geostat/cache.cpp

#include "cache.h"

#include <cmath>
const static int Earth_radius = 6378;

Position Cache::home;

static float degtorad(float x) {
	return x * M_PI / 180;
}
void Cache::show() const {
	std::cout << "Cache:\t" << code << ' ' << name << '\n';
	std::cout << '\t' << pos.lat << " " << pos.lon << "\t\t D/T: " << diff << '/' << terr << '\n';
}

float Cache::distance() const {
	return 2 * Earth_radius * asin(sqrt(pow(sin(degtorad((pos.lat - home.lat) / 2)), 2) + cos(degtorad(pos.lat)) * cos(degtorad(home.lat)) * pow(sin(degtorad((pos.lon - home.lon) / 2)), 2)));
};

bool CacheCmpNS(const Cache& lhs, const Cache& rhs) {
	return lhs.pos.lat < rhs.pos.lat;
}

bool CacheCmpEW(const Cache& lhs, const Cache& rhs) {
	return lhs.pos.lon < rhs.pos.lon;
}

bool CacheCmpDist(const Cache& lhs, const Cache& rhs) {
	return lhs.distance() < rhs.distance();
}