Dot cannot be run in Pycharm with Sphinx and Graphviz - path

Question

I am trying to create a class diagram with sphinx. For this I created a virtual environment in Pycharm and added this to conf.py:
extensions = ['sphinx.ext.autodoc','sphinx.ext.inheritance_diagram']
In my spamfilter.rst file I added the following lines:
Diagrams
=================
.. inheritance-diagram:: spamfilter
The output is not a diagram and looks like this.
The following warning is displayed:
WARNING: dot command 'dot' cannot be run (needed for graphviz output), check the graphviz_dot setting
When I look into the folder C:\Users\Name\PycharmProjects\documentation\venv\Lib\site-packages\graphviz, there is a dot.py file, so I do not understand what is wrong. A similar question for Mac OS has been asked here. I tried the solution but it seems like it only works for Mac, because when I paste export PATH=$PATH:~/opt/bin to the Pycharm Terminal, it tells me that the command export could not be found. Honestly I have problems understanding why sometimes you can just use packages and other times they cannot be found even when they are installed, I am self-taught and a beginner.

Answer 1

The "pip install graphviz" command installs a Python package that provides an interface to Graphviz (https://pypi.org/project/graphviz). This package is not required by Sphinx.
In order to create inheritance diagrams with Sphinx, the actual Graphviz toolkit (including dot.exe) must be installed. See https://www.graphviz.org.
If dot.exe is not in the PATH, you can use the graphviz_dot configuration option.

Answer 2

I had the same problem where rendering a C4 model with PlantUML didn't work in the IDE (PyCharm 2022.2.1 Pro) on a newer M1 MacOS Monterey. I had it working on a Big Sur intel Mac prior to the upgrade with no extra effort, so the chip change caused me to go down a lot of paths with Rosetta and so on that were all unsuccessful.
The error was:
Dot Executable: /opt/local/bin/dot
File does not exist
Cannot find Graphviz.
Graphviz was installed correctly, and dot was on my path, but it wasn't in /opt/local/bin/dot. Since it was in /opt/homebrew/bin/dot, all I needed to do was link the actual file with the path it was searching for:
cd /opt
sudo ln -s homebrew local
et voilà, PyCharm is now correctly rendering the puml in the IDE.