Source code for qiskit_machine_learning.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.
    While these claims seem to be true in many cases, we could not find any proof that
    Subplex is globally convergent, and perhaps it may fail for some objective functions
    like Nelder-Mead; YMMV.)', 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