include/Utilities/geographic.h

#ifndef GEOGRAPHIC_H
#define GEOGRAPHIC_H

#include <math.h>

#define pi 3.14159265358979323846

/*:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::*/
/*::  This function converts decimal degrees to radians             :*/
/*:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::*/
double deg2rad(double deg) {
  return (deg * pi / 180);
}

/*:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::*/
/*::  This function converts radians to decimal degrees             :*/
/*:::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::*/
double rad2deg(double rad) {
  return (rad * 180 / pi);
}

double haversineDistanceInMeters(double lat1, double lon1, double lat2, double lon2) {
  double theta, dist;
  theta = lon1 - lon2;
  dist = sin(deg2rad(lat1)) * sin(deg2rad(lat2)) + cos(deg2rad(lat1)) * cos(deg2rad(lat2)) * cos(deg2rad(theta));
  dist = acos(dist);
  dist = rad2deg(dist);
  dist = dist * 60 * 1.1515;
  dist = dist * 1609.344;
  return (dist);
}

double euclideanDistance( double x1, double y1, double x2, double y2)
{
    return ceil(sqrt(pow(abs( x1 - x2),2) + pow(abs( y1 - y2),2)));
}

#endif //GEOGRAPHIC_H

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