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rknitrrstudior-markdownslidify

two-column layouts in RStudio presentations/slidify/pandoc

I'm trying to come up with a good system for generating slides and accompanying handouts. The ideal system would have the following properties:

  • beautiful in both presentation (PDF/HTML) and handout (PDF) layouts (handouts should have room for taking notes)
  • embedded R chunks, figures, other JPG/PNG pictures, etc.
  • easy to compose
  • build using command-line tools
  • bibliography support
  • pandoc slide separator format (automatically generate a new slide after headers of a specified level) is preferred
  • I can live with a little bit of additional processing (e.g. via sed), but would prefer not to write a huge infrastructure
  • two-column layouts: there is a SO post on how to get multi-column slides from pandoc, but it is LaTeX- rather than HTML-oriented.
  • ability to adjust sizes of embedded images (other than R-generated figures) and column widths on the fly

Here's what I've discovered so far about the various options:

  • Slidify:
    • doesn't do pandoc slide separator format, although there is a workaround
    • the suggestion for creating handouts is to print to PDF; I'd like to leave room for notes etc. (I could probably figure out a way to do that using something like PDFtk or psnup ...)
  • RStudio presentations (.Rpres files):
    • does lots of things nicely, including multi-columns with specified widths
    • doesn't support pandoc slide separator format
    • I can't figure out what's going on under the hood. There is RStudio documentation that describes the translation process for regular HTML, but it doesn't seem to cover the R presentation format (which isn't quite the same). (I have previously invested some effort in figuring out how to get RStudio-like output via pandoc ...), which means I can't generate slides etc. from the command line.
  • RStudio's Development Version (as of March 2014) comes bundled with Pandoc and version 2 of rmarkdown. It addresses many of the above issues with the .Rpres format.
  • pandoc: may be the only markdown-translator that has features such as footnotes, bibliography support, etc.. I can also use pandoc to generate LaTeX using the tufte-handout class, which meets my criteria of beauty.
    • Unfortunately, it seems not to have built-in two-column format support. Yihui Xie's HTML5 example doesn't show any two-column examples, and it claims (on slide 5) that clicking the "Knit HTML" button in RStudio is equivalent to pandoc -s -S -i -t dzslides --mathjax knitr-slides.md -o knitr-slides.html, but it doesn't seem to be ...
  • LaTeX/beamer: I could simply compose in Rnw (knitr-dialect Sweave) rather than R markdown to begin with. This would give me ultimate flexibility ...
    • despite many years of LaTeX use I do find LaTeX composition more of a pain than markdown composition.

After all that, my specific question is: what's the best (easiest) way to generate a two-column layout for HTML output?

Any other advice will also be appreciated.

Solution

  • I now have what I think is a reasonable solution that should apply at least to ioslides-based solutions, and maybe (?) to other HTML5-based formats. Starting here, I added

    <style>
div#before-column p.forceBreak {
    break-before: column;
}
div#after-column p.forceBreak {
    break-after: column;
}
</style>

    to the beginning of my document; then putting <p class="forceBreak"></p> within a slide with {.columns-2} breaks the column at that point, e.g.

    ## Latin hypercube sampling {.columns-2}

- sample evenly, randomly across (potentially many) uncertain parameters

<p class="forceBreak"></p>

![](LHScrop.png)
[User:Saittam, Wikipedia](https://commons.wikimedia.org/wiki/File:LHSsampling.png#/media/File:LHSsampling.png)

    There may be an even better way, but this isn't too painful.

    @ChrisMerkord points out in comments that

    .forceBreak { -webkit-column-break-after: always; break-after: column; }

    worked instead (I haven't tested ...)