[RTR] integration rule tested in collocation

[Ipuch]

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This change is 

[pariterre]

GG so far

Reviewed 2 of 2 files at r1, all commit messages.
Reviewable status: all files reviewed, 4 unresolved discussions (waiting on @Ipuch)

---

bioptim/optimization/solution.py line 1302 at r1 (raw file):

                        or penalty.integration_rule == IntegralApproximation.TRAPEZOIDAL
                    ):
                        col_x_idx.append((idx + 1) * steps) if nlp.ode_solver.is_direct_shooting else col_x_idx.append(

I feel that it is not what you expect. See suggestion

Suggestion:

                        col_x_idx.append((idx + 1) * (steps if nlp.ode_solver.is_direct_shooting else 1))

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tests/test_cost_function_integration.py line 118 at r1 (raw file):

    Sum the cost function output from sol.print_cost()
    """
    capturedOutput = io.StringIO()  # Create StringIO object

Please change that to camel_casing

Code quote:

capturedOutput 

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tests/test_cost_function_integration.py line 217 at r1 (raw file):

    "objective",
    [
        # "torque",

Why is this commented?

Code quote:

 # "torque",

---

tests/test_cost_function_integration.py line 228 at r1 (raw file):

    "integration_rule",
    [
        # IntegralApproximation.RECTANGLE,

Why is this commented?

Code quote:

        # IntegralApproximation.RECTANGLE,
        IntegralApproximation.TRAPEZOIDAL,
        # IntegralApproximation.TRUE_TRAPEZOIDAL,

[pariterre]

Reviewed 2 of 2 files at r2, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @Ipuch)