I want to use the title "CO2 emissions in wetlands" in a plot in R, whereas the 2 in CO2 is in subscript, and the value for the region (here: "wetlands") is contained in a variable named "region".
region = "wetlands"
plot (1, 1, main=expression(CO[2]~paste(" emissions in ", region)))
The problem is, that not the value of the variable is pasted, but the name of the variable. This gives "CO2 emissions in region" instead of "CO2 emissions in wetlands". I also tried:
region="wetlands"
plot (1,1,main=paste(expression(CO[2]), "emissions in", region))
But the subscript is not done here, and the title is: "CO[2] emissions in wetlands".
Is it somehow possible to get values of variables into expression?
Thanks for your help,
Sven
There is no need to use paste() in producing an expression for plothmath-style annotation. This works just fine:
region <- "foo"
plot (1, 1, main = bquote(CO[2] ~ "emissions in" ~ .(region)))
giving:
Using paste() just gets in the way.
Nb: You have to quote "in" because the parser grabs it as a key part of R syntax otherwise.
You can use substitute:
mn <- substitute(CO[2]~ "emissions in" ~ region, list(region="wetlands") )
plot(1, 1, main=mn )
From the ?substitute help file:
The typical use of substitute is to create informative labels for
data sets and plots. The myplot example below shows a simple use of
this facility. It uses the functions deparse and substitute to create
labels for a plot which are character string versions of the actual
arguments to the function myplot.
For your case, stolen from one of the answers at the duplicated link:
x <- "OberKrain"
plot(1:10, 1:10, main = bquote(paste(CO[2], " in ", .(x))))
Related
I want to add a label with mathematical notations and a number reference to my plot. I tried the expression function and the paste function, but I failed to include what I want to write in my plot.
Here is a easy version of my question:
plot(NA,xlim = c(0, 5), ylim = c(0,5))
a = 5
At point (1,1), I want to add a label γ=5 on the plot. Here is what I tried:
text(1,1,expression(paste(gamma, "=", a)))
But the plot shows that γ=a.
I am wondering how I can include a number reference in the combination of expression and paste function.
Thank you!
users
thanks to the reply of #McQueenDon on r-nabble
http://r.789695.n4.nabble.com/boxplot-with-x-axis-time-td4686787.html#a4687746
I managed to produce a boxplot::base of a single variable with the x-axis correctly formatted and spaced for the date of acquisition.
What if I would like to produce it with bwplot::lattice? I need this because I would like also to use a conditional factor.
Here you are a reproducible example (thanks again to #McQueenDon )
data(iris)
pippo= stack(iris[,-5])
pippo$date= rep(c("2013/01/29", "2013/03/01", "2013/11/01",
"2013/12/01", "2014/02/01", "2014/07/02"), 100)
pippo$date= as.Date(pippo$date)
boxplot(pippo$values ~ pippo$date) ## NOT exactly what I want
bx<- boxplot(pippo$values ~ pippo$date, plot= F)
bxp(bx, at=sort(unique(pippo$date))) # this is what I was looking for !
require(lattice)
bwplot(values~date, pippo, horizontal=F) #dates looks not correctly spaced even though they are correctly ordered and formatted
# finally I would like to condition to the 'ind' variable
bwplot(values~date| ind, pippo, horizontal=F, layout= c(2,2))
Thanks
Giuseppe
How about
xyplot(values~date| ind, pippo, horizontal=F, layout= c(2,2),
panel=panel.bwplot, box.width=20)
Here we use xyplot with a custom panel= parameter rather than bwplot because bwplot converts the x to a factor first which renumbers all the levels with sequential integers; xyplot does not do this.
If you wanted to label the exact dates, you could try
dts<-unique(pippo$date)
xyplot(values~date| ind, pippo, horizontal=F, layout= c(2,2),
panel=panel.bwplot, box.width=20,
scales=list(x=list(at=dts)))
but that looks quote crowded in this particular example.
Good day!
I am not that familiar to R so I'd be glad to get a little help.
Assume I have the following minimal example:
test <- c(10,20,40,80,80)
avg <- mean(test)
avg <- format(avg,digits=2)
plot(test, xlab="x", ylab="y", pch = 4)
legend("topleft", legend= c("Average: ", avg))
I'd like to write x̄ instead of "average" - wonder if this is event possible as it's not a regular symbol - merely a combination of two (letter plus overline).
