DiagrammeR – How to use PDF Diagrams Instead of PNG

[Amarakon]

I can create this nice diagram using DiagrammeR:

DiagrammeR::grViz("digraph {
  graph [layout = dot, rankdir = TB]
  
  node [shape = rectangle]        
  rec1 [label = 'Step 1. Wake up']
  rec2 [label = 'Step 2. Write code']
  rec3 [label =  'Step 3. ???']
  rec4 [label = 'Step 4. PROFIT']
  
  # edge definitions with the node IDs
  rec1 -> rec2 -> rec3 -> rec4
  }",
  height = 200)

But I noticed that the diagram's resolution is really bad. This is because it exports to a PNG image insteaad of a PDF. Most diagrams I do export to PDF so their quality is really good, but DiagrammeR exports to PNG for some reason. How can I make it export to PDF?

[JOhoney]

Hi, have you found a solution for this?

[Amarakon]

No, unfortunately not. If I do find a solution, I will update this post.

[michaelbgarcia]

I found a solution on SO that may fit your needs. Does this work?

library(DiagrammeR)
library(DiagrammeRsvg)
library(rsvg)
DiagrammeR::grViz("digraph {
  graph [layout = dot, rankdir = TB]
  
  node [shape = rectangle]        
  rec1 [label = 'Step 1. Wake up']
  rec2 [label = 'Step 2. Write code']
  rec3 [label =  'Step 3. ???']
  rec4 [label = 'Step 4. PROFIT']
  
  # edge definitions with the node IDs
  rec1 -> rec2 -> rec3 -> rec4
  }",
                  height = 200) %>% 
  DiagrammeRsvg::export_svg() %>% 
  charToRaw() %>% 
  rsvg::rsvg_pdf("svg_graph.pdf")

[Amarakon]

This worked, thanks. But there is one problem. It only exports the PDF file, it doesn't include it in my PDF output. So I have to do it manually right after the code block:


Is there a way to

1. Automate it exporting to PDF so I don't have to do it every time and choose the file name every time
2. Show it in my output