Improving cost function plotting?

[davidhowey]

Feature description

The cost landscape plots are super cool! I think it would be nice to make some minor changes to how they work to improve understandability. It would help users to interpret these plots if it was easier to see certain aspects. For example, it's not very obvious at the moment where the initial guess and the final (optimised) points actually are. Could we make these clearer, e.g., by circling them or similar, and/or adding some annotation text?

Motivation

No response

Possible implementation

No response

Additional context

No response

[BradyPlanden]

Agreed, #198 changes the initial position from the red 'X' to a green circle, once #177 is merged we can update this with clearer annotations.

At the same time as the above, the method should be updated for vectorised inputs in the model.simulate() call. As the casadi solver can accept vectorised input in the form of a dict, this should speed up the plotting time considerably.

Reference: https://docs.pybamm.org/en/latest/source/api/solvers/base_solver.html#pybamm.BaseSolver.solve

[BradyPlanden]

Things to consider adding:

• Scale for optimiser marker colouring (or more commentary in examples)
• Fix the axis titles when plotting \micro as .svg within the notebooks. See: https://github.com/pybop-team/PyBOP/blob/develop/examples/notebooks/spm_electrode_design.ipynb