/
guide_legend.Rd
170 lines (135 loc) · 5.39 KB
/
guide_legend.Rd
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
\name{guide_legend}
\alias{guide_legend}
\title{Legend guide.}
\usage{
guide_legend(title = waiver(), title.position = NULL,
title.theme = NULL, title.hjust = NULL,
title.vjust = NULL, label = TRUE,
label.position = NULL, label.theme = NULL,
label.hjust = NULL, label.vjust = NULL,
keywidth = NULL, keyheight = NULL, direction = NULL,
default.unit = "line", override.aes = list(),
nrow = NULL, ncol = NULL, byrow = FALSE,
reverse = FALSE, ...)
}
\arguments{
\item{title}{A character string or expression indicating
a title of guide. If \code{NULL}, the title is not
shown. By default (\code{\link{waiver}}), the name of the
scale object or tha name specified in \code{\link{labs}}
is used for the title.}
\item{title.position}{A character string indicating the
position of a title. One of "top" (default for a vertical
guide), "bottom", "left" (default for a horizontal
guide), or "right."}
\item{title.theme}{A theme object for rendering the title
text. Usually the object of \code{\link{theme_text}} is
expected. By default, the theme is specified by
\code{legend.title} in \code{\link{opts}} or theme.}
\item{title.hjust}{A number specifying horizontal
justification of the title text.}
\item{title.vjust}{A number specifying vertical
justification of the title text.}
\item{label}{logical. If \code{TRUE} then the labels are
drawn. If \code{FALSE} then the labels are invisible.}
\item{label.position}{A character string indicating the
position of a label. One of "top", "bottom" (default for
horizontal guide), "left", or "right" (default for
vertical gudie).}
\item{label.theme}{A theme object for rendering the label
text. Usually the object of \code{\link{theme_text}} is
expected. By default, the theme is specified by
\code{legend.text} in \code{\link{opts}} or theme.}
\item{label.hjust}{A numeric specifying horizontal
justification of the label text.}
\item{label.vjust}{A numeric specifying vertical
justification of the label text.}
\item{keywidth}{A numeric or a unit object specifying the
width of the legend key. Default value is
\code{legend.key.width} or \code{legend.key.size} in
\code{\link{opts}} or theme.}
\item{keyheight}{A numeric or a unit object specifying
the height of the legend key. Default value is
\code{legend.key.height} or \code{legend.key.size} in
\code{\link{opts}} or theme.}
\item{direction}{A character string indicating the
direction of the guide. One of "horizontal" or
"vertical."}
\item{default.unit}{A character string indicating unit
for \code{keywidth} and \code{keyheight}.}
\item{override.aes}{A list specifying aesthetic
parameters of legend key. See details and examples.}
\item{nrow}{The desired number of rows of legends.}
\item{ncol}{The desired number of column of legends.}
\item{byrow}{logical. If \code{FALSE} (the default) the
legend-matrix is filled by columns, otherwise the
legend-matrix is filled by rows.}
\item{reverse}{logical. If \code{TRUE} the order of
legends is reversed.}
\item{...}{ignored.}
}
\value{
A guide object
}
\description{
Legend type guide shows key (i.e., geoms) mapped onto
values. Legend guides for various scales are integrated
if possible.
}
\details{
Guides can be specified in each scale or in
\code{\link{guides}}. \code{guide="legend"} in scale is
syntactic sugar for \code{guide=guide_legend()}. As for
how to specify the guide for each scales in more detail,
see \code{\link{guides}}.
}
\examples{
\donttest{
library(reshape2) # for melt
df <- melt(outer(1:4, 1:4), varnames = c("X1", "X2"))
p1 <- ggplot(df, aes(X1, X2)) + geom_tile(aes(fill = value))
p2 <- p1 + geom_point(aes(size = value))
# Basic form
p1 + scale_fill_continuous(guide = "legend")
p1 + scale_fill_continuous(guide = guide_legend())
# Guide title
p1 + scale_fill_continuous(guide = guide_legend(title = "V")) # title text
p1 + scale_fill_continuous(name = "V") # same
p1 + scale_fill_continuous(guide = guide_legend(title = NULL)) # no title
# Control styles
# key size
p1 + guides(fill = guide_legend(keywidth = 3, keyheight = 1))
# title position
p1 + guides(fill = guide_legend(title = "LEFT", title.position = "left"))
# title text styles via theme_text
p1 + guides(fill = guide_legend(
title.theme = theme_text(size=15, face="italic", col="red", angle=45)))
# label position
p1 + guides(fill = guide_legend(label.position = "bottom"))
# label styles
p1 + scale_fill_continuous(breaks = c(5, 10, 15),
labels = paste("long", c(5, 10, 15)),
guide = guide_legend(direction = "horizontal", title.position = "top",
label.position="bottom", label.hjust = 0.5, label.vjust = 0.5,
label.theme = theme_text(angle = 90)))
# Set aesthetic of legend key
# very low alpha value make it difficult to see legend key
p3 <- qplot(carat, price, data = diamonds, colour = color,
alpha = I(1/100))
p3
# override.aes overwrites the alpha
p3 + guides(colour = guide_legend(override.aes = list(alpha = 1)))
# multiple row/col legends
p <- qplot(1:20, 1:20, colour = letters[1:20])
p + guides(col = guide_legend(nrow = 8))
p + guides(col = guide_legend(ncol = 8))
p + guides(col = guide_legend(nrow = 8, byrow = TRUE))
p + guides(col = guide_legend(ncol = 8, byrow = TRUE))
# reversed order legend
p + guides(col = guide_legend(reverse = TRUE))
}
}
\seealso{
Other guides: \code{\link{guide_colorbar}},
\code{\link{guide_colourbar}}, \code{\link{guides}}
}