Calculate distance between two GPS latitude and longitude coordinates PHP

Not much to say, just code it yourself, you can use it directly.

/**
 * 计算两个坐标之间的距离(米)
 * @param float $fP1Lat 起点(纬度)
 * @param float $fP1Lon 起点(经度)
 * @param float $fP2Lat 终点(纬度)
 * @param float $fP2Lon 终点(经度)
 * @return int
 */
function distanceBetween($fP1Lat, $fP1Lon, $fP2Lat, $fP2Lon){
	$fEARTH_RADIUS = 6378137;
	//角度换算成弧度
	$fRadLon1 = deg2rad($fP1Lon);
	$fRadLon2 = deg2rad($fP2Lon);
	$fRadLat1 = deg2rad($fP1Lat);
	$fRadLat2 = deg2rad($fP2Lat);
	//计算经纬度的差值
	$fD1 = abs($fRadLat1 - $fRadLat2);
	$fD2 = abs($fRadLon1 - $fRadLon2);
	//距离计算
	$fP = pow(sin($fD1/2), 2) +
		  cos($fRadLat1) * cos($fRadLat2) * pow(sin($fD2/2), 2);
	return intval($fEARTH_RADIUS * 2 * asin(sqrt($fP)) + 0.5);
}
/**
 * 百度坐标系转换成标准GPS坐系
 * @param float $lnglat 坐标(如:106.426, 29.553404)
 * @return string 转换后的标准GPS值:
 */
function BD09LLtoWGS84($fLng, $fLat){ // 经度,纬度
	$lnglat = explode(',', $lnglat);
	list($x,$y) = $lnglat;
	$Baidu_Server = "http://api.map.baidu.com/ag/coord/convert?from=0&to=4&x={$x}&y={$y}";
	$result = @file_get_contents($Baidu_Server);
	$json = json_decode($result);
	if($json->error == 0){
		$bx = base64_decode($json->x);
		$by = base64_decode($json->y);
		$GPS_x = 2 * $x - $bx;
		$GPS_y = 2 * $y - $by;
		return $GPS_x.','.$GPS_y;//经度,纬度
	}else
		return $lnglat;
}

The above introduces the calculation of the distance between two GPS longitude and latitude coordinates in PHP, including aspects of the content. I hope it will be helpful to friends who are interested in PHP tutorials.