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Plot proportional symbols with choropleth coloration

Source: R/mf_map_help.R
mf_map_prop_choro.Rd

mf_map() with prop_choro type creates symbols that are proportional to values of a first variable and colored to reflect the classification of a second variable.

This map types uses two variables and some arguments need to be set for both variables (see Details).

For polygons, centroids are used to plot proportional symbols. This map type is not available for lines.

Usage

For polygons and points:

mf_map(x, var, type = "prop_choro",
       inches = 0.3, val_max,  symbol = "circle",
       pal, rev = FALSE, breaks = "quantile", nbreaks,
       border, lwd = 0.7, col_na = "white",
       alpha, expandBB, extent, bg, add = TRUE, leg_*)

Arguments

x

object of class sf (polygons or points)

var

names of the variables to map. The first value refers to the proportional symbols, the second one to the choropleth coloration.

type

"prop_choro"

inches

size of the largest symbol in inches (radius for circles, half width for squares)

val_max

maximum value corresponding to the largest symbol or line

symbol

type of proportional symbols, either "circle" or "square"

breaks

either a numeric vector with the actual breaks, or a classification method name. The main methods are 'quantile', 'equal', 'msd', 'ckmeans' (natural breaks), 'Q6' and 'geom'. See mf_get_breaks for details.

nbreaks

number of classes

pal

a set of colors (hex codes) or a palette name. Palette names can be obtained with hcl.pals. The default palette is the pal_seq palette (see mf_theme).

rev

if pal is a palette name, whether the ordering of the colors should be reversed (TRUE) or not (FALSE)

border

border color of proportional symbols, a hex code or color name given by colors. The default color is the background color (see mf_theme).

lwd

border width of proportional symbols

col_na

color for missing values, a hex code or a color name given by colors

alpha, expandBB, extent, bg, add

arguments described in mf_map

leg_*

legend arguments described in mf_map. See details for arguments with two values.

Value

x is (invisibly) returned.

Details

Legend arguments that need two values are: 'leg_title', 'leg_val_rnd', and 'leg_horiz'. The first values refers to the proportional symbols legend, the second one to the choropleth legend.

See also

mf_map(), mf_map_prop, mf_map_choro, mf_distr(), mf_get_breaks(), mf_get_pal()

Examples

mtq <- mf_get_mtq()
mf_map(mtq)
mtq[6, "MED"] <- NA
mf_map(
  x = mtq, var = c("POP", "MED"), type = "prop_choro",
  inches = .2,
  val_max = 90000, symbol = "circle",
  col_na = "grey90", pal = "Cividis",
  breaks = "msd", nbreaks = 4, lwd = 1,
  leg_pos = "topright",
  leg_title = c("Population", "Median Income"),
  leg_val_rnd = c(0, 1),
  leg_horiz = c(TRUE, FALSE),
  leg_title_cex = .9,
  leg_val_dec = ",",
  leg_val_cex = .8,
  leg_size = 1,
  add = TRUE
)