This is a wrap-up post to summarize a few of the issues I’ve found so far with blogging on tumblr with R Markdown.
tumblr Puts a 1Mb Cap On Its HTML Editor
Fair warning.
When I tried eating my own dogfood while writing the previous posts, I found that I had to manually upload all those pretty screenshots of the tumblr interface. For some reason, tumblr was truncating the HTML I was pasting into its editor. By trial and error, I found out that they place a cap of around 1Mb on the HTML. That’s essentially 96 R plots at 504x432 pixels. How do I know? Because I placed this bit of code:
for (i in 1:96)
plot(rnorm(i), main = paste(i, "Squares"),
col = rainbow(i, alpha = runif(i, 0, 1))[round(runif(i, 1, i))],
pch = ".", cex = round(runif(i, 1, 100)))
into an R Markdown file, rendered it to HTML with markdownToHTML(), and uploaded it to my test blog http://testerester.tumblr.com a number of times. Maxed out at 96. Regardless, that’s 96 images I didn’t have to upload manually!
R Highlighting Is Now Fixed
I presumed that the hosted version of highlight.js contained a language definition for R. It actually does not, but it’s easy to include one. I’ve done such and am now hosting my own highlight.packed.js on rapache.net here:
http://rapache.net/stylesheets/highlight.pack.js
and have updated the tumblr R Markdown theme here:
https://github.com/jeffreyhorner/RFMExamples/blob/master/R-Markdown-tumblr-theme.html
You Can Drop the Save in the Edit/Save/Knit Iteration
JJ Allaire assures me that you don’t have to save your R Markdown document before you knit it in RStudio. It is saved automatically, and dropping the save action speeds up iterative development by a factor 1.5!
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Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).