Legend for Proportional Circles Maps

Plot legend for proportional circles maps

legendCirclesSymbols(
  pos = "topleft",
  title.txt = "Title of the legend",
  title.cex = 0.8,
  cex = 1,
  border = "black",
  lwd = 1,
  values.cex = 0.6,
  var,
  inches,
  col = "#E84923",
  frame = FALSE,
  values.rnd = 0,
  style = "c"
)

Arguments

pos

position of the legend, one of "topleft", "top", "topright", "right", "bottomright", "bottom", "bottomleft", "bottomleftextra", "left" or a vector of two coordinates in map units (c(x, y)).

title.txt

title of the legend.

title.cex

size of the legend title.

cex

size of the legend. 2 means two times bigger.

border

color of the borders.

lwd

width of the borders.

values.cex

size of the values in the legend.

var

vector of values (at least min and max).

inches

radii of the biggest circle.

col

color of symbols.

frame

whether to add a frame to the legend (TRUE) or not (FALSE).

values.rnd

number of decimal places of the values in the legend.

style

either "c" or "e". The legend has two display styles, "c" stands for compact and "e" for extended.

Examples

library(sf)
mtq <- st_read(system.file("gpkg/mtq.gpkg", package="cartography"))
#> Reading layer `mtq' from data source 
#>   `/tmp/RtmpmpfIrO/temp_libpath18ee15f22a9e/cartography/gpkg/mtq.gpkg' 
#>   using driver `GPKG'
#> Simple feature collection with 34 features and 7 fields
#> Geometry type: MULTIPOLYGON
#> Dimension:     XY
#> Bounding box:  xmin: 690574 ymin: 1592536 xmax: 735940.2 ymax: 1645660
#> Projected CRS: WGS 84 / UTM zone 20N
plot(st_geometry(mtq))
box()

propSymbolsLayer(x = mtq, var = "POP",
                 inches = 0.2, legend.pos = "n")

legendCirclesSymbols(pos = "topleft", inches = 0.2,
                     var = c(min(mtq$POP), max(mtq$POP)))
legendCirclesSymbols(pos = "left",
                     var = c(min(mtq$POP), max(mtq$POP)),
                     inches = 0.2, style = "e")
legendCirclesSymbols(pos = "bottomleft",
                     var = c(600, 12000, 40000, max(mtq$POP)),
                     inches = 0.2, style = "c")
legendCirclesSymbols(pos = "topright", cex = 2,
                     var = c(600, 30000,max(mtq$POP)),
                     inches = 0.2, style = "e", frame = TRUE)
legendCirclesSymbols(pos = c(736164.4, 1596658),
                     var = c(min(mtq$POP),max(mtq$POP)),
                     inches = 0.2, frame = TRUE)