How to wrap text in R source with tidy and knitr

Question

I\'m working with knitr lately and while most aspects of that have gone quite smoothly, there\'s one formatting issue with including R code in the finished document that I haven

Answer 1

This answer is a bit late to the party, but I have found that even when I use tidy.opts = list(width.cutoff = 60) in an early chunk (using RStudio and a .Rnw script) and then in each chunk option list I include tidy = TRUE, the overflow of lines still happens. My overflow lines are in sections of code that create ggplot2 plots. Trial and error discovered that if I add a carriage return after the + at the end of a line, I have no overflow problems. The extra line does not show up in the PDF that LaTeX creates.

Answer 2

The other solution is to use strwrap.

> longstr <- "This string will flow off the right side of the page, because tidy doesn't know how to wrap it."
> strwrap(longstr, 70)
[1] "This string will flow off the right side of the page, because tidy" "doesn't know how to wrap it."                                      
> str(strwrap(longstr, 70))
chr [1:2] "This string will flow off the right side of the page, because tidy" "doesn't know how to wrap it."

Unfortunately, I do not know whether this will work with tidy, but it works extremely well with knitr's HTML output.

Answer 3

This is an extremely manual solution, but one which I have used.

You build the string up, using paste0 and that gives tidy a chance to split it.

longstr <- paste0("This string will flow off the right side"," of the page, because tidy doesn't know how to wrap it.")