I have a ggplot where I have used expression(phantom(x) >=80) in the label text to get a proper greater-than-or-equal symbol.
However I also need to have (N=...) immediately underneath:
require(ggplot2)
.d <- data.frame(a = letters[1:6], y = 1:6)
labs <- c("0-9\n(N=10)","10-29\n(N=10)","30-49\n(N=10)", +
"50-64\n(N=10)","65-79\n(N=10)", expression(phantom(x) >=80))
ggplot(.d, aes(x=a,y=y)) + geom_point() +
scale_x_discrete(labels = labs)
How can I combine the expression() with the escape \n ?
As #otsaw said in his answer to your earlier question, plotmath (and therefore expression) doesn't allow linebreaks.
However, as a hack, you can use atop to let ≥80 appears on top of (N=10). But as you will soon see it doesn't match with the other labels:
labs <- c("0-9\n(N=10)","10-29\n(N=10)","30-49\n(N=10)",
"50-64\n(N=10)","65-79\n(N=10)",
expression(atop(phantom(x) >=80, (N==10))))
So, as a further hack, you can pass the other labels as expressions:
labs <- c(expression(atop(0-9,(N==10))),expression(atop(10-29,(N==10))),
expression(atop(30-49,(N==10))), expression(atop(50-64,(N==10))),
expression(atop(65-79,(N==10))), expression(atop(phantom(x) >=80, (N==10))))
But of course you have #otsaw solution (using Unicode) that is considerably less wordy:
labs <- c("0-9\n(N=10)","10-29\n(N=10)","30-49\n(N=10)",
"50-64\n(N=10)","65-79\n(N=10)",
"\u2265 80\n(N=10)")
Another approach would be to use the recently archived tikzDevice. This creates the plots as tikz which are latex friendly format.
This will allow you to pass any latex expression as a character string to your labels.
It has the added benefit that you can compile the documents with the same preamble as your whole document so that the fonts etc are consistent.
All this can be automated using knitr using opts_chunk$set(dev = 'tikz')
Related
If I want to use paste0 inside expression to label the x-axis, it's not working as intended. But paste works.
library(ggplot2)
ggplot(mtcars, aes(mpg, disp)) +
geom_point() +
labs(
x = expression(paste0("It's","mpg")^("paste0 is not working")),
y = expression(paste("It's ", "disp")^("paste is working")), # had to give extra space
)
Please Note that
I have used paste0 in x-axis, which is not showing as intended
used paste in y-axis which is working, but had to give extra space to separate It's and disp, which should be the default behavior of paste (AFAIK). But that default behavior is not working inside the expression.
Also same happens with base-plot
plot(mtcars$disp ~ mtcars$mpg,
xlab = expression(paste0("mpg")^("paste0 is not working")),
ylab = expression(paste("disp")^("paste is working"))
)
Can anyone please break this out for me,
why paste0 is not working?
and also why pastes default behavior is not preserved here??
What's going on here?
Thanks.
It seems you can only use the operations listed in ?plotmath.
https://stat.ethz.ch/R-manual/R-devel/library/grDevices/html/plotmath.html
paste is there, but paste0 is not.
Also, the function features are not equivalent to the R's functions of the same name.
Is there a way to force an automatic line break in the ggtitle command?
As part of a shiny application I use different plots with an input variable for the title.
Unfortunately, some of these variable values are too long to be displayed.
I came across one possibility by inserting \n (or a line break) manually in advance (Details here: Improve editing of multiline title in ggplot that uses \n and extends far to the right). There, something like ggtitle(paste("", title, "", sep = "\n")) would be suggested.
Since including \n would be error prone as well as not flexible for different plot sizes I´m looking for another possibility.
