# \donttest{
# use showPlot = TRUE from locate_site to check snapping of point to the river network
v1 <- get_riverweight(c(641000, 226100), r.exp, wigger, 
          args_locate_site = list(showPlot = TRUE)) 

# }