Example with different volumes

[rogerkuou]

We can add examples with different volumes.
E.g. we can show examples of computing eigenvectors to check if a point belongs to a certain surface, as it was mentioned in the paper: https://www.sciencedirect.com/science/article/pii/S2352711020303393

[meiertgrootes]

Good idea. We can lift the code for that from the paper code. I'll check where it could be