double_sampler.hpp

/*
 * Copyright (c) 2019 - 2025 Geode-solutions
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 *
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#pragma once

#include <geode/stochastic/sampling/distributions.hpp>

#include <variant>

namespace geode
{
    class RandomEngine;
} // namespace geode

namespace geode
{

    struct opengeode_stochastic_stochastic_api DoubleSampler
    {
        using Distribution = std::variant< UniformClosed< double >,
            UniformClosedOpen< double >,
            Gaussian,
            TruncatedGaussian,
            VonMises >;

        struct DistributionDescription
        {
            std::string name{ "default_distribution" };
            DistributionType distribution_type;

            std::optional< double > min_value;
            std::optional< double > max_value;
            std::optional< double > mean;
            std::optional< double > standard_deviation;

            std::string string() const
            {
                auto message = absl::StrCat( "Distribution - ", name );
                absl::StrAppend( &message,
                    "\n\t - distribution type: ", distribution_type.get() );
                if( min_value.has_value() )
                {
                    absl::StrAppend(
                        &message, "\n\t - min value: ", min_value.value() );
                }
                if( max_value.has_value() )
                {
                    absl::StrAppend(
                        &message, "\n\t - max value: ", max_value.value() );
                }
                if( mean.has_value() )
                {
                    absl::StrAppend(
                        &message, "\n\t - mean value: ", mean.value() );
                }
                if( standard_deviation.has_value() )
                {
                    absl::StrAppend( &message,
                        "\n\t - std value: ", standard_deviation.value() );
                }
                return message;
            }
        };

        static Distribution create_distribution(
            const DistributionDescription& desc );
        static Distribution create_rad_angle_distribution_from_degree(
            const DistributionDescription& angle_desc_deg );

        static double sample( RandomEngine& engine, const Distribution& dist );
    };

} // namespace geode