Combine legend in ggplot2 - r

I have a plot of multiple geom_point and a single stat_function in ggplot2. Is there a way to show a single legend?
df <- data.frame("x"=c(1:5), "a"=c(1,2,3,3,3), "b"=c(1,1.1,1.3,1.5,1.5))
df <- melt(df, "x")
p <- ggplot(df, aes(x=x, y=value)) +
geom_point(aes(colour=variable, shape=variable)) +
stat_function(aes(colour="log2(x)"), fun=log2)
I want to have a single legend with the blue line and the two colored shapes. I tried
scale_colour_discrete(name="legend", breaks=c("a", "b", "log2(x)")) +
scale_shape_discrete(name="legend", breaks=c("a", "b"))
but this does not work. Is there a way to do this automatically or by hand?
Thanks in advance.

Probably an easier alternative is to use override.aes as follows:
ggplot(df, aes(x = x, y = value)) +
geom_point(aes(colour = variable, shape = variable), size = 3) +
stat_function(aes(colour = "log2(x)"), fun = log2, size = 1.5) +
guides(shape = FALSE,
colour = guide_legend(override.aes = list(shape = c(16, 17, NA),
linetype = c("blank", "blank", "solid"))))
which results in:

Specify a . as the shape symbol for your curve and a blank line for your points:
p <- ggplot(df, aes(x=x, y=value)) +
geom_point(aes(colour=variable, shape=variable, linetype = variable), size = 3) +
stat_function(aes(colour="log2(x)", shape = "log2(x)", linetype = "log2(x)"), fun=log2) +
scale_shape_manual(values = setNames(c(16, 17, 46), c("a", "b", "log2(x)"))) +
scale_linetype_manual(values = setNames(c(0, 0, 1), c("a", "b", "log2(x)")))
print(p)

Related

how to remove inclined lines added to legend?

How to remove inclined lines added to legend? And also the dots on the yellow and gray... Why is it happening?
library(ggplot2)
x <- seq(from = 1, to = 10, by = 1)
df = data.frame(x=x, y=x^2, v=2*x)
df2 = data.frame(x=x, y=x^2-5*x-10)
ggplot(df, aes(x, y)) +
geom_point(aes(size = v)) +
theme_classic() +
scale_size("blabla") +
geom_point(data=df2, aes(x, y, color = "blue")) +
geom_line(data=df2, aes(x, y, color = "blue")) +
geom_hline(aes(color="gray",yintercept=25)) +
geom_abline(aes(color="yellow", intercept=0, slope=1)) +
scale_color_manual(values = c("blue","gray","yellow"), labels = c("nanana","hhh","abab"), name = "other")
That's the legend for the color aesthetic and it tries to combine all the needed information for geom_point, geom_line, geom_hline, and geom_abline. To get rid of the lines, we instead need
geom_abline(aes(color = "yellow", intercept = 0, slope = 1), show.legend = FALSE)
while for the dots we have to add
guides(color = guide_legend(override.aes = list(shape = c(19, NA, NA))))
This gives

ggplot2: lines + points with white fill in plot and legend?

