./ontology_viz.py -o test.dot test.ttl -O ontology.ttl
dot -Tpng -o test.png test.dot

• Use -o to indicate the path of output file
• Use -O to indicate the input ontology (Optional).
• Use -C to indicate the configuration file (Optional).
  • max_label_length: config the max length of labels. If the text exceeds the length, exceeded part will be replaced with “…”. Default value is 0.
  • blacklist: config the predicate that you don’t want to see in the graph.
  • class_inference_in_object: config the predicate that can inference the object is a Class, even if the class doesn’t defined in the ontology.
  • label_property: config the predicate that used for labeling nodes, if such a label exists, it will display inside the node.
  • tooltip_property: config the predicate that contains the tooltip texts.
  • bnode_regex: a list of regexes, if an uri matches, then it will be dispaly as a blank node without its uri nor label. It can be useful if you have a lot of reifications.
  • colors: config the colors of nodes
    • class, literal, instance can accept HEX value(e.g. "#ff0000" ), MATLAB style(e.g. "r" ), and color name (e.g. "red" ).

    "colors": {
      "class": "#ff0000",
      "literal": "r",
      "instance": "red",
    }
            

    • instance can also accept a dict value to specify the color of each class instance. And use "default" to to set color for undefined instances.

    "instance": {
      "https://tac.nist.gov/tracks/SM-KBP/2018/ontologies/SeedlingOntology#Facility": "#a6cee3",
      "default": "#ffff99"
    }
            

    • filled: config whether fill the node, default value: true.
• Classes defined in the ontology will be omitted in the output graph. This action can be switched with argument -V.

• -K to specify which layout algorithm to use. E.g. -Kneato and -Ksfdp . Notice that inorder to use sfdp layout algorithm, you will need to build your graphviz with GTS.
• -T to specify the output format.
• -G to set a graph attribute. E.g. -Goverlap=prism

In order to use this tool, you’ll need to make sure you have rdflib installed.

In order to convert dot into png or svg image, you will need Graphviz.