Visualize call graphs for Python

Question

I am looking for a simple tool to visualize the call graph for Python modules (i.e. what function calls what function etc.).

It exists an abandoned package pycallgraph, which does not work anymore.

Is there any other package available to can represent Python call graphs?

Answer 1

I feel slightly guilty here for just capitalising on @MawgsaysreinstateMonica 's and @albert 's comments, which gives most of the answer, but I thought I'd just formalise it for another reader's benefit.

1. Install Doxygen.
2. Install Graphviz, and add its 'bin' directory
3. Run up Doxywizard, and select the "Call graphs" and "Called by graphs" options (these are unticked by default) [- ee @albert 's link https://stackoverflow.com/questions/52494608/how-to-use-doxygen-to-create-a-documentation-and-call-graphs-for-all-python-fi for the keyword equivalents.

This produces adequate call graphs, although they seem to get confused by Python's

if __main__:
   pass

clause. I just commented it out while producing the diagrams.

Answer 2

You can use pyan.py to generate a call graph. See this stackoverflow question for details.

Usage: pyan.py FILENAME... [--dot|--tgf]

Analyse one or more Python source files and generate an approximate call graph
of the modules, classes and functions within them.

Options:
  -h, --help           show this help message and exit
  --dot                output in GraphViz dot format
  --tgf                output in Trivial Graph Format
  -v, --verbose        verbose output
  -d, --defines        add edges for 'defines' relationships [default]
  -n, --no-defines     do not add edges for 'defines' relationships
  -u, --uses           add edges for 'uses' relationships [default]
  -N, --no-uses        do not add edges for 'uses' relationships
  -c, --colored        color nodes according to namespace [dot only]
  -g, --grouped        group nodes (create subgraphs) according to namespace
                       [dot only]
  -e, --nested-groups  create nested groups (subgraphs) for nested namespaces
                       (implies -g) [dot only]