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rpdfencodingplotmath

How do I write a plot containing a symbol to PDF in R?

I want to use the infinity sign on the x-axis of a box plot in R, which I want to write to a PDF file.

I can set the infinity symbol by doing

names(data)[9] <- "∞"

but that gets me encoding errors when trying to write:

conversion failure on '∞' in 'mbcsToSbcs': dot substituted for <...>
Solution

  • You can either use Unicode as in this example: using Unicode 'dingbat-like' glyphs in R graphics, across devices & platforms, especially PDF (infinity is Unicode 8734): in particular, it's possible that simply using a cairoPDF device will make this work. Probably a better idea is to use ?plotmath capabilities (as referenced in ?boxplot under the names argument:

     boxplot(matrix(1:10,ncol=2),names=c("a",expression(infinity)))