### Aspirational & Useful: deck.rb with RStudio/knitr & Go2Shell

There has been some interest in the recent release of RStudio 0.96 and especially the ability to use combine its knitr Markdown functionality with Pandoc to integrate R and a variety of different documents types.

I just wanted to add two quick things (one mostly aspirational, the other useful)

## Aspirational: Markdown/Ruby/deck.js

I am currently using this combination to put together a presentation based on a recent working paper. Maybe out of procrastination I decided to see if there was any way to use knitr/Markdown to write a deck.js presentation. I generally prefer deck.js to the three Pandoc HTML presentation types (slidy, S5, and dzslides).

Deck.js presentations are a pain to write, so it would be great if there was a program like Pandoc that could quickly convert a Markdown file into a deck.js presentation.

I discovered that there kind of is. There is a ruby program called deck.rb. The Markdown syntax is really simple and would be familiar to Pandoc users (individual slides are demarcated with the first level header #).

After you install deck.rb in the terminal with the usual:

    sudo gem install deckrb


you can easily build presentations in the command line with:

    deck myPresentation.md


However, I’ve classified this as aspirational since it lacks a lot of functionality that Pandoc has, including:

• There really aren’t title slides.

• The slideshow opens as a locally hosted webserver, and the command to build a stand alone HTML presentation doesn’t seem to work that well (hence no example included with this post).

• It only allows you to use the Swiss template.

• I couldn’t figure out how to easily get MathJax support to display equations.

Maybe I won’t use use deck.rb for this presentation, but I will keep an eye on any developments.

## Useful Tip: Command Line/Go2Shell

Since I’m on about the terminal and command line, I thought I might mention a small (free) program that is very helpful: Go2Shell. It is a little Mac application that only opens a new terminal window from the folder that you currently have open.

Very useful for easily setting your terminal working directory when, for example, making Pandoc presentations.

Yihui Xie said…
I'm also looking for a good markdown-to-deck.js conversion tool. If you find one some day, please let me know or write a blog post on it. Thanks!
I'll definitely post anything that I find.

And thanks for putting together knitr!
Ramnath said…
Check out slidify - An R package designed to make it easy to generate reproducible HTML5 slides, using knitr and R markdown. (https://github.com/ramnathv/slidify)
Alex Chaffee said…
I wrote deck.rb and I agree with all your feature requests -- I don't have a lot of time to work on the tool right now, but I'm open to patches or even persistent nagging :-)

Any idea on how to implement the last one? I'm using RedCarpet with markdown extensions; maybe there's one for equations, or maybe we can roll our own.
Alex Chaffee said…
"There aren't really title slides" -- If a slide contains only a single H1 then it gets really big... I agree that's not quite a title slide, but can you tell me more how you think a real title slide would work?

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