I have the following code:
library(ggplot2)
df <- data.frame(iris) # iris dataset
pca <- prcomp(df[,1:4], retx=T, scale.=T) # scaled pca [exclude species col]
scores <- pca$x[,1:3] # scores for first three PC's
# k-means clustering [assume 3 clusters]
km <- kmeans(scores, centers=3, nstart=5)
ggdata <- data.frame(scores, Cluster=km$cluster, Species=df$Species)
# stat_ellipse is not part of the base ggplot package
source("https://raw.githubusercontent.com/tidyverse/ggplot2/master/R/stat-ellipse.R")
ggplot(ggdata) +
geom_point(aes(x=PC1, y=PC2, color=factor(Species)), size=5, shape=20) +
stat_ellipse(aes(x=PC1,y=PC2,fill=factor(Species)),
geom="polygon", level=0.95, alpha=0.2) +
guides(color=guide_legend("Species"),fill=guide_legend("Cluster"))
Which produces this:
As stated in that picture how do I just remove 'Cluster' legend?
Set your fill guide to "none"
ggplot(ggdata) +
geom_point(aes(x=PC1, y=PC2, color=factor(Species)), size=5, shape=20) +
stat_ellipse(aes(x=PC1,y=PC2, fill=factor(Species)),
geom="polygon", level=0.95, alpha=0.2)+
guides(color=guide_legend("Species"), fill = "none")
Edit: 20221129 - changed scale = FALSE to scale = "none", as per:
The <scale> argument of guides() cannot be FALSE. Use "none" instead as of ggplot2
3.3.4.
Related
I am creating dendrograms using ggdendro and coloring them according to cutpoints in the branches. I'm using the approach provided by #jlhoward in this question (Colorize Clusters in Dendogram with ggplot2) but I run into problems when my leaf labels are very long.
Here is some example code:
df <- USArrests
labs <- paste("veryverylongtitlename",1:50,sep="")
rownames(df) <- labs
library(ggplot2)
library(ggdendro)
hc <- hclust(dist(df), "ave") # heirarchal clustering
dendr <- dendro_data(hc, type="rectangle") # convert for ggplot
clust <- cutree(hc,k=2) # find 2 clusters
clust.df <- data.frame(label=names(clust), cluster=factor(clust))
# dendr[["labels"]] has the labels, merge with clust.df based on
label column
dendr[["labels"]] <- merge(dendr[["labels"]],clust.df, by="label")
# plot the dendrogram; note use of color=cluster in geom_text(...)
ggplot() +
geom_segment(data=segment(dendr), aes(x=x, y=y, xend=xend,
yend=yend)) +
geom_text(data=label(dendr), aes(x, y, label=label, hjust=0, color=cluster),
size=3) +
coord_flip() + scale_y_reverse(expand=c(0.2, 0)) +
theme(axis.line.y=element_blank(),
axis.ticks.y=element_blank(),
axis.text.y=element_blank(),
axis.title.y=element_blank(),
panel.background=element_rect(fill="white"),
panel.grid=element_blank())
As you can see, the labels here get cut off. I found this answer (decrease size of dendogram (or y-axis) ggplot), but I don't want to use it because I very much like the ability to use cutree to define my clusters. How can I manipulate the above code to fit the long labels? Many thanks!
I have scatterplots of 2D data from two categories. I want to add density lines for each dimension -- not outside the plot (cf. Scatterplot with marginal histograms in ggplot2) but right on the plotting surface. I can get this for the x-axis dimension, like this:
set.seed(123)
dim1 <- c(rnorm(100, mean=1), rnorm(100, mean=4))
dim2 <- rnorm(200, mean=1)
cat <- factor(c(rep("a", 100), rep("b", 100)))
mydf <- data.frame(cbind(dim2, dim1, cat))
ggplot(data=mydf, aes(x=dim1, y=dim2, colour=as.factor(cat))) +
geom_point() +
stat_density(aes(x=dim1, y=(-2+(..scaled..))),
position="identity", geom="line")
It looks like this:
But I want an analogous pair of density curves running vertically, showing the distribution of points in the y-dimension. I tried
stat_density(aes(y=dim2, x=0+(..scaled..))), position="identity", geom="line)
but receive the error "stat_density requires the following missing aesthetics: x".
Any ideas? thanks
You can get the densities of the dim2 variables. Then, flip the axes and store them in a new data.frame. After that it is simply plotting them on top of the other graph.
p <- ggplot(data=mydf, aes(x=dim1, y=dim2, colour=as.factor(cat))) +
geom_point() +
stat_density(aes(x=dim1, y=(-2+(..scaled..))),
position="identity", geom="line")
stuff <- ggplot_build(p)
xrange <- stuff[[2]]$ranges[[1]]$x.range # extract the x range, to make the new densities align with y-axis
## Get densities of dim2
ds <- do.call(rbind, lapply(unique(mydf$cat), function(lev) {
dens <- with(mydf, density(dim2[cat==lev]))
data.frame(x=dens$y+xrange[1], y=dens$x, cat=lev)
}))
p + geom_path(data=ds, aes(x=x, y=y, color=factor(cat)))
So far I can produce:
distrib_horiz <- stat_density(aes(x=dim1, y=(-2+(..scaled..))),
position="identity", geom="line")
ggplot(data=mydf, aes(x=dim1, y=dim2, colour=as.factor(cat))) +
geom_point() + distrib_horiz
And:
distrib_vert <- stat_density(data=mydf, aes(x=dim2, y=(-2+(..scaled..))),
position="identity", geom="line")
ggplot(data=mydf, aes(x=dim2, y=dim1, colour=as.factor(cat))) +
geom_point() + distrib_vert + coord_flip()
But combining them is proving tricky.
