Source code for qiskit_algorithms.optimizers.nlopts.crs

# This code is part of a Qiskit project.
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# (C) Copyright IBM 2018, 2023.
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# This code is licensed under the Apache License, Version 2.0. You may
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"""Controlled Random Search (CRS) with local mutation optimizer."""

from .nloptimizer import NLoptOptimizer, NLoptOptimizerType


class CRS(NLoptOptimizer):
    """
    Controlled Random Search (CRS) with local mutation optimizer.

    Controlled Random Search (CRS) with local mutation is part of the family of the CRS optimizers.
    The CRS optimizers start with a random population of points, and randomly evolve these points
    by heuristic rules. In the case of CRS with local mutation, the evolution is a randomized
    version of the :class:`NELDER_MEAD` local optimizer.


    NLopt global optimizer, derivative-free.
    For further detail, please refer to
    https://nlopt.readthedocs.io/en/latest/NLopt_Algorithms/#controlled-random-search-crs-with-local-mutation
    """

    def get_nlopt_optimizer(self) -> NLoptOptimizerType:
        """Return NLopt optimizer type"""
        return NLoptOptimizerType.GN_CRS2_LM