The other thing I'd like to get rid of is the line break after the word "Average (see arrow in graphic below):
There are two issues here. The first is that this is handled using ?plotmath in R. The operator you are looking for is bar(). This is not a function but markup that plotmath understands.
The second is that you need an expression in which avg is converted to its value. You need an expression because that is what plotmath works with. There are several solutions to this problem, but the one I use below is bquote(). You provide it an expression and anything wrapped in .( ) will be converted its value by evaluating the thing inside the .( ).
Here is your code and a suitably modified legend() call:
test <- c(10,20,40,80,80)
avg <- mean(test)
avg <- format(avg,digits=2)
plot(test, xlab="x", ylab="y", pch = 4)
legend("topleft", legend = bquote(bar(x)*":" ~ .(avg)))
Do note that this will insert exactly what is in avg. You may need to do
avg <- round(avg)
or some other formatting fix to get something nice and presentable.
I am attempting to plot a graph using the code below:
Require(Hmisc)
Ecdf(ceac_primary,xlab="axis label",xlim=c(5000,50000),q=c(0.9,0.1),
ylab="Probability of Success",main="CEAC")
Where ceac_primary is a data frame with 1 variable of 90k observations.
When I include the 'xlab="axis label"' I keep getting the following error:
Error in Ecdf.default(v, group = group, weights = weights, normwt = normwt, :
formal argument "xlab" matched by multiple actual arguments
However if I exclude the x axis label part of the code, it plots the graph fine.
Is this a known problem, and if so, are there alternative ways to plot an x axis label?
Thanks
Digging around in the source code for Ecdf.data.frame (the method that is called when passing a data.frame to Ecdf), it looks like that function creates an object that is later passed to the xlab argument. Therefore, xlab is not expected as a user-supplied argument when running Ecdf with a data.frame. Here's the code that creates the object lab that gets passed to xlab within Ecdf.data.frame:
lab <- if (vnames == "names")
nam[j]
else label(v, units = TRUE, plot = TRUE, default = nam[j])
Then Ecdf is called with xlab = lab, but also any arguments in the elipses of Ecdf.data.frame are also passed to Ecdf. Since xlab is not a formal argument of Ecdf.data.frame, this is why you get your error.
To get around it, try either of the following:
Convert your data.frame to a vector of the appropriate class (numeric, I presume), and then run
Ecdf(ceac_primary_Vec, xlab = "axis label")
Or, you can create a label for the one column in your data.frame using the label function in the Hmisc package. If that column is called myCol, you can run
label(ceac_primary$myCol) <- "axis label"
Ecdf(ceac_primary)
And that should get your axis label printing correctly.
Say, I have a variable rv which has some numerical value. Now, I want to plot the value of this variable on a base plot but preceded by a nicely formatted symbol e.g., r subscript m, using expression. To write on the plot I use mtext.
However, what I get is either the value of the variable, but no nicely formatted symbol (left annotation), or a nicely formatted symbol, but not the value of the variable, but the variable name...
I tried to play around with eval, but didn't get what I wanted. Here is my code:
plot(1:10, rep(10,10), ylim=c(0,12))
rv <- 0.43
#left annotation:
mtext(paste(expression(italic(r[M])), " = ", rv), side = 1, line = -1.5, adj = 0.1)
#right annotation:
mtext(expression(paste(italic(r[M]), " = ", rv)), side = 1, line = -1.5, adj = 0.9)
This is the result:
How do i get both, nice format and value of the variable? Thanks.
btw: I know that I can get it, if I use two times mtext and play around with adj and stuff. But I would really like to get it in one call or without playing around with the position of two annotations.
The bquote function will create an expression and alow substitution of values using .(var) syntax. for your case do something like:
text( 5,1, bquote( italic(r[M]) == .(rv) ) )
Just combine what you have and plot two pieces, joined by using adj:
R> plot(1:10, rep(10,10), ylim=c(0,12))
R> text(2,12, expression(paste(italic(r[M]))), adj=1)
R> text(2,12, paste("=", rv), adj=0)