A while ago I was asked to give a presentation at my job about using R to create statistical graphics. I had also just read some reviews of the Slidify package in R and I thought it would be extremely appropriate to create my presentation about visualization in R, in R. So I set about breaking in the Slidify package and I’ve got to give a huge shout out to Ramnath Vaidyanathan who created this package. It was a pleasure to use and at one point I had a question and I posted on his GitHub and he responded helpfully and promptly. What a great guy! Here’s a link to the final product posted on RPubs:
Check it out, it’s full of gorgeous figures and formatting. It’s really an accomplishment to get something this nice looking out of a command line program. Most of the credit for the formatting beauty goes to the Slidify package. I uses markdown in much the same way as knitr does, so if you’re familiar with that, using Slidify isn’t a big jump.
Some comments on the whole experience:
- While Slidify does a nice job with formatting (notice in particular headings, regular text, bullets, and set off code chunks with the different background color), especially for markdown, it’s not perfect. For example I had trouble gauging the appropriate amount of material for each slide. If you try to cram too much on one slide, instead of compressing to fit all of it (as PowerPoint would), your text/figure/whatever just hangs off of the bottom of the slide out of sight. It was frustrating to have to guess and check the amount of material in each slide, especially with figures and material I decided to go back and add.
- I loved the fact that I could add images from my hard drive, not just images generated in R. You’ll notice in my slideshow that I made use of this when I took screen shots of reshapeGUI in action and included them. This was really easy to do and a great feature. I would say the same for hyperlinks. These were easy to add and extremely useful since I ended up publishing the presentation to the web. Those watching didn’t have to jot down a link or a book title every time I suggested a good place to find extra info about something. I just emailed around a link to the presentation and everyone had all of the resources just a click away.
- This brings me to the most frustrating part of the whole thing: Publishing online. Now this is not an issue with Slidify, but rather with Rpubs and GitHub. I’d never published anything from R directly to either, and setting this functionality up proved extremely painful. I first tried to push the thing to GitHub because I already had a GitHub account, but I never managed to figure it out. After much frustration I tried Rpubs. By pure determination I finally stumbled my way through the setup process for that and eventually published the presentation to my new Rpubs account. I honestly don’t even remember what all I had to do, but I remember this being incredibly frustrating. The documentation accompanying Slidify could be improved by adding a how-to section for those who have never uploaded to either online repository. UPDATE: The author of the package pointed out to me that you can also publish your slideshow using Dropbox. This is done simply by saving the slideshow into your Dropbox folder. I wish I’d known this, because you can’t get mush easier than that!
In summation, I was really impressed with Slidify, but in the end, there was no reason to use this instead of a traditional PowerPoint (other than to show off that I had made my presentation about R, in R). PowerPoint (or Google Docs or some other free presentation software) would allow me the same functionality and more without having to struggle from behind a command line. The only reason I can see to do a presentation this way is if you might need to update it frequently (such as update regularly with recent data, etc), much the same type of things you might use a markdown document for. The problem with this is as your data changes, your output and figures will change, but your text discussing it will not, which is dangerous. The same goes for markdown documents as well though, and those get used quite frequently. So overall, I highly recommend Slidify, but you need to have the right reasons to do so. Happy presenting!