mf_grad function

Plot graduated symbols

Plot graduated symbols based on quantitative data.

mf_grad(
  x,
  var,
  breaks = "quantile",
  nbreaks = 3,
  col = "tomato4",
  border = getOption("mapsf.fg"),
  pch = 21,
  cex,
  lwd,
  leg_pos = mf_get_leg_pos(x),
  leg_title = var,
  leg_title_cex = 0.8,
  leg_val_cex = 0.6,
  leg_val_rnd = 2,
  leg_frame = FALSE,
  leg_adj = c(0, 0),
  leg_size = 1,
  leg_border = border,
  leg_box_cex = c(1, 1),
  leg_fg = getOption("mapsf.fg"),
  leg_bg = getOption("mapsf.bg"),
  leg_frame_border = getOption("mapsf.fg"),
  add = TRUE
)

Arguments

• x: object of class sf
• var: name(s) of the variable(s) to plot
• breaks: either a numeric vector with the actual breaks, or a classification method name (see mf_get_breaks and Details)
• nbreaks: number of classes
• col: color
• border: border color
• pch: pch (point type) for symbols
• cex: cex (point size) for symbols
• lwd: border width
• leg_pos: position of the legend, one of 'topleft', 'top','topright', 'right', 'bottomright', 'bottom', 'bottomleft', 'left' or a vector of two coordinates in map units (c(x, y)). If leg_pos = NA then the legend is not plotted. If leg_pos = 'interactive' click onthe map to choose the legend position.
• leg_title: legend title
• leg_title_cex: size of the legend title
• leg_val_cex: size of the values in the legend
• leg_val_rnd: number of decimal places of the values in the legend
• leg_frame: whether to add a frame to the legend (TRUE) or not (FALSE)
• leg_adj: adjust the postion of the legend in x and y directions
• leg_size: size of the legend; 2 means two times bigger
• leg_border: symbol border color(s)
• leg_box_cex: width and height size expansion of boxes
• leg_fg: color of the legend foreground
• leg_bg: color of the legend backgournd
• leg_frame_border: border color of the legend frame
• add: whether to add the layer to an existing plot (TRUE) or not (FALSE)

Returns

x is (invisibly) returned.

Details

Breaks defined by a numeric vector or a classification method are left-closed: breaks defined by c(2, 5, 10, 15, 20)

will be mapped as [2 - 5[, [5 - 10[, [10 - 15[, [15 - 20]. The "jenks" method is an exception and has to be right-closed. Jenks breaks computed as c(2, 5, 10, 15, 20)

will be mapped as [2 - 5], ]5 - 10], ]10 - 15], ]15 - 20].

Examples

mtq <- mf_get_mtq()
mf_map(mtq)
mf_map(mtq, "POP", "grad", pch = 22)