binh_korn module¶
Binh and Korn multi-objective problem.
This module implements the Binh and Korn multi-objective problem as defined in [BK97]:
- class gemseo.problems.analytical.binh_korn.BinhKorn(initial_values=(1.0, 1.0))[source]
Bases:
OptimizationProblem
Binh and Korn optimization problem.
The constructor initializes the BinhKorn
OptimizationProblem
by defining theDesignSpace
, the objective function and the constraints.- Parameters:
initial_values (FigSizeType) –
Initial value of the design variables.
By default it is set to (1.0, 1.0).
- constraints: list[MDOFunction]
The constraints.
- current_iter: int
The current iteration.
- database: Database
The database to store the optimization problem data.
- design_space: DesignSpace
The design space on which the optimization problem is solved.
- eq_tolerance: float
The tolerance for the equality constraints.
- fd_step: float
The finite differences step.
- ineq_tolerance: float
The tolerance for the inequality constraints.
- max_iter: int
The maximum iteration.
- new_iter_observables: list[MDOFunction]
The observables to be called at each new iterate.
- nonproc_constraints: list[MDOFunction]
The non-processed constraints.
- nonproc_new_iter_observables: list[MDOFunction]
The non-processed observables to be called at each new iterate.
- nonproc_objective: MDOFunction
The non-processed objective function.
- nonproc_observables: list[MDOFunction]
The non-processed observables.
- observables: list[MDOFunction]
The observables.
- pb_type: ProblemType
The type of optimization problem.
- preprocess_options: dict
The options to pre-process the functions.
- solution: OptimizationResult | None
The solution of the optimization problem if solved; otherwise
None
.
- stop_if_nan: bool
Whether the optimization stops when a function returns
NaN
.
- use_standardized_objective: bool
Whether to use standardized objective for logging and post-processing.
The standardized objective corresponds to the original one expressed as a cost function to minimize. A
DriverLibrary
works with this standardized objective and theDatabase
stores its values. However, for convenience, it may be more relevant to log the expression and the values of the original objective.
Examples using BinhKorn¶
Multi-objective Binh-Korn example with the mNBI algorithm
Pareto front on Binh and Korn problem