grid_legend: Legend Function for grid Graphics

In vcd: Visualizing Categorical Data

Legend Function for grid Graphics

Description

This function can be used to add legends to grid-based plots.

Usage

grid_legend(x, y, pch = NA, col = par('col'), labels, frame = TRUE,
            hgap = unit(0.8, "lines"), vgap = unit(0.8, "lines"),
            default_units = "lines", gp = gpar(), draw = TRUE,
            title = NULL, just = 'center', lwd = NA, lty = NA,
            size = 1,
            gp_title = NULL, gp_labels = NULL,
            gp_frame = gpar(fill = "transparent"),
            inset = c(0, 0))

Arguments

x	character string "topright", "topleft", "bottomright", "bottomleft", "top", "bottom", "left", "right", "center" or x coordinate of the legend.
y	y coordinates of the legend.
pch	integer vector of plotting symbols, if any.
col	character vector of colors for the symbols.
labels	character vector of labels corresponding to the symbols.
frame	logical indicating whether the legend should have a border or not.
hgap	object of class "unit" specifying the space between symbols and labels.
vgap	object of class "unit" specifying the space between the lines.
default_units	character string indicating the default unit.
gp	object of class "gpar" used for the legend.
draw	logical indicating whether the legend be drawn or not.
title	character string indicating the plot's title.
just	justification of the legend relative to its (x, y) location. see ?viewport for more details.
lwd	positive number to set the line width. if specified lines are drawn.
lty	line type. if specified lines are drawn.
size	size of the group symbols (in char units).
gp_title	object of class "gpar" used for the title.
gp_labels	object of class "gpar" used for the labels.
gp_frame	object of class "gpar" used for the frame.
inset	numeric vector of length 2 specifying the inset of the legend in npc units, relative to the specified x and y coordinates.

Value

Invisibly, the legend as a "grob" object.

Author(s)

David Meyer [e-mail] Florian Gerber [e-mail]

See Also

legend

Examples

data("Lifeboats")
attach(Lifeboats)
ternaryplot(Lifeboats[,4:6],
  pch = ifelse(side == "Port", 1, 19),
  col = ifelse(side == "Port", "red", "blue"),
  id  = ifelse(men / total > 0.1, as.character(boat), NA),
  prop_size = 2,
  dimnames_position = "edge",
  main = "Lifeboats on Titanic")
grid_legend(0.8, 0.9, c(1, 19), c("red", "blue"),
  c("Port", "Starboard"), title = "SIDE")


grid.newpage()
pushViewport(viewport(height = .9, width = .9 ))
grid.rect(gp = gpar(lwd = 2, lty = 2))

grid_legend(x = unit(.05,'npc'),
            y = unit(.05,'npc'),
            just = c(0,0),
            pch = c(1,2,3),
            col = c(1,2,3),
            lwd=NA, 
            lty=NA,
            labels = c("b",'r','g'),
            title = NULL,
            gp=gpar(lwd=2, cex=1),
            hgap = unit(.8, "lines"),
            vgap = unit(.9, "lines"))

grid_legend(x = unit(1,'npc'),
            y = unit(1,'npc'),
            just = c(1,1),
            pch = NA,
            col = c(1,2,3,4),
            lwd=c(1,1,1,3), 
            lty=c(1,2,1,3),
            labels = c("black",'red','green','blue'),
            gp_labels = list(gpar(col = 1), gpar(col = 2), gpar(col = 3), gpar(col = 4)),
            title = NULL,
            gp=gpar(lwd=2, cex=1),
            hgap = unit(.8, "lines"),
            vgap = unit(.9, "lines"))

grid_legend(x = 'topleft',
            pch = c(1,NA,2,NA),
            col = c(1,2,3,4),
            lwd=NA, 
            lty=c(NA,2,NA,3),
            labels = c("black",'red','green','blue'),
            title = 'Some LONG Title',
            gp_title = gpar(col = 3),
            gp_frame = gpar(col = 4, lty = 2, fill = "transparent"),
            gp_labels = gpar(col = 6),
            gp=gpar(lwd=2, cex=2, col = 1),
            hgap = unit(.8, "lines"),
            vgap = unit(.9, "lines"))

grid_legend(x = .7,
            y = .7,
            pch = c(1,NA,2,NA),
            col = c(1,2,3,4),
            lwd=1, 
            lty=c(NA,2,NA,3),
            labels = c("black",'red','green','blue'),
            title = 'short T',
            gp=gpar(lwd=1, cex=.7,col = 1),
            hgap = unit(.8, "lines"),
            vgap = unit(.9, "lines"))

grid_legend(x = 'bottomright',
            pch = c(1,NA,2,NA),
            col = c(2),
            lwd=NA, 
            lty=c(NA,2,NA,3),
            labels = c("black",'red','green','blue'),
            title = NULL,
            gp=gpar(lwd=2, cex=1,col = 1),
            hgap = unit(.8, "lines"),
            vgap = unit(.9, "lines"))

vcd documentation built on Sept. 17, 2024, 1:08 a.m.