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rggplot2mathematical-expressions

Mixing expression, plain text and newline in ggplot2 expression

I am trying to create some labels/stickers using ggplot2. I am pulling the text for the labels from a source and tyring to plot. I am able to do that as follows: 

labtxt1 <- c("This text should be bold", "This text should also be bold", "Another text to be bold")
labtxt1 <- strwrap(labtxt1, width = 20)

labtxt2 <- c("This text should not be bold", "This text should also not be bold", "Another text to be plain")
labtxt2 <- strwrap(labtxt2, width = 20)

library(ggplot2)
library(Hmisc)

labtxt <- c(labtxt1, labtxt2)
labtxt <- paste(labtxt, collapse = "\n", sep = "")
labtxt <- escapeRegex(labtxt)

ggplot(x=1, y = 1) + 
  annotate("text", x = 0.5, y = 0.5, 
           label = labtxt,
           colour = "red", parse = F, lineheight = 0.8)

enter image description here

How to now make the text in labtxt1 to bold, along with the text in labtxt2 as plain maintaining the justification and linewidth?

I have tried with expression with \n, which messes up the justification, and with atop, but which messes up the linewidth.

If I try to annotate separately, then positioning is difficult as the lenght of labtxt1 and labtxt2 varies in for different labels/stickers.

How to get the desired result?

Solution

  • You could wrap the text in an invisible table,

    library(ggplot2)
library(gridExtra)

label <- "plain text\nbold('bold line')\nitalic('italic line')\nplain again"
disect <- strsplit(label, "\\n")[[1]]

mytheme <- ttheme_minimal(core = list(fg_params = list(parse=TRUE, col="red",
                                                       hjust=0, x=0.1)))
tg <- tableGrob(as.matrix(disect), theme=mytheme)

ggplot(x=1, y = 1) + 
  annotation_custom(tg)