Investigate networkx compatibility with graphviz Python library over pygraphviz

[matthewfeickert]

While trying to get graphviz (the C library) installed in a useful manner on lxplus8 (c.f. recast-hep/recast-atlas#82) I've found that trying to get a custom built and installed (e.g. from source) graphviz library to work with an install of pygraphviz from PyPI is quite difficult to get right.

---

Note: pygraphviz is required in yadage[viz]

        "viz": [
            # manually adding extras of adage[extra] because of pip
            # issue https://github.com/pypa/pip/issues/3189
            "pydot2",
            "pygraphviz",
            "pydotplus",
        ],

because adage[viz] requires it

adage/setup.py

Line 5 in 9ae49b3

"viz": ["pydot", "pygraphviz", "pydotplus"],

---

However, what is surprisingly easy to get working is the Python library graphviz, which has wheels, appears to be very developed, and is basically good to go as long as

the directory containing the dot executable is on your systems' PATH

It is unclear if networkx and the Python graphviz can work together, but if they can this seems to be a much better way to go than pygraphviz.

[matthewfeickert]

Though seems like this is maybe not possible, given xflr6/graphviz#50.