How to set different global options in knitr and RStudio for word and html?

Question

I am using RStudio 0.98.932 and knitr 1.6. Would like to set different global knitr options for word and html. For example, want to set fig.width and fig.height as 6 for word an

Answer 1

Try putting this code chunk at the beginning of the Rmd document.

```{r setup, cache=FALSE, include=FALSE}
library(knitr)
output <- opts_knit$get("rmarkdown.pandoc.to")
if (output=="html") opts_chunk$set(fig.width=11, fig.height=11)
if (output=="docx") opts_chunk$set(fig.width=6,  fig.height=6)
```

One of the package options returned by opts_knit$get() is markdown.pandoc.to. This is evidently set to "html", "docx", or "latex" depending on the chosen output format (HTML, Word, or PDF). So you can test that and set the chunk options fig.width and fig.height accordingly.