I want to create a plot with the ggplot2 package, which combines lines and points. The points should have colors and shapes according to a group indicator. A legend should be created, which displays colors and shapes according to the plot.
This part worked fine. However, all points should have a white fill and I cannot find the right code for that.
A google search suggests to use fill = "white", but this is not working.
Consider the following example data and plot:
library("ggplot2")
# Example data
df <- data.frame(y = 1:100,
x = 1:100,
group = as.factor(c(rep(1, 33), rep(2, 33), rep(3, 34))))
# Create plot --> fill = "white" doesnt work
ggplot(df, aes(x = x, y = y)) +
geom_line(aes(colour = factor(group, labels = c("a", "b", "c")))) +
geom_point(aes(colour = factor(group, labels = c("a", "b", "c")),
shape = factor(group, labels = c("a", "b", "c"))),
fill = "white") + ##### This line is not working #####
theme(legend.title = element_blank())
Question: How could I fill the points of this plot with white (both in the plot and the legend)?
You can use scale_shape_discrete to set solid = FALSE:
ggplot(df, aes(x = x, y = y)) +
geom_line(aes(colour = factor(group, labels = c("a", "b", "c")))) +
scale_shape_discrete(solid = F) +
geom_point(aes(colour = factor(group, labels = c("a", "b", "c")),
shape = factor(group, labels = c("a", "b", "c")))) +
theme(legend.title = element_blank())
The default shapes used by ggplot2 only have a colour: to get both a
colour and a fill, you have to use point shapes from 21 to 25. Then setting
fill = "white" will work:
library(ggplot2)
df <- data.frame(
y = 1:10, x = 1:10,
group = factor(rep(1:3, c(3, 3, 4)), labels = letters[1:3])
)
ggplot(df, aes(x = x, y = y, colour = group)) +
geom_line() +
geom_point(aes(shape = group), fill = "white", size = 3) +
theme(legend.title = element_blank()) +
scale_shape_manual(values = 20 + seq_along(unique(df$group)))
Coming up with a solution if you are not using standard shapes 21:25. The trick is to call geom_point twice, one with shape 21 to clean up the overlapping line, and another to overlay the desired shapes.
library(ggplot2)
library(RColorBrewer)
Paired = brewer.pal(n=10, name="Paired")
unicodeShapes = -10122:-10131
df = data.frame(y = 1:10, x = 1:10, labels = LETTERS[1:10])
ggplot(data=df,aes(x=x, y=y)) +
geom_line(color="gray50") +
geom_point(aes(x=x, y=y), color="white", shape=-9679, fill="white", size=5.0,show.legend=FALSE) +
geom_point(aes(color=labels, shape=labels), size=6.5) +
scale_shape_manual(name="Labels",values=unicodeShapes) +
scale_color_manual(name="Labels",values=Paired) +
theme_classic()+
theme(axis.line.x=element_line(color="gray20", size=1.0),
axis.line.y=element_line(color="gray20", size=0.5),
panel.grid.major.x=element_blank(),
panel.grid.minor=element_blank(),
panel.border=element_rect(colour="gray50",fill=NA,size=1.0),
panel.background = element_rect(colour = "gray50", size=1.0),
legend.position="bottom",
text=element_text(size=18))
Shapes on top of line

ggplot2 facet_grid create panels on the y-axis

I have similar data like the following example:
dat1 <- data.frame(group=c("a", "a","a", "a","a","a","b","b","b","b","b", "b", "b","b","b","c","c","c","c","c","c"),
subgroup=c(paste0("R", rep(1:6)),paste0("R", rep(1:9)),paste0("R", rep(1:6))),
value=c(15,16,12,12,14,5,14,27,20,23,14,10,20,22,14,15,18,14,23,30,32),
pp=c("AT","BT","CT","AA","CC","SE","DN","AS","MM","XT","QQ","HH","MK","HT","dd","US","AG","TT","ZZ","XK","RU"),
clusters=c(rep("cluster1",6),rep("cluster2",9),rep("cluster3",6)))
colors <- c(rep("#74c1e8",6),rep("#808000",9),rep("#FF69B4",6))
names(colors) <- c("cluster1","cluster2","cluster3")
my code is :
pl <- ggplot(dat1, aes(y = pp, x = subgroup))
+ geom_point(aes(size=value))
+ facet_grid(~group, scales="free_x", space = "free")
+ ylab("names")
+ xlab(" ")
+ theme(axis.text.y = element_text(color=colors))
pl
What I want is to add some space on y_axis after each cluster. For example, after cluster 3 (red ones) I want to add some space like space between panels, etc. in the following plot.
Is there a way to do that?
My solution converts the y axis to a factor and add geom_hline between each cluster
library(tidyverse)
dat1 <- data.frame(group=c("a", "a","a", "a","a","a","b","b","b","b","b", "b", "b","b","b","c","c","c","c","c","c"),
subgroup=c(paste0("R", rep(1:6)),paste0("R", rep(1:9)),paste0("R", rep(1:6))),
value=c(15,16,12,12,14,5,14,27,20,23,14,10,20,22,14,15,18,14,23,30,32),
pp=c("AT","BT","CT","AA","CC","SE","DN","AS","MM","XT","QQ","HH","MK","HT","dd","US","AG","TT","ZZ","XK","RU"),
clusters=c(rep("cluster1",6),rep("cluster2",9),rep("cluster3",6)))
colors <- c(rep("#74c1e8",6),rep("#808000",9),rep("#FF69B4",6))
names(colors) <- c("cluster1","cluster2","cluster3")
ggplot(dat1, aes(y = factor(pp), x = subgroup)) + geom_point(aes(size=value)) + facet_grid(~group, scales="free_x", space = "free")+
ylab("names") +
xlab(" ") +
theme(axis.text.y = element_text(color=colors)) +
geom_hline(yintercept = 15.5, color = "white", size = 2) +
geom_hline(yintercept = 6.5, color = "white", size = 2)

