rggplot2plotaxis-labels

Wrap long axis labels via labeller=label_wrap in ggplot2


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")

Histogram with long label not wrapped

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


Solution

  • 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))
    

    enter image description here