How to export multiple graphs/plots per code block in org-mode?

Question

If my R code, which plots several graphs, is contained within one babel code block in org-mode, is it possible to export all of the graphs and display them in the #+RESULT section after evaluating the code?

• Using Spacemacs 200.9@25.1.1, Org-mode v.9.0.5, ESS and R 3.3.3

Answer 1

You could look into scimax's ob-ipython extensions, as described here.

Quoting the author:

I wrote one new function that writes the base64 data out to a temporary file and returns a link to it. Then, I modified the org-babel-execute:ipython function to append these links onto the output.

The code is written for SRC blocks targetying ipython, but you can probably modify it so that it works for R in the same way. None of the ideas in the implementation seem to be specific to Python.

The scimax ob-ipynb exporter already offers support for R.

Answer 2

I don't know how to export multiple graphs per one #+RESULTS.

But I might export multiple graphs, or handle multiple inline images within org-mode, by a dirty way.

Just save graph files by png(), pdf(), etc.

#+BEGIN_SRC R :session *R* :results output :exports none
d<-1:5
dd<-data.frame(cbind(x=d, y=d^2, z=d^3))
for(i in 1:3){
    png(paste0("tmp",i,".png"))
    plot(dd[,i],type="b",pch=16,col=i,cex=i,main=paste0("tmp",i))
    dev.off()}
#+END_SRC

Then, just make links for each graphic files by hands ;)

If you change the data, such as d<-1:10, and execute the source code block by C-c C-c, you can see multiple inline images reflect the results simultaneously.

Making links with numbering are stupid simple tasks, I'm sure Emacs Lisp handle numbering tasks without difficulty!

#+CAPTION: tmp1
#+NAME: tmp1
#+ATTR_LaTeX: :height 4cm
#+ATTR_HTML: :width 360
[[file:tmp1.png]]

#+CAPTION: tmp2
#+NAME: tmp2
#+ATTR_LaTeX: :height 4cm
#+ATTR_HTML: :width 360
[[file:tmp2.png]]

#+CAPTION: tmp3
#+NAME: tmp3
#+ATTR_LaTeX: :height 4cm
#+ATTR_HTML: :width 360
[[file:tmp3.png]]