R: Plot a single map legend

leg {maplegend}

R Documentation

Plot a single map legend

Description

Plot different types of legend. The "type" argument defines the legend type. Please note that some arguments are available for all types of legend and some others are only relevant for specific legend types (see Details).

Usage

leg(
  type,
  val,
  pos = "left",
  pal = "Inferno",
  col = "tomato4",
  inches = 0.3,
  symbol = "circle",
  self_adjust = FALSE,
  lwd = 0.7,
  border = "#333333",
  pch = seq_along(val),
  cex = rep(1, length(val)),
  title = "Legend Title",
  title_cex = 0.8 * size,
  val_cex = 0.6 * size,
  val_rnd = 0,
  col_na = "white",
  cex_na = 1,
  pch_na = 4,
  no_data = FALSE,
  no_data_txt = "No Data",
  box_border = "#333333",
  box_cex = c(1, 1),
  horiz = FALSE,
  frame_border = fg,
  frame = FALSE,
  bg = "#f7f7f7",
  fg = "#333333",
  size = 1,
  return_bbox = FALSE,
  mar = par("mar"),
  adj = c(0, 0)
)

Arguments

`type`	type of legend: prop for proportional symbols, choro for choropleth maps, cont for continuous maps (e.g. raster), typo for typology maps, symb for symbols maps, prop_line for proportional lines maps, grad_line for graduated lines maps.
`val`	vector of value(s) (for "prop" and "prop_line", at least c(min, max) for "cont"), vector of categories (for "symb" and "typo"), break labels (for "choro" and "grad_line").
`pos`	position of the legend. It can be one of 'topleft', 'top', 'topright', 'right', 'bottomright', 'bottom','bottomleft', 'left', 'interactive' or a vector of two coordinates in map units (c(x, y)).
`pal`	a color palette name or a vector of colors
`col`	color of the symbols (for "prop") or color of the lines (for "prop_line" and "grad_line")
`inches`	size of the largest symbol (radius for circles, half width for squares) in inches
`symbol`	type of symbols, 'circle' or 'square'
`self_adjust`	if TRUE values are self-adjusted to keep min, max and intermediate rounded values
`lwd`	width(s) of the symbols borders (for "prop" and "symb"), width of the largest line (for "prop_line"), vector of line width (for "grad_line")
`border`	symbol border color(s)
`pch`	type(s) of the symbols (0:25)
`cex`	size(s) of the symbols
`title`	title of the legend
`title_cex`	size of the legend title
`val_cex`	size of the values in the legend
`val_rnd`	number of decimal places of the values in the legend
`col_na`	color for missing values
`cex_na`	size of the symbols for missing values
`pch_na`	type of the symbols for missing values
`no_data`	if TRUE a "missing value" box is plotted
`no_data_txt`	label for missing values
`box_border`	border color of legend boxes
`box_cex`	width and height size expansion of boxes, (or offset between circles for "prop" legends with horiz = TRUE)
`horiz`	if TRUE plot an horizontal legend
`frame_border`	border color of the frame
`frame`	if TRUE the legend is plotted within a frame
`bg`	background color of the legend
`fg`	foreground color of the legend
`size`	size of the legend; 2 means two times bigger
`return_bbox`	return only bounding box of the legend. No legend is plotted.
`mar`	plot margins
`adj`	adjust the postion of the legend in x and y directions.

Details

Some arguments are available for all types of legend: val, pos, title, title_cex, val_cex, frame, bg, fg, size, adj, return_bbox and mar).

Relevant arguments for each specific legend types:

leg(type = "prop", val, inches, symbol, col, lwd, border, val_rnd, self_adjust, horiz)
leg(type = "choro", val, pal, val_rnd, col_na, no_data, no_data_txt, box_border, horiz)
leg(type = "cont", val, pal, val_rnd, col_na, no_data, no_data_txt, box_border, horiz)
leg(type = "typo", val, pal, col_na, no_data, no_data_txt, box_border)
leg(type = "symb", val, pal, pch, cex, lwd, pch_na, cex_na, col_na, no_data, no_data_txt)
leg(type = "prop_line", val, col, lwd, val_rnd)
leg(type = "grad_line", val, col, lwd, val_rnd)

Value

No value is returned, a legend is displayed.

