Titles (ggplot2)

Problem

You want to set the title of your graph.

Solution

An example graph without a title:

  1. library(ggplot2)
  2. bp <- ggplot(PlantGrowth, aes(x=group, y=weight)) + geom_boxplot()
  3. bp

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With a title:

  1. bp + ggtitle("Plant growth")
  2. ## Equivalent to
  3. # bp + labs(title="Plant growth")
  5. # If the title is long, it can be split into multiple lines with \n
  6. bp + ggtitle("Plant growth with\ndifferent treatments")
  8. # Reduce line spacing and use bold text
  9. bp + ggtitle("Plant growth with\ndifferent treatments") + 
  10.      theme(plot.title = element_text(lineheight=.8, face="bold"))

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