export function distanceBetween()

in packages/geofire-common/src/index.ts [370:385]

• 12 lines of code
• 1 McCabe index (conditional complexity)

export function distanceBetween(location1: Geopoint, location2: Geopoint): number {
  validateLocation(location1);
  validateLocation(location2);

  const radius = 6371; // Earth's radius in kilometers
  const latDelta = degreesToRadians(location2[0] - location1[0]);
  const lonDelta = degreesToRadians(location2[1] - location1[1]);

  const a = (Math.sin(latDelta / 2) * Math.sin(latDelta / 2)) +
    (Math.cos(degreesToRadians(location1[0])) * Math.cos(degreesToRadians(location2[0])) *
      Math.sin(lonDelta / 2) * Math.sin(lonDelta / 2));

  const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));

  return radius * c;
}