bin_grid.hpp

/*##################################################################################################
# This file is a part of PyPartMC licensed under the GNU General Public License v3 (LICENSE file)  #
# Copyright (C) 2022 University of Illinois Urbana-Champaign                                       #
# Authors: https://github.com/open-atmos/PyPartMC/graphs/contributors                              #
##################################################################################################*/

#pragma once

#include "pmc_resource.hpp"
#include "pybind11/stl.h"

extern "C" void f_bin_grid_ctor(void *ptr) noexcept;

extern "C" void f_bin_grid_dtor(void *ptr) noexcept;

extern "C" void f_bin_grid_init(
    const void *ptr,
    const int *n_bin,
    const int *type,
    const double *min,
    const double *max
) noexcept;

extern "C" void f_bin_grid_size(
    const void *ptr,
    int *val
) noexcept;

extern "C" void f_bin_grid_edges(
    const void *ptr,
    void *arr_data,
    const int *arr_size
) noexcept;

extern "C" void f_bin_grid_centers(
    const void *ptr,
    void *arr_data,
    const int *arr_size
) noexcept;

extern "C" void f_bin_grid_histogram_1d(
    const void *x_bin_grid_ptr_c,
    const void *x_data,
    const void *weight_data,
    const int *arr_size,
    void *output_data,
    const int *grid_size
) noexcept;

extern "C" void f_bin_grid_histogram_2d(
    const void *x_bin_grid_ptr_c,
    const void *x_data,
    const void *y_bin_grid_ptr_c,
    const void *y_data,
    const void *weight_data,
    const int *arr_size,
    void *output_data,
    const int *x_grid_size,
    const int *y_grid_size
) noexcept;

struct BinGrid {
    PMCResource ptr;

    BinGrid(const int &n_bin, const std::string &grid_type, const double &min, const double &max) :
        ptr(f_bin_grid_ctor, f_bin_grid_dtor)
    {
        int type = 0;
        if (grid_type == "log") type = 1;
        if (grid_type == "linear") type = 2;
        if (type == 0)
            throw std::invalid_argument( "Invalid grid spacing." );

        f_bin_grid_init(ptr.f_arg(), &n_bin, &type, &min, &max);
    }

    static std::size_t __len__(const BinGrid &self) {
        int len;
        f_bin_grid_size(
            self.ptr.f_arg(),
            &len
        );
        return len;
    }

    static auto edges(const BinGrid &self)
    {
        int len;
        f_bin_grid_size(
            self.ptr.f_arg(),
            &len
        );
        len++;
        std::valarray<double> data(len);
        f_bin_grid_edges(
            self.ptr.f_arg(),
            begin(data),
            &len
        );
        return data;
    }

    static auto centers(const BinGrid &self) 
    {
        int len;
        f_bin_grid_size(
            self.ptr.f_arg(),
            &len
        );
        std::valarray<double> data(len);
        f_bin_grid_centers(
            self.ptr.f_arg(),
            begin(data),
            &len
        );
        return data;
    }
};

std::valarray<double> histogram_1d(
    const BinGrid &bin_grid,
    std::valarray<double> values,
    std::valarray<double> weights
);

std::vector<std::vector<double>> histogram_2d(
    const BinGrid &x_bin_grid,
    std::valarray<double> x_values,
    const BinGrid &y_bin_grid,
    std::valarray<double> y_values,
    std::valarray<double> weights
);