如何使用PHP测量距离？

Question

我应该首先说，在PHP方面我还是很绿，所以请耐心等待我。我试图用php计算两个纬度和经度之间的距离。我在网上发现了一堆脚本，但是当我尝试测试它们时，无论我使用什么纬度和经度，我都会得到相同的距离。我相信这可能是我的意思，所以我只会发布我到目前为止的内容。

$lat1 = "29.140762";
$lon1 = "-91.639243";

$lat2 = "29.136275";
$lon2 = "-91.635524";

function distance($lat1, $lon1, $lat2, $lon2, $unit) {
    $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);
    $miles = $dist * 60 * 1.1515;
    $unit = strtoupper($unit);

    if ($unit == "K") {
        return ($miles * 1.609344);
    } else if ($unit == "N") {
        return ($miles * 0.8684);
    } else {
        return $miles;
    }
}

// Miles
echo distance(32.9697, -96.80322, 29.46786, -98.53506, "m") . " miles<br><br>";

//Kilometers
echo distance(32.9697, -96.80322, 29.46786, -98.53506, "k") . " kilometers<br><br>";

//Nautical miles
echo distance(32.9697, -96.80322, 29.46786, -98.53506, "n") . " nautical miles";

Answer 1

我猜你已经对输入进行了硬编码，只是更改页面顶部的变量并期待新的结果。那些变量目前没有做任何事情。尝试下面对函数调用所做的更改，现在可以识别变量。

// Miles
echo distance($lat1, $lon1, $lat2, $lon2, "m") . " miles<br><br>";

//Kilometers
echo distance($lat1, $lon1, $lat2, $lon2, "k") . " kilometers<br><br>";

//Nautical miles
echo distance($lat1, $lon1, $lat2, $lon2, "n") . " nautical miles";

Answer 2

不，它没有

刚试过它并输出

262.67779380543 miles

422.73893139401 kilometers

228.10939614064 nautical miles

更新

Here is another output when using 
// Miles
echo distance(35.9697, -96.80322, 29.46786, -98.53506, "m") . " miles<br><br>";

//Kilometers
echo distance(35.9697, -96.80322, 29.46786, -98.53506, "k") . " kilometers<br><br>";

//Nautical miles
echo distance(35.9697, -96.80322, 29.46786, -98.53506, "n") . " nautical miles";

  

460.32704312505英里

     

740.82456489105公里

     

399.7480042498海里