PHP中一系列位置之间的总距离

a = sin²(Δlat/2) + cos(lat1) * cos(lat2) * sin²(Δlon/2)
c = 2 * atan2(√a, √(1-a))
d = R * c

function calculateTotalDistance($locations) {
    $totalDistance = 0;
    
    for ($i = 0; $i < count($locations) - 1; $i++) {
        $lat1 = deg2rad($locations[$i]['lat']);
        $lon1 = deg2rad($locations[$i]['lon']);
        $lat2 = deg2rad($locations[$i+1]['lat']);
        $lon2 = deg2rad($locations[$i+1]['lon']);
        
        $deltaLat = $lat2 - $lat1;
        $deltaLon = $lon2 - $lon1;
        
        $a = sin($deltaLat/2) * sin($deltaLat/2) + cos($lat1) * cos($lat2) * sin($deltaLon/2) * sin($deltaLon/2);
        $c = 2 * atan2(sqrt($a), sqrt(1-$a));
        $distance = 6371 * $c; // 地球平均半径为6371公里
        
        $totalDistance += $distance;
    }
    
    return $totalDistance;
}

// 示例位置数据
$locations = [
    ['lat' => 40.7128, 'lon' => -74.0060], // 纽约
    ['lat' => 34.0522, 'lon' => -118.2437], // 洛杉矶
    ['lat' => 51.5074, 'lon' => -0.1278], // 伦敦
    ['lat' => 48.8566, 'lon' => 2.3522] // 巴黎
];

$totalDistance = calculateTotalDistance($locations);
echo "总距离：" . $totalDistance . "公里";