Here is an minimal working example (adapted from lawyeR question linked above):
DF <- data.frame(x = rnorm(400))
title_example <- "This is a very long title describing the plot in its details. The title should be fitted to a graph, which is itself not restricted by its size."
plot <- ggplot(DF, aes(x = x)) + geom_histogram() +
ggtitle(title_example)
You can find a image here: https://i.stack.imgur.com/6MMKF.jpg
Do you have an idea how to e.g. adapt the sep = operator to break lines automatically or are there maybe packages/ workarounds? Thanks!
The ggtext package's text elements could help solve this. element_textbox_simple() automatically wraps the text inside. Try resizing the graphics device window, it adapts!
library(ggplot2)
library(ggtext)
DF <- data.frame(x = rnorm(400))
title_example <- "This is a very long title describing the plot in its details. The title should be fitted to a graph, which is itself not restricted by its size."
ggplot(DF, aes(x = x)) + geom_histogram() +
ggtitle(title_example) +
theme(plot.title = element_textbox_simple())
#> `stat_bin()` using `bins = 30`. Pick better value with `binwidth`.
I would like to add LaTeX typesetting to elements of plots in R (e.g: the title, axis labels, annotations, etc.) using either the combination of base/lattice or with ggplot2.
Questions:
Is there a way to get LaTeX into plots using these packages, and if so, how is it done?
If not, are there additional packages needed to accomplish this.
For example, in Python matplotlib compiles LaTeX via the text.usetex packages as discussed here: http://www.scipy.org/Cookbook/Matplotlib/UsingTex
Is there a similar process by which such plots can be generated in R?
The CRAN package latex2exp contains a TeX function that translate LaTeX formulas to R's plotmath expressions. You can use it anywhere you could enter mathematical annotations, such as axis labels, legend labels, and general text.
For example:
x <- seq(0, 4, length.out=100)
alpha <- 1:5
plot(x, xlim=c(0, 4), ylim=c(0, 10),
xlab='x', ylab=TeX(r'($\alpha x^\alpha$, where $\alpha \in \{1 \ldots 5\}$)'),
type='n', main=TeX(r'(Using $\LaTeX$ for plotting in base graphics!)', bold=TRUE))
for (a in alpha) {
lines(x, a*x^a, col=a)
}
legend('topleft',
legend=TeX(sprintf(r'($\alpha = %d$)', alpha)),
lwd=1,
col=alpha)
produces this plot.
Here's an example using ggplot2:
q <- qplot(cty, hwy, data = mpg, colour = displ)
q + xlab(expression(beta +frac(miles, gallon)))
As stolen from here, the following command correctly uses LaTeX to draw the title:
plot(1, main=expression(beta[1]))
See ?plotmath for more details.
You can generate tikz code from R:
http://r-forge.r-project.org/projects/tikzdevice/
Here's something from my own Lab Reports.
tickzDevice exports tikz images for LaTeX
Note, that in certain cases "\\" becomes "\" and "$" becomes "$\" as in the following R code: "$z\\frac{a}{b}$" -> "$\z\frac{a}{b}$\"
Also xtable exports tables to latex code
The code:
library(reshape2)
library(plyr)
library(ggplot2)
library(systemfit)
library(xtable)
require(graphics)
require(tikzDevice)
setwd("~/DataFolder/")
Lab5p9 <- read.csv (file="~/DataFolder/Lab5part9.csv", comment.char="#")
AR <- subset(Lab5p9,Region == "Forward.Active")
# make sure the data names aren't already in latex format, it interferes with the ggplot ~ # tikzDecice combo
colnames(AR) <- c("$V_{BB}[V]$", "$V_{RB}[V]$" , "$V_{RC}[V]$" , "$I_B[\\mu A]$" , "IC" , "$V_{BE}[V]$" , "$V_{CE}[V]$" , "beta" , "$I_E[mA]$")
# make sure the working directory is where you want your tikz file to go
setwd("~/TexImageFolder/")
# export plot as a .tex file in the tikz format
tikz('betaplot.tex', width = 6,height = 3.5,pointsize = 12) #define plot name size and font size
#define plot margin widths
par(mar=c(3,5,3,5)) # The syntax is mar=c(bottom, left, top, right).