So far I have only a partial solution since I didn't manage to obtain a vertical stat_density line for each individual category, only for the total set. Maybe this can nevertheless help as a starting point for finding a better solution. My suggestion is to try with the ggMarginal() function from the ggExtra package.
p <- ggplot(data=mydf, aes(x=dim1, y=dim2, colour=as.factor(cat))) +
geom_point() + stat_density(aes(x=dim1, y=(-2+(..scaled..))),
position="identity", geom="line")
library(ggExtra)
ggMarginal(p,type = "density", margins = "y", size = 4)
This is what I obtain:
I know it's not perfect, but maybe it's a step in a helpful direction. At least I hope so. Looking forward to seeing other answers.
I am using ggplot2 to produce a plot that has 3 facets. Because I am comparing two different data sets, I would like to then be able to plot a second data set using the same y scale for the facets as in the first plot. However, I cannot find a simple way to save the settings of the first plot to then re-use them with the second plot. Since each facet has its own y scale, it will be a pain to specify them by hand for the second plot. Does anyone know of a quick way of re-using scales? To make this concrete, here is how I am generating first my plot:
p <- ggplot(mtcars, aes(mpg, wt)) + geom_point()
p + facet_wrap(~ cyl, scales = "free_y")
EDIT
When applying one of the suggestions below, I found out that my problem was more specific than described in the original post, and it had to do specifically with scaling of the error bars. Concretely, the error bars look weird when I rescale the second plot as suggested. Does anyone have any suggestions on how to keep the same scale for both plots and dtill display the error bars correctly? I am attaching example below for concreteness:
#Create sample data
d1 <- data.frame(fixtype=c('ff','ff','fp','fp'), detype=c('det','pro','det','pro'),
diffscore=c(-1,-15,3,-17),se=c(2,3,1,2))
d2 <- data.frame(fixtype=c('ff','ff','fp','fp'), detype=c('det','pro','det','pro'),
diffscore=c(-1,-3,-2,-1),se=c(4,3,5,3))
#Plot for data frame 1, this is the scale I want to keep
lim_d1 <- aes(ymax = diffscore + se, ymin=diffscore - se)
ggplot(d1, aes(colour=detype, y=diffscore, x=detype)) +
geom_point(aes(size=1), shape=15) +
geom_errorbar(lim_d1, width=0.2,size=1) +
facet_wrap(~fixtype, nrow=2, ncol=2, scales = "free_y")
#Plot for data frame 2 original scale
lim_d2 <- aes(ymax = diffscore + se, ymin=diffscore - se)
ggplot(d2, aes(colour=detype, y=diffscore, x=detype)) +
geom_point(aes(size=1), shape=15) +
geom_errorbar(lim_d2, width=0.2,size=1) +
facet_wrap(~fixtype, nrow=2, ncol=2, scales = "free_y")
#Plot for data frame 2 adjusted scale. This is where things go wrong!
#As suggested below, first I plot the first plot, then I draw a blank screen and try
#to plot the second data frame on top.
lim_d2 <- aes(ymax = diffscore + se, ymin=diffscore - se)
ggplot(d1, aes(colour=detype, y=diffscore, x=detype)) +
geom_blank() +
geom_point(data=d2, aes(size=1), shape=15) +
geom_errorbar(lim_d2, width=0.2,size=1) +
facet_wrap(~fixtype, nrow=2, ncol=2, scales = "free_y")
#If the error bars are fixed, by adding data=d2 to geom_errorbar(), then
#the error bars are displayed correctly but the scale gets distorted again
lim_d2 <- aes(ymax = diffscore + se, ymin=diffscore - se)
ggplot(d1, aes(colour=detype, y=diffscore, x=detype)) +
geom_blank() +
geom_point(data=d2, aes(size=1), shape=15) +
geom_errorbar(data=d2,lim_d2, width=0.2,size=1) +
facet_wrap(~fixtype, nrow=2, ncol=2, scales = "free_y")
You may first call ggplot on your original data where you add a geom_blank as a first layer. This sets up a plot area, with axes and legends based on the data provided in ggplot.
Then add geoms which use data other than the original data. In the example, I use a simple subset of the original data.
From ?geom_blank: "The blank geom draws nothing, but can be a useful way of ensuring common scales between different plots.".
ggplot(data = mtcars, aes(mpg, wt)) +
geom_blank() +
geom_point(data = subset(mtcars, wt < 3)) +
facet_wrap(~ cyl, scales = "free_y")
Here is an ugly hack that assumes you have an identical facetting layout in both plots.
