Wrap long axis labels via labeller=label_wrap in ggplot2

Question

I would like to automatically wrap my labels in ggplot2, i.e. insert line breaks of long labels. Here is written how to write a function (1) for it, but sadly I do not know where to put labeller=label_wrap in my code (2).

(1) function by hadley

label_wrap <- function(variable, value) {   lapply(strwrap(as.character(value), width=25, simplify=FALSE),           paste, collapse="\n") } 

(2) code example

df = data.frame(x = c("label", "long label", "very, very long label"),                  y = c(10, 15, 20))  ggplot(df, aes(x, y)) + geom_bar(stat="identity") 

I'd like to wrap some of the longer labels here.

Answer 1

You don't need the label_wrap function. Instead use the str_wrap function from the stringr package.

You do not provide your df data frame, so I create a simple data frame, one that contains your labels. Then, apply the str_wrap function to the labels.

library(ggplot2) library(stringr)  df = data.frame(x = c("label", "long label", "very, very long label"),                  y = c(10, 15, 20)) df  df$newx = str_wrap(df$x, width = 10) df 

Now to apply the labels to a ggplot chart: The first chart uses the original labels; the second chart uses the modified labels; and for the third chart, the labels are modified in the call to ggplot.

ggplot(df, aes(x, y)) +    xlab("") + ylab("Number of Participants") +   geom_bar(stat = "identity")   ggplot(df, aes(newx, y)) +    xlab("") + ylab("Number of Participants") +   geom_bar(stat = "identity")  ggplot(df, aes(x, y)) +    xlab("") + ylab("Number of Participants") +   geom_bar(stat = "identity") +   scale_x_discrete(labels = function(x) str_wrap(x, width = 10))