ggplot(AR, aes(x=IC, y=beta)) + # define data set
geom_point(colour="#000000",size=1.5) + # use points
geom_smooth(method=loess,span=2) + # use smooth
theme_bw() + # no grey background
xlab("$I_C[mA]$") + # x axis label in latex format
ylab ("$\\beta$") + # y axis label in latex format
theme(axis.title.y=element_text(angle=0)) + # rotate y axis label
theme(axis.title.x=element_text(vjust=-0.5)) + # adjust x axis label down
theme(axis.title.y=element_text(hjust=-0.5)) + # adjust y axis lable left
theme(panel.grid.major=element_line(colour="grey80", size=0.5)) +# major grid color
theme(panel.grid.minor=element_line(colour="grey95", size=0.4)) +# minor grid color
scale_x_continuous(minor_breaks=seq(0,9.5,by=0.5)) +# adjust x minor grid spacing
scale_y_continuous(minor_breaks=seq(170,185,by=0.5)) + # adjust y minor grid spacing
theme(panel.border=element_rect(colour="black",size=.75))# border color and size
dev.off() # export file and exit tikzDevice function
Here's a cool function that lets you use the plotmath functionality, but with the expressions stored as objects of the character mode. This lets you manipulate them programmatically using paste or regular expression functions. I don't use ggplot, but it should work there as well:
express <- function(char.expressions){
return(parse(text=paste(char.expressions,collapse=";")))
}
par(mar=c(6,6,1,1))
plot(0,0,xlim=sym(),ylim=sym(),xaxt="n",yaxt="n",mgp=c(4,0.2,0),
xlab="axis(1,(-9:9)/10,tick.labels,las=2,cex.axis=0.8)",
ylab="axis(2,(-9:9)/10,express(tick.labels),las=1,cex.axis=0.8)")
tick.labels <- paste("x >=",(-9:9)/10)
# this is what you get if you just use tick.labels the regular way:
axis(1,(-9:9)/10,tick.labels,las=2,cex.axis=0.8)
# but if you express() them... voila!
axis(2,(-9:9)/10,express(tick.labels),las=1,cex.axis=0.8)
I did this a few years ago by outputting to a .fig format instead of directly to a .pdf; you write the titles including the latex code and use fig2ps or fig2pdf to create the final graphic file. The setup I had to do this broke with R 2.5; if I had to do it again I'd look into tikz instead, but am including this here anyway as another potential option.
My notes on how I did it using Sweave are here: http://www.stat.umn.edu/~arendahl/computing
I just have a workaround. One may first generate an eps file, then convert it back to pgf using the tool eps2pgf. See http://www.texample.net/tikz/examples/eps2pgf/
h <- rnorm(mean = 5, sd = 1, n = 1000)
hist(h, main = expression(paste("Sampled values, ", mu, "=5, ", sigma,
"=1")))
Taken from a very help article here https://stats.idre.ucla.edu/r/codefragments/greek_letters/
You can use the following, for example:
title(sub=TeX(sprintf(paste("Some latex symbols are ", r'(\lambda)', "and", r'(\alpha)'))))
Just remember to enclose LaTeX expressions in paste() using r'()'
You can also add named objects in the paste() function. E.g.,
lambda_variable <- 3
title(sub=TeX(sprintf(paste(r'(\lambda=)', lambda_variable))))
Not sure if there are better ways to do this, but the above worked for me :)
How to show $\{ X_t \}$ of Latex in the title of a plot of R?
For example
plot(slot(x,"GRID"),slot(x,"PATH"),type="l", xlab="Time t",ylab="X",
main=paste("Simulation of \{X_t\}"))
Thanks!
