distance between two latitude and longitude using php

distance between two latitude and longitude using php

  /* PHP  */
  //Get latitude and longitude from geo data
    $latitudeFrom = '11.016844';
    $longitudeFrom = '76.955832';
    $latitudeTo = '11.232103';
    $