Source code for qiskit_algorithms.optimizers.nlopts.sbplx

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"""Sbplx (Subplex) optimizer."""

from .nloptimizer import NLoptOptimizer, NLoptOptimizerType




class SBPLX(NLoptOptimizer):
    """
    Subplex optimizer.

    "Subplex (a variant of Nelder-Mead that uses Nelder-Mead on a sequence of subspaces)
    is claimed to be much more efficient and robust than the original Nelder-Mead,
    while retaining the latter's facility with discontinuous objectives,
    and in my experience these claims seem to be true in many cases.
    (However, I'm not aware of any proof that Subplex is globally convergent,
    and perhaps it may fail for some objectives like Nelder-Mead; YMMV.)"
    Description by Steven G. Johnson, author of NLopt library.

    NLopt local optimizer, derivative-free.
    For further detail, please refer to
    https://nlopt.readthedocs.io/en/latest/NLopt_Algorithms/#sbplx-based-on-subplex
    """



    def get_nlopt_optimizer(self) -> NLoptOptimizerType:
        """Return NLopt optimizer type."""
        return NLoptOptimizerType.LN_SBPLX