Wrapping the text of the legend according to the plot window

Question

I use ggplot to chart some data, and I noticed that the text of the legends is very long and not suitable for the window.

+ opts(legend.position = 'bottom', legend.direction = 'horizontal', size=0.1) + guides(colour = guide_legend(nrow = 3), size=1) 

Is there a ggplot option to wrap the legend text according to the window.

Answer 1

As far as I know, so I applied a workaround using strwidth() , which calculates the width of the text in the base graphic.

 title <- "This is a really excessively wide title for a plot, especially since it probably won't fit" 

Use par("din") to get the width of the device, and strwidth () `to calculate the text size:

 par("din")[1] [1] 8.819444 strwidth(title, units="inches") [1] 11.47222 

Use it in function and graphics:

 wrapTitle <- function(x, width=par("din")[1]){ xx <- strwrap(x, width=0.8 * nchar(x) * width / strwidth(x, units="inches")) paste(xx, collapse="\n") } wrapTitle(title) [1] "This is a really excessively wide title for a plot, especially since it\nprobably won't fit, meaning we somehow have to wrap it" 

Plot:

 ggplot(mtcars, aes(wt, mpg)) + geom_point() + opts(title=wrapTitle(title)) 

---

If you want to save the graph to a file, you can replace par("din") with the actual saved graph sizes.