mathop.h

// Mathematical Operations
// Written by Sergey G. Kosov in 2017 for Project X
#pragma once

#include "types.h"
#include "macroses.h"

namespace DirectGraphicalModels
{
    // ================================ Random Namespace ==============================
    namespace mathop {
        template <typename T>
        inline bool isEqual(const Mat &a, const Mat &b)
        {
            // Assertions
            DGM_ASSERT_MSG(a.size() == b.size(), "Size mismatch");
            DGM_ASSERT_MSG(a.type() == b.type(), "Type mismatch");

            if (a.cols == 1) {
                for (int j = 0; j < a.rows; j++)
                    if (a.at<T>(j, 0) != b.at<T>(j, 0)) return false;
            }
            else if (a.rows == 1) {
                for (int i = 0; i < a.cols; i++) {
                    if (a.at<T>(0, i) != b.at<T>(0, i)) return false;
                }
            }
            else {
                for (int j = 0; j < a.rows; j++) {
                    const T *pa = a.ptr<T>(j);
                    const T *pb = b.ptr<T>(j);
                    for (int i = 0; i < a.cols; i++)
                        if(pa[i] != pb[i]) return false;
                }
            }
            return true;
        }
        template <typename Targ = float, typename Tres = float>
        inline Tres Euclidian(const Mat &a, const Mat &b)
        {
            // Assertions
            DGM_ASSERT_MSG(a.size() == b.size(), "Size mismatch");
            DGM_ASSERT_MSG(a.type() == b.type(), "Type mismatch");

            Tres res = 0;
            if (a.cols == 1) {
                for (int j = 0; j < a.rows; j++)
                    res += (static_cast<Tres>(a.at<Targ>(j, 0)) - static_cast<Tres>(b.at<Targ>(j, 0))) * (static_cast<Tres>(a.at<Targ>(j, 0)) - static_cast<Tres>(b.at<Targ>(j, 0)));
            }
            else if (a.rows == 1) {
                for (int i = 0; i < a.cols; i++) {
                    res += (static_cast<Tres>(a.at<Targ>(0, i)) - static_cast<Tres>(b.at<Targ>(0, i))) * (static_cast<Tres>(a.at<Targ>(0, i)) - static_cast<Tres>(b.at<Targ>(0, i)));
                }
            }
            else {
                for (int j = 0; j < a.rows; j++) {
                    const Targ *pa = a.ptr<Targ>(j);
                    const Targ *pb = b.ptr<Targ>(j);
                    for (int i = 0; i < a.cols; i++)
                        res += (static_cast<Tres>(pa[i]) - static_cast<Tres>(pb[i])) * (static_cast<Tres>(pa[i]) - static_cast<Tres>(pb[i]));
                }
            }
            res = sqrt(res);
            return res;
        }

        template <typename T>
        inline T Euclidian(const std::vector<T> &a, const std::vector<T> &b)
        {
            T sum = 0;
            for (size_t i = 0; i < a.size(); i++)
                sum += (a[i] - b[i]) * (a[i] - b[i]);
            return sqrt(sum);
        }

        template<typename T>
        bool ifOverlap(pair_mat_t &box1, pair_mat_t &box2)
        {
            for (int x = 0; x < box1.first.cols; x++) {
                if (box1.first.at<T>(0, x) > box2.second.at<T>(0, x))   return false;
                if (box1.second.at<T>(0, x) < box2.first.at<T>(0, x))   return false;
            }
            return true;
        }
    }
}