Legend for additional points in a ggplot

Steeling the example of this question (Link), I want to ask if it is possible to add the additional blue point to the legend?
dat <- data.frame(cond = rep(c("A", "B"), each=10),
xvar = 1:20 + rnorm(20,sd=3),
yvar = 1:20 + rnorm(20,sd=3))
g1 <- dat[15,]
ggplot(dat, aes(x = xvar, y = yvar, shape = cond,
colour = cond), size = 2.5) +
geom_point(alpha = 1) +
geom_point(data = g1, colour = "blue", size = 4, show_guide = FALSE)
You can put the aesthetics for the additional points layer inside aes instead of outside to get it added to the legend. You can use any string value; that string will be the name in the legend.
Then you can control the color and shape of that point via scale_*_manual layers.
I additionally changed the size of that point in the legend using override.aes, which is optional.
ggplot(dat, aes(x = xvar, y = yvar, shape = cond,
colour = cond), size = 2.5) +
geom_point(alpha = 1) +
geom_point(data = g1, aes(colour = "Point 15", shape = "Point 15"), size = 4) +
scale_shape_manual(values = c(16, 17, 17) ) +
scale_color_manual(values = c("pink", "turquoise", "blue") ) +
guides(color = guide_legend( override.aes = list(size = c(1.5, 1.5, 4) ) ) )
You probably have to change the condition of that point in the data as in your example or add it to the date, if it is not already part of it.
dat <- data.frame(cond = rep(c("A", "B"), each=10),
xvar = 1:20 + rnorm(20,sd=3),
yvar = 1:20 + rnorm(20,sd=3))
dat$size = 2.5
dat[15,]$cond = "C"
dat$cond = as.character(dat$cond)
dat[15,]$size = 4
ggplot(dat, aes(x = xvar, y = yvar, shape = cond,
colour = cond, size=size)) +
geom_point(alpha = 1) +
scale_colour_manual(values=c("red", "turquoise", "blue")) +
scale_size_continuous(guide = FALSE)