It replaces the panel element of the ggplot build.
p <- ggplot(mtcars, aes(mpg, wt)) + geom_point()
p1 <- p + facet_wrap(~ cyl, scales = "free_y") + labs(title = 'original')
# create "other" data.frame
n <- nrow(mtcars)
set.seed(201405)
mtcars2 <- mtcars[sample(seq_len(n ),n-15),]
# create this second plot
p2 <- p1 %+% mtcars2 + labs(title = 'new data')
# and a copy so we can attempt to fix
p3 <- p2 + labs(title = 'new data original scale')
# use ggplot_build to construct the plots for rendering
p1b <- ggplot_build(p1)
p3b <- ggplot_build(p3)
# replace the 'panel' information in plot 2 with that
# from plot 1
p3b[['panel']] <- p1b[['panel']]
# render the revised plot
# for comparison
library(gridExtra)
grid.arrange(p1 , p2, ggplot_gtable(p3b))
How to overlay one plot on top of the other in ggplot2 as explained in the following sentences? I want to draw the grey time series on top of the red one using ggplot2 in R (now the red one is above the grey one and I want my graph to be the other way around). Here is my code (I generate some data in order to show you my problem, the real dataset is much more complex):
install.packages("ggplot2")
library(ggplot2)
time <- rep(1:100,2)
timeseries <- c(rep(0.5,100),rep(c(0,1),50))
upper <- c(rep(0.7,100),rep(0,100))
lower <- c(rep(0.3,100),rep(0,100))
legend <- c(rep("red should be under",100),rep("grey should be above",100))
dataset <- data.frame(timeseries,upper,lower,time,legend)
ggplot(dataset, aes(x=time, y=timeseries)) +
geom_line(aes(colour=legend, size=legend)) +
geom_ribbon(aes(ymax=upper, ymin=lower, fill=legend), alpha = 0.2) +
scale_colour_manual(limits=c("grey should be above","red should be under"),values = c("grey50","red")) +
scale_fill_manual(values = c(NA, "red")) +
scale_size_manual(values=c(0.5, 1.5)) +
theme(legend.position="top", legend.direction="horizontal",legend.title = element_blank())
Convert the data you are grouping on into a factor and explicitly set the order of the levels. ggplot draws the layers according to this order. Also, it is a good idea to group the scale_manual codes to the geom it is being applied to for readability.
legend <- factor(legend, levels = c("red should be under","grey should be above"))
c <- data.frame(timeseries,upper,lower,time,legend)
ggplot(c, aes(x=time, y=timeseries)) +
geom_ribbon(aes(ymax=upper, ymin=lower, fill=legend), alpha = 0.2) +
scale_fill_manual(values = c("red", NA)) +
geom_line(aes(colour=legend, size=legend)) +
scale_colour_manual(values = c("red","grey50")) +
scale_size_manual(values=c(1.5,0.5)) +
theme(legend.position="top", legend.direction="horizontal",legend.title = element_blank())
Note that the ordering of the values in the scale_manual now maps to "grey" and "red"
Is it possible to vary a plot's color gradient by aesthetic? I'm generating a plot using code similar the lines presented below and finding in some cases that it is not always easy to distinguish between the various groups. For example, on the chart below it would be easier to distinguish the results if I could have the group A points use a white-blue gradient and the group B points use a white-red gradient.
data <- data.frame(x=c(1,2,3,4,5,6,1,2,3,4,5,6),
y=c(1,2,3,4,5,6,1,2,3,4,5,6), grp=c(rep("A",6),rep("B",6)),
dt=c("2010-06-30","2010-05-31","2010-04-30",
"2010-03-31","2010-02-26","2010-01-29","2010-06-30",
"2010-05-31","2010-04-30",
"2010-03-31","2010-02-26","2010-01-29"))
p <- ggplot(data, aes(x,y,color=as.integer(as.Date(data$dt)))) +
geom_jitter(size=4, alpha=0.75, aes(shape=grp)) +
scale_colour_gradient(limits=as.integer(as.Date(c("2010-01-29","2010-06-30"))),
low="white", high="blue") +
scale_shape_discrete(name="") +
opts(legend.position="none")
print(p)
you can do that by preparing color by yourself before calling ggplot2.
Here is an example:
data$sdt <- rescale(as.numeric(as.Date(data$dt))) # data scaled [0, 1]
cols <- c("red", "blue") # colour of gradients for each group
# here the color for each value are calculated
data$col <- ddply(data, .(grp), function(x)
data.frame(col=apply(colorRamp(c("white", cols[as.numeric(x$grp)[1]]))(x$sdt),
1,function(x)rgb(x[1],x[2],x[3], max=255)))
)$col
p <- ggplot(data, aes(x,y, shape=grp, colour=col)) +
geom_jitter(size=4, alpha=0.75) +
scale_colour_identity() + # use identity colour scale
scale_shape_discrete(name="") +
opts(legend.position="none")
print(p)