Assuming you will provide meaningful arguments for the slot expressions, then I think there is a reasonable chance that this is what you want:
plot(1:10,1:10,type="l", xlab="Time t",ylab="X",
main=expression("Simulation of {"*X[t]*"}"))
This is a plotmath expression that presents "t" as a subscript of "X" and that expression is enclosed in curley braces. If I have misread your request, then note that the "*" character is a separator in the plotmath syntax and the braces are simply characters than can be deleted. (The LaTeX expressions don't make a lot of sense to those of us who just use the plotmath syntax, so describing what you want in prose or mathematical jargon would work better for any clarifications.)
To have R emulate LaTeX typesetting, see the examples and methods described in ?plotmath.
To actually have LaTeX typeset your plot text, use the tikz() graphics device provided by the tikzDevice package.
The group() plotmath function can be used to formalise DWin's answer. This solution has the advantage (IMHO) of not using strings as part of the expression. Instead we use the ~ operator to add spacing (whitespace is ignored).
plot(1:10, 1:10, type = "l", xlab = "Time t", ylab = "X",
main=expression(Simulation ~ of ~ group("{", X[t], "}")))
The bgroup() plotmath function provides scalable delimiters but is used in the same manner as the example code above.
Edit (In response to ran2's comment):
The same approaches can be used in ggplot and lattice, using the power of plotmath, just as with base graphics. E.g.
require(ggplot2)
df <- data.frame(A = 1:10, B = 1:10)
qplot(A, B, data = df,
main = expression(Simulation ~ of ~ group("{", X[t], "}")))
I would like to add LaTeX typesetting to elements of plots in R (e.g: the title, axis labels, annotations, etc.) using either the combination of base/lattice or with ggplot2.
Questions:
Is there a way to get LaTeX into plots using these packages, and if so, how is it done?
If not, are there additional packages needed to accomplish this.
For example, in Python matplotlib compiles LaTeX via the text.usetex packages as discussed here: http://www.scipy.org/Cookbook/Matplotlib/UsingTex
Is there a similar process by which such plots can be generated in R?
The CRAN package latex2exp contains a TeX function that translate LaTeX formulas to R's plotmath expressions. You can use it anywhere you could enter mathematical annotations, such as axis labels, legend labels, and general text.
For example:
x <- seq(0, 4, length.out=100)
alpha <- 1:5
plot(x, xlim=c(0, 4), ylim=c(0, 10),
xlab='x', ylab=TeX(r'($\alpha x^\alpha$, where $\alpha \in \{1 \ldots 5\}$)'),
type='n', main=TeX(r'(Using $\LaTeX$ for plotting in base graphics!)', bold=TRUE))
for (a in alpha) {
lines(x, a*x^a, col=a)
}
legend('topleft',
legend=TeX(sprintf(r'($\alpha = %d$)', alpha)),
lwd=1,
col=alpha)
produces this plot.
Here's an example using ggplot2:
q <- qplot(cty, hwy, data = mpg, colour = displ)
q + xlab(expression(beta +frac(miles, gallon)))
As stolen from here, the following command correctly uses LaTeX to draw the title:
plot(1, main=expression(beta[1]))
See ?plotmath for more details.
You can generate tikz code from R:
http://r-forge.r-project.org/projects/tikzdevice/
Here's something from my own Lab Reports.
tickzDevice exports tikz images for LaTeX
Note, that in certain cases "\\" becomes "\" and "$" becomes "$\" as in the following R code: "$z\\frac{a}{b}$" -> "$\z\frac{a}{b}$\"
Also xtable exports tables to latex code
The code:
library(reshape2)
library(plyr)
library(ggplot2)
library(systemfit)
library(xtable)
require(graphics)
require(tikzDevice)
setwd("~/DataFolder/")
Lab5p9 <- read.csv (file="~/DataFolder/Lab5part9.csv", comment.char="#")
AR <- subset(Lab5p9,Region == "Forward.Active")
# make sure the data names aren't already in latex format, it interferes with the ggplot ~ # tikzDecice combo
colnames(AR) <- c("$V_{BB}[V]$", "$V_{RB}[V]$" , "$V_{RC}[V]$" , "$I_B[\\mu A]$" , "IC" , "$V_{BE}[V]$" , "$V_{CE}[V]$" , "beta" , "$I_E[mA]$")
# make sure the working directory is where you want your tikz file to go
setwd("~/TexImageFolder/")
# export plot as a .tex file in the tikz format
tikz('betaplot.tex', width = 6,height = 3.5,pointsize = 12) #define plot name size and font size
#define plot margin widths
par(mar=c(3,5,3,5)) # The syntax is mar=c(bottom, left, top, right).
