Legends for Maps.
maplegend
Create legends for maps and other graphics. Thematic maps need to be accompanied by legible legends to be fully comprehensible. This package offers a wide range of legends useful for cartography, some of which may also be useful for other types of graphics.
Installation
You can install the released version of maplegend
from CRAN with:
install.packages("maplegend")
Alternatively, you can install the development version of maplegend
from GitHub (dev branch) with:
remotes::install_github("riatelab/maplegend", ref = "dev")
Example
The main function is leg()
. Its type
argument defines the legend type.
library(maplegend)
opar <- par(mar = c(1,1,1,1), mfrow = c(1,2))
plot.new()
plot.window(xlim = c(0, 1), ylim = c(0, 1), asp = 1)
leg(type = "prop", val = c(10, 50, 100), pos = "topleft")
leg(type = "choro", val = c(10, 20, 30, 40, 50), pos = "bottomleft")
leg(type = "typo", val = c("A", "B", "C"), pos = "top")
leg(type = "symb", val = c("A", "B", "C"), pos = "topright")
leg(type = "prop_line", val = c(5, 50, 100), pos = "bottom", lwd = 20)
leg(type = "grad_line", val = c(1, 4, 10, 15), pos = "bottomright", lwd = c(1, 5, 10))
box()
plot.new()
plot.window(xlim = c(0, 100), ylim = c(-50,50), asp = 1)
leg(type = "prop", val = c(10, 50, 100), pos = "topleft", horiz = TRUE)
leg(type = "choro", val = c(10, 20, 30, 40, 50), pos = "left", horiz = TRUE)
leg(type = "cont", val = c(10, 20, 30, 40, 50), pos = "bottomleft", horiz = TRUE)
leg(type = "cont", val = c(10, 20, 30, 40, 50), pos = c(75, 25), horiz = FALSE)
box()
It is possible to create composed legends with leg_comp()
and leg_draw()
.
opar <- par(mar = c(1,1,1,1))
plot.new()
plot.window(xlim = c(0, 1), ylim = c(0, 1), asp = 1)
leg_comp(type = "prop", val = c(10, 50, 100)) |>
leg_comp(type = "typo", val = c("A", "B", "C")) |>
leg_draw(pos = "top", bg = "lightblue", fg = "darkblue", frame_border = NA)
box()
par(opar)
Background
This package is primarily intended as a backend for the construction of legends in the mapsf
package. However, it can also be used independently from mapsf
with base
plots or even with igraph
plots.
Community Guidelines
One can contribute to the package through pull requests and report issues or ask questions here.
This project uses conventional commits and semantic versioning.