Make a clear distinction between states and non-states in the data structures

[SouthEndMusic]

Feature type

None

Improvement Description

It is really nice to be able to see at a glance what is being solved for.

Implementation Description

One possibility is the OrdinaryDiffEq (and SciML) standard form:

• du: The time derivatives of the states
• u: The states. Can be any vector-like object or a custom struct
• p: The parameters. Also contains preallocated memory for state-derived variables
• t: The current simulation time

But separating states and state derived variables in the data structures (and possibly collecting all states into one structure) would already help.

Additional Context

No response