getLinkLayer {cartography}

Create a Links Layer from a Data Frame of Links.

Description

Create a links layer from a data frame of links.

Usage

getLinkLayer(x, xid = NULL, df, dfid = NULL)

Arguments

x

an sf object, a simple feature collection (or a Spatial*DataFrame).

xid

name of the identifier variable in x, default to the first column (optional)

df

a data frame that contains identifiers of starting and ending points.

dfid

names of the identifier variables in df, character vector of length 2, default to the two first columns. (optional)

Value

An sf LINESTRING is returned, it contains two variables (origins and destinations).

See Also

gradLinkLayer, propLinkLayer

Examples

library(sf)
mtq <- st_read(system.file("gpkg/mtq.gpkg", package="cartography"))
mob <- read.csv(system.file("csv/mob.csv", package="cartography"))
# Select links from Fort-de-France (97209))
mob_97209 <- mob[mob$i == 97209, ]
# Create a link layer
mob.sf <- getLinkLayer(x = mtq, df = mob_97209, dfid = c("i", "j"))
# Plot the links1
plot(st_geometry(mtq), col = "grey")
plot(st_geometry(mob.sf), col = "red4", lwd = 2, add = TRUE)