ggplot(AR, aes(x=IC, y=beta)) + # define data set
geom_point(colour="#000000",size=1.5) + # use points
geom_smooth(method=loess,span=2) + # use smooth
theme_bw() + # no grey background
xlab("$I_C[mA]$") + # x axis label in latex format
ylab ("$\\beta$") + # y axis label in latex format
theme(axis.title.y=element_text(angle=0)) + # rotate y axis label
theme(axis.title.x=element_text(vjust=-0.5)) + # adjust x axis label down
theme(axis.title.y=element_text(hjust=-0.5)) + # adjust y axis lable left
theme(panel.grid.major=element_line(colour="grey80", size=0.5)) +# major grid color
theme(panel.grid.minor=element_line(colour="grey95", size=0.4)) +# minor grid color
scale_x_continuous(minor_breaks=seq(0,9.5,by=0.5)) +# adjust x minor grid spacing
scale_y_continuous(minor_breaks=seq(170,185,by=0.5)) + # adjust y minor grid spacing
theme(panel.border=element_rect(colour="black",size=.75))# border color and size
dev.off() # export file and exit tikzDevice function
Here's a cool function that lets you use the plotmath functionality, but with the expressions stored as objects of the character mode. This lets you manipulate them programmatically using paste or regular expression functions. I don't use ggplot, but it should work there as well:
express <- function(char.expressions){
return(parse(text=paste(char.expressions,collapse=";")))
}
par(mar=c(6,6,1,1))
plot(0,0,xlim=sym(),ylim=sym(),xaxt="n",yaxt="n",mgp=c(4,0.2,0),
xlab="axis(1,(-9:9)/10,tick.labels,las=2,cex.axis=0.8)",
ylab="axis(2,(-9:9)/10,express(tick.labels),las=1,cex.axis=0.8)")
tick.labels <- paste("x >=",(-9:9)/10)
# this is what you get if you just use tick.labels the regular way:
axis(1,(-9:9)/10,tick.labels,las=2,cex.axis=0.8)
# but if you express() them... voila!
axis(2,(-9:9)/10,express(tick.labels),las=1,cex.axis=0.8)
I did this a few years ago by outputting to a .fig format instead of directly to a .pdf; you write the titles including the latex code and use fig2ps or fig2pdf to create the final graphic file. The setup I had to do this broke with R 2.5; if I had to do it again I'd look into tikz instead, but am including this here anyway as another potential option.
My notes on how I did it using Sweave are here: http://www.stat.umn.edu/~arendahl/computing
I just have a workaround. One may first generate an eps file, then convert it back to pgf using the tool eps2pgf. See http://www.texample.net/tikz/examples/eps2pgf/
h <- rnorm(mean = 5, sd = 1, n = 1000)
hist(h, main = expression(paste("Sampled values, ", mu, "=5, ", sigma,
"=1")))
Taken from a very help article here https://stats.idre.ucla.edu/r/codefragments/greek_letters/
You can use the following, for example:
title(sub=TeX(sprintf(paste("Some latex symbols are ", r'(\lambda)', "and", r'(\alpha)'))))
Just remember to enclose LaTeX expressions in paste() using r'()'
You can also add named objects in the paste() function. E.g.,
lambda_variable <- 3
title(sub=TeX(sprintf(paste(r'(\lambda=)', lambda_variable))))
Not sure if there are better ways to do this, but the above worked for me :)