Combine redundant legend items in ggplot2

Here's my data:
# Data:
mydf <- data.frame(
Species = rep(c("Ungulate","Ungulate","Elk","Elk","Rodent","Rodent","Deer","Deer"),
times = 3),
Space = rep(c("W", "C", "E"), each = 8),
Age = rep(c("Adult", "Juvenile"), times = 12),
value = c(0.03,0.17,0.02,0.23,0.33,0.00,0.05,0.12,0.04,0.28,0.09,0.23,0.17,0.00,0.13,
0.17,0.02,0.14,0.01,0.23,0.29,0.00,0.06,0.13))
mydf$spaceage <- as.factor(paste(mydf$Space, mydf$Age))
mydf
myPalette <- c("#f4a582", "#b2182b", "#92c5de", "#2166ac", "#a6dba0", "#1b7837")
For my plot:
example <- ggplot(mydf,
aes(x = factor(Space, levels = c("W", "C", "E")),
y = value,
fill = factor(spaceage))) +
geom_bar(stat = 'identity', position = 'stack') +
facet_grid(~ Species) +
scale_fill_manual(values = myPalette, name = "Age") + #legend
labs(x="") +
theme_bw()
example
Returns:
Is it possible to combine redundant legend items, so dark and light shades are combined, to produce something like this? (couldn't get very even sizes using paint):
I'm open to other ideas for making this legend more concise. Thanks for any advice!
You can assign "" as legend label to some legend entries in order to achieve the effect.
However, I would first of all caution to be very careful with the manual fill scale first, as you want to make sure each colour corresponds to the correct spaceage value before obscuring its label.
Here's an implementation:
# ensure correct mapping between colour & label
names(myPalette) <- levels(mydf$spaceage)
ggplot(mydf,
aes(x = factor(Space, levels = c("W", "C", "E")),
y = value,
fill = factor(spaceage))) +
# minor point, but geom_col() is equivalent to geom_bar(position = "identity"),
# and position = "stack" is default in both cases.
geom_col() +
facet_grid(~ Species) +
scale_fill_manual(values = myPalette, name = "Age",
# ensures colour order follows x-axis order
breaks = c("W Adult", "W Juvenile", "C Adult", "C Juvenile",
"E Adult", "E Juvenile"),
# comment out this line to verify that right colour
# is mapped to the right label
labels = c("", "", "", "", "Adult", "Juvenile"),
# specify 2 rows for legends
guide = guide_legend(nrow = 2, byrow = FALSE)) +
labs(x = "") +
theme_bw()
Create the legend, which is actually a ggplot2.
library(ggplot2)
ds_palette <- tibble::tibble(
fill = c("#a6dba0", "#1b7837", "#f4a582", "#b2182b", "#92c5de", "#2166ac"),
x = c(2, 1, 2, 1, 2, 1),
y = c(3, 3, 2, 2, 1, 1),
text = c("W", "W", "C", "C", "E", "E"),
text_color = c("black", "white", "black", "white", "black", "white")
)
legend_inset <- ggplot(ds_palette, aes(x=x, y=y, fill=fill)) +
geom_tile() +
geom_text(aes(label=text, color=text_color)) +
annotate("text", x=1, y=3.6, label="Juvenile", vjust=0) +
annotate("text", x=2, y=3.6, label="Adult", vjust=0) +
scale_color_identity() +
scale_fill_identity() +
coord_cartesian(ylim=c(0.5, 4), expand = F) +
theme_void() +
labs(x="")
Then put it all together. The objects in vpList define the proportions of the partitioned areas.
grid.newpage()
plot_width <- .8
tree <- vpTree(
viewport(w=1, h=1, name="A"),
vpList(
viewport(x=0, y=0 , w= plot_width, h=1 , just=c("left", "bottom"), name="bar_graph"),
viewport(x=1, y=.5, w=1-plot_width, h=0.3, just=c("right", "top") , name="legend")
)
)
pushViewport(tree)
print(example , vp = "bar_graph")
print(legend_inset, vp = "legend")
I rotated your 2x3 legend so the words would be more space-efficient.
You can add labels and change the position of your legend as the code below.
example<-ggplot(mydf, aes(x = factor(Space, levels=c("W", "C", "E")), y = value, fill = factor(spaceage))) +
geom_bar(stat = 'identity', position = 'stack') + facet_grid(~ Species) +
scale_fill_manual(values = myPalette,name = "Age",labels=c("Adult","Juvenile","Adult","Juvenile","Adult","Juvenile")) + #legend
labs(x="") +
theme(legend.position = "top")
example
The result looks like below.

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