WisdomCache.h

// This file is part of openPSTD.                                       //
//                                                                      //
// openPSTD is free software: you can redistribute it and/or modify     //
// it under the terms of the GNU General Public License as published by //
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//                                                                      //
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// but WITHOUT ANY WARRANTY; without even the implied warranty of       //
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the        //
// GNU General Public License for more details.                         //
//                                                                      //
// You should have received a copy of the GNU General Public License    //
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//
// Date: 29-9-15
//
//
// Authors: Omar Richardson, Louis van Harten
//
//
#ifndef OPENPSTD_WISDOMCACHE_H
#define OPENPSTD_WISDOMCACHE_H

#include <map>
#include <math.h>
#include <fftw3.h>
#include <complex>
#include <memory>
#include <iostream>
#include <Eigen/Dense>

namespace OpenPSTD {
    namespace Kernel {

        class WisdomCache {
        public:

            struct Discretization {
                Eigen::ArrayXf wave_numbers;
                Eigen::ArrayXcf complex_factors;
                Eigen::ArrayXcf pressure_deriv_factors;
                Eigen::ArrayXcf velocity_deriv_factors;
            };

            struct Planset_FFTW {
                fftwf_plan plan;
                fftwf_plan plan_inv;
            };

            Discretization get_discretization(float dx, int N); //Todo: should we include dx here?

            Planset_FFTW get_fftw_planset(int fft_length, int fft_batch_size);

            WisdomCache();

            std::map<int, Discretization> computed_discretization; // Should be private! public for debugging purposes
            std::map<std::string, Planset_FFTW> cached_fftw_plans; // Should be private! public for debugging purposes

        private:

            Discretization discretize_wave_numbers(float dx, int N); //Todo: Needs a better name

            Planset_FFTW create_fftw_planset(int fft_length, int fft_batch_size);

            int match_number(int n);
        };

        std::ostream &operator<<(std::ostream &str, WisdomCache const &v);
    }
}

#endif //OPENPSTD_WISDOMCACHE_H