elaboration of python3 -m semsql.subgraph dependency on ./node_modules/obographviz/bin/og2dot.js

[turbomam]

• Platform specific install of npm
  • Ubuntu 20? sudo apt install npm
• graphviz's dot needs to be on the path. There are several platform-dependent ways to accomplish that. sudo apt install graphviz
• Install obographviz locally. Documentation suggests -g globally, which might require changing permissions on a global folder.
  • npm install obographviz
• Add obographviz to path export PATH=$PATH:./node_modules/obographviz/bin/

Make sure installation of graphviz and obographviz are clear and differentiated.

python3 -m semsql.subgraph -d db/pato.db -f obojson -m label size > pato_size.json
og2dot.js --outfile pato_size.png --to=png  pato_size.json

note whitespace between subgraph and -d...