Examples

# minimal example
plot.new()
plot.window(xlim = c(0, 1), ylim = c(0, 1), asp = 1)
box()
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)
)

plot.new()
plot.window(xlim = c(0, 1), ylim = c(0, 1), 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 = "topright",
  horiz = FALSE
)
box()

# full example
plot.new()
plot.window(xlim = c(0, 1), ylim = c(0, 1), asp = 1)
leg(
  type = "prop",
  val = c(5, 100),
  pos = "top",
  inches = .4,
  symbol = "circle",
  col = "#940000",
  lwd = 1,
  border = "#9494ff",
  val_rnd = 1,
  self_adjust = TRUE,
  title = "Proportional Symbols",
  title_cex = 1,
  val_cex = .8,
  bg = "grey10",
  fg = "yellow",
  frame = TRUE
)

plot.new()
plot.window(xlim = c(0, 1), ylim = c(0, 1), asp = 1)
leg(
  type = "choro",
  val = c(10, 20, 30, 40, 50),
  pos = "top",
  pal = c("#7F000D", "#B56C6F", "#DBBABB", "#F1F1F1"),
  val_rnd = 2,
  col_na = "grey",
  no_data = TRUE,
  no_data_txt = "No data",
  box_border = "cornsilk",
  box_cex = c(2, 1),
  title = "Choropleth (sequential)"
)

plot.new()
plot.window(xlim = c(0, 1), ylim = c(0, 1), asp = 1)
leg(
  type = "typo",
  val = c("A", "B", "C"),
  pos = "top",
  pal = "Dynamic",
  col_na = "grey",
  no_data = TRUE,
  no_data_txt = "No data",
  box_cex = c(1.2, 1),
  title = "Typology (categories)"
)

plot.new()
plot.window(xlim = c(0, 1), ylim = c(0, 1), asp = 1)
leg(
  type = "symb",
  val = c("A", "B", "C"),
  pos = "top",
  pch = 21:23,
  cex = c(4, 4, 2),
  pal = "Inferno",
  lwd = 2,
  border = "red",
  col_na = "grey",
  pch_na = 3,
  cex_na = 1,
  no_data = TRUE,
  no_data_txt = "No data",
  title = "Symbols"
)

plot.new()
plot.window(xlim = c(0, 1), ylim = c(0, 1), asp = 1)
leg(
  type = "cont",
  val = c(1, 2, 3, 4, 5),
  pos = "top",
  pal = "Inferno",
  val_rnd = 2,
  horiz = TRUE,
  box_cex = c(2, 1),
  title = "Continuous"
)

plot.new()
plot.window(xlim = c(0, 1), ylim = c(0, 1), asp = 1)
leg(
  type = "prop_line",
  val = c(54, 505, 1025),
  pos = "top",
  lwd = 15,
  col = "green",
  val_rnd = -1,
  box_cex = c(2, .5),
  title = "Proportional Lines",
  bg = "black",
  fg = "white",
  frame = TRUE
)

plot.new()
plot.window(xlim = c(0, 1), ylim = c(0, 1), asp = 1)
leg(
  type = "grad_line",
  val = c(1.25, 4.07, 10.001, 15.071),
  pos = "top",
  lwd = c(1, 7, 15),
  col = "#C130ff",
  val_rnd = 3,
  box_cex = c(2, 1),
  title = "Graduated Lines"
)

# Positions
plot.new()
plot.window(xlim = c(0, 1), ylim = c(0, 1), asp = 1)
leg(
  type = "prop", val = c(10, 50, 100), pos = "bottomleft", adj = c(0, 1),
  title = "bottomleft1"
)
leg(
  type = "choro", val = c(10, 50, 100), pos = "bottomright",
  adj = c(0, 2), title = "bottomright2", frame = TRUE
)
leg(
  type = "prop", val = c(10, 50, 100), pos = "topleft",
  adj = c(0, -2), title = "topleft2"
)
box()
mtext(
  text = "A small text on 1 line", side = 1, adj = .01,
  line = -1, cex = .8
)
mtext(
  text = "A small text\non 2 lines", side = 1, adj = .99,
  line = -1, cex = .8
)
mtext(
  text = "A large text on 1 line", side = 3, adj = .01,
  line = -1.5, cex = 1.2
)

[Package maplegend version 0.1.0 Index]