Export AbstractKiteModels interface

[ufechner7]

Export:

• the abstract type AbstractKiteModels
• the type SysState (alrady done)
• the function init!
• the function next_step!
• the function update_sys_state
• document this interface

These functions shall be implemented in the packages KiteModels.jl and SymbolicKiteModels.jl . See also: OpenSourceAWE/KiteModels.jl#150

[1-Bart-1]

I want to add find_steady_state! here. I call this function separate from init!, and I have to continue doing this, as I don't always want to run init! with find_steady_state!

[ufechner7]

Can you explain what this function shall do, and what the parameters and the return values of this function shall be?

[1-Bart-1]

This function shall:

• Find a (semi)-steady state of the system, most importantly the tethers shall be in a steady state.
• If using the integrator to do this, the function doesn't need to return anything, and the updated integrator state should be steady.
• If this function is run before creating the integrator, it should return some kind of state (a vector or a sys_struct), representing the steady state.

function find_steady_state!(akm::AbstractKiteModel; kwargs) -> nothing
function find_steady_state!(akm::AbstractKiteModel; kwargs) -> state_object

[ufechner7]

I don't always want to run init! with find_steady_state!

This could be solved with a parameter of the init! function.

[ufechner7]

function find_steady_state!(akm::AbstractKiteModel; kwargs) -> nothing
function find_steady_state!(akm::AbstractKiteModel; kwargs) -> state_object

Then this function would not be type stable. Normally, a function that modifies the first parameter is just returning nothing.

[1-Bart-1]

What do you mean, we use Julia, so there will be different type-stable dispatches. The interface definition doesn't have to be type-stable.

[1-Bart-1]

This could be solved with a parameter of the init! function.

No, I want to run find_steady_state! without running init!

[1-Bart-1]

a function that modifies the first parameter is just returning nothing

Ok for me if it returns nothing, so then we only have:

function find_steady_state!(akm::AbstractKiteModel; kwargs) -> nothing

And if you want to provide the integrator (which I have as a field in the akm):
function find_steady_state!(akm::AbstractKiteModel, integrator::ODEIntegrator; kwargs) -> nothing

[ufechner7]

I suggest not to add find_steady_state! to the common interface for now. It is too much work to make it work with returning nothing, and no advantage of adding this to KiteUtils.