[Dev] Model

[ocots]

• Make constraints at build
• Handle labels to get dual variables

[PierreMartinon]

Hi @ocots,

Tests with the new model:

• scalar / vector case seems to work fine
• no more runtime dispatch or allocations from mayer, lagrange and dynamics
• still some dispatch/allocs for the constraints, I tried to use parametrization but did not manage to get rid of the problem. Maybe building them inside the Model would solve this too ?

Some comparisons vs main branch (NB. these small problems have no path constraints)

problem	main	new model
simple integrator (energy)	42ms / 44MB	33ms / 29MB
fuller	52ms / 47MB	42ms / 30MB
double integrator (tf)	48ms / 41MB	38ms / 31MB

Definitely some progress. I'll start working on the block structure for the jacobian too.

Remarks:

• yes, building the constraints functions inside the model will be more convenient.
• objective functions (lagrange and mayer) always return scalar values, and out of place would be more convenient here than inplace. Done :D
• variable_constraints is actually redundant with boundary_constraints and variable box constraints, it can be removed from the model !
• If a user tries to declare explicitely

CTModels.variable!(pre_ocp, 0)

for a variable independent problem, the variable dimension is actually set to 1.
There should probably also be a message saying that the declaration is not needed.

• I keep getting runtime dispatch warnings when using the getters for initial and final time, even when qualifying the TimesModel. Reverted back to using duplicate variables in DOCP for the fixed / free times for now. Maybe we can discuss this point together ?

[ocots]

This seems to be a good news!

I modify for the dimension 0. For a state and a control, it is forbidden and for a variable it is possible but I will set with an empty variable.

[ocots]

Ok we need to discuss about the times.

[ocots]

For the out-of-place, actually, I have nothing to change :-) It will be at parsing to adapt. Actually, you can already test with out of place for the objective functions.

[ocots]

Up to now:

• dimension 0 for state, control and variable
• out of place (up to you)
• constraints built during model building so it is done once and we have the types.

[ocots]

I have added a function to get the times, with a variable even if the time is fixed.