Comment out text in R Markdown (Rmd file)

Question

In an R Markdown (.Rmd) file, how do you comment out unused text? I'm not referring to the text in the R code chunk, but the general texts, like % in LaTex for example.

[Was initially closed as duplicate](https://stackoverflow.com/questions/4823468/comments-in-markdown); re-opening since Rmarkdown can potentially provide alternative options not supported by markdown. — baptiste, Oct 23 '17 at 01:42
This question is widely answered here: https://stackoverflow.com/questions/4823468/comments-in-markdown — Chema_arguez, Jan 30 '23 at 09:01

score 201 · Accepted Answer · answered Jun 11 '13 at 14:50

201

I think you should be able to use regular html comments:

<!-- regular html comment -->

Does this work for you?

answered Jun 11 '13 at 14:50

user1981275

13,002
8
72
101

7

oddly, inline r code within those html comments tries to evaluate. e.g., `<-- Some text with \`r mean(x)\` inline code -->` can result in 'blah not Found' errors on Knit due to the inline code being unexpectedly evaluated. – Brian D May 01 '19 at 14:39
I think I remember seeing Yihui Xie mention that having knitr recognize the comment characters would be too difficult because knitr is not responsible for rendering the document into html or pdf. I think the HTML comment characters are only dealt with by pandoc/rmarkdown after knitting. – randy Jul 12 '19 at 21:57

score 37 · Answer 2 · answered Oct 23 '17 at 01:45

Extra yaml blocks can be used anywhere inside the document, and commented out with #

---
title: "Untitled"
output: html_document
---

No comment.

---
# here's a comment
# ```{r}
# x = pi
# ```
---

Note however that this does not prevent knitr from evaluating inline r code.

z0nam · Answer 3 · 2020-03-10T06:10:53.173

24

After drag the lines you want to make comment, press SHIFT+CMD+C (macOS), SHIFT+CTRL+C (Windows). This is the shortcut of R Markdown editor (R Studio) to comment out.

edited Mar 10 '20 at 06:10

answered Apr 24 '19 at 02:18

z0nam

525
7
19

11

For me it was Ctrl+ Shift + C. Thanks! – Evan Rosica Aug 16 '19 at 06:13
2

I'm running Windows 10, and for me it was also Ctrl+Shift+C. Thanks! – HelloGoodbye Sep 24 '19 at 20:41
2

@EvanRosica, HelloGoodbye, Thank you for your information, I edited my answer to add windows shortcut explicitly. – z0nam Mar 10 '20 at 06:12
This may work for people who use RStudio, but not for those who write Rmarkdown code with other editors or IDEs - for instance, I use Notepad++, and this shortcut of course does not help there. – Stephan Kolassa Feb 23 '23 at 15:50

score 0 · Answer 4 · answered May 13 '21 at 07:57

0

You can always turn off code by putting it within an if(F){} statement.

answered May 13 '21 at 07:57

chriselbers

1
2

score 0 · Answer 5 · edited Jun 13 '23 at 10:41

We can use

# Converted R Markdown code chunk in .Rmd file
    
`r ''````{r stream, eval=FALSE}
strm <- FastqStreamer("a.fastq.gz")
repeat {
  fq <- yield(strm)
  if (length(fq) == 0)
    break
  ## process chunk
}

This is found from a https://github.com/rstudio/rmarkdown-book/blob/main/03-documents.Rmd bookdown which is used we want a code block to not execute while knitting.

Does it solves your problem??? if you have any questions please let me know.

Comment out text in R Markdown (Rmd file)

5 Answers5

Linked