Convert HTML to R Markdown - r

Question

Is there a way to convert an html file, such as https://cran.r-project.org/web/packages/tidytext/vignettes/tidytext.html, and convert it to an executable R Markdown file (rmd)?

Answer 1

Here is the solution I use:
convert .html to .md :
pandoc ./test.html -o test.md
rename .md to .rmd
mv test.md test.rmd
post-process the code to organize chunk and paragraphs
# chunks r marker: replace ' {\.sourceCode \.r}' by '{r}'
sed -i 's/ {\.sourceCode \.r/{r/' test.rmd
# delete lines beginning wit ':::'
sed -i '/^:::/d' test.rmd
# delete lines beginning '![](data:image' (html plot)
sed -i '/^\!\[\](data:image/d' test.rmd
# delete paragraph separator lines
sed -i '/^=====/d' test.rmd
sed -i '/^-----/d' test.rmd
# replace paragraph marks
#'[1]{.header-section-number}' by '#'
sed -i 's/\[[0-9]\+\]{\.header-section-number}/#/' test.rmd
#'[1.1]{.header-section-number}' by '##'
sed -i 's/\[[0-9]\+\.[0-9]\+\]{\.header-section-number}/##/' test.rmd
#'[1.1.1]{.header-section-number}' by '###'
sed -i 's/\[[0-9]\+\.[0-9]\+\\.[0-9]\+]{\.header-section-number}/###/' test.rmd
add YAML header
echo "$(echo -e "\n" | cat - test.rmd)" > test.rmd
echo "$(echo '---' | cat - test.rmd)" > test.rmd
echo "$(echo 'title: '\"'test'\" | cat - test.rmd)" > test.rmd
echo "$(echo '---' | cat - test.rmd)" > test.rmd
Of course you can have these lines in a .sh to simplify the task

Answer 2

If a markdown file (.md) is sufficient then download and install pandoc if you don't already have it. Then run this from the commmand line or use system("pandoc ...") or shell("pandoc ...") from within R.
pandoc https://cran.r-project.org/web/packages/tidytext/vignettes/tidytext.html -o out.md
For a particular file, it would be possible to post-process the source code and output sections but would represent some additional effort, possibly substantial.

Answer 3

In short, no.
The pandoc binary is almost pure awesomeness, and I use it eg to convert the html output from an Rd file back into markdown (to be included in other markdown documents).
But that uses pandoc for what it knows: convert from markdown to html etc. pandoc itself knows nothing about R. So apart from the metaphysical difficulty of getting the code back from the output it created, you have a tool mismatch.
So in some: you probably want the original source code as you cannot recreate Rmd from the html output it produces.

Answer 4

You can get a 98% result by:
Opening a new rmarkdown file (in RStudio v 1.4+),
Click on the "Switch to visual markdown editor" button*,
Select and copy the html output from the browser
Paste into your rmarkdown file.
To get the last 2%, you will want ensure R code chunks are recognised:
Click on the "Switch to source editor" button (same button as above).
Find and replace <!-- --> with ```{r} and after finish the code chunks with ```
And ensure data is available as required by the code. Good luck!
*To switch into visual mode for a markdown document, use the button with the compass icon at the top-right of the editor toolbar - described here: https://blog.rstudio.com/2020/09/30/rstudio-v1-4-preview-visual-markdown-editing/

Answer 5

:~$ ## convert .html to .md :
:~$ pandoc Assessment-Week2B.html -o Assessment-Week2B.md
:~$
:~$ ## rename .md to .rmd
:~$ mv Assessment-Week2B.md Assessment-Week2B.rmd
:~$
:~$ ## edit via RStudio
:~$ rstudio Assessment-Week2B.Rmd
Tried to modify via terminal as below short MV, but modify via RStudio will be easier.
Convert HTML to R Markdown (Part 1)
Convert HTML to R Markdown (Part 2)