如何将给定的纬度和经度转换为以公里为单位的距离旅行

function calculateDistance(lat1, lon1, lat2, lon2) {
  const earthRadius = 6371; // 地球半径，单位为公里

  // 将经纬度转换为弧度
  const lat1Rad = toRadians(lat1);
  const lon1Rad = toRadians(lon1);
  const lat2Rad = toRadians(lat2);
  const lon2Rad = toRadians(lon2);

  // 计算经纬度的差值
  const latDiff = lat2Rad - lat1Rad;
  const lonDiff = lon2Rad - lon1Rad;

  // 应用Haversine公式计算距离
  const a = Math.sin(latDiff / 2) * Math.sin(latDiff / 2) +
            Math.cos(lat1Rad) * Math.cos(lat2Rad) *
            Math.sin(lonDiff / 2) * Math.sin(lonDiff / 2);
  const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
  const distance = earthRadius * c;

  return distance;
}

function toRadians(degrees) {
  return degrees * (Math.PI / 180);
}

// 示例使用
const lat1 = 40.7128; // 纬度1
const lon1 = -74.0060; // 经度1
const lat2 = 34.0522; // 纬度2
const lon2 = -118.2437; // 经度2

const distance = calculateDistance(lat1, lon1, lat2, lon2);
console.log(distance); // 输出两点之间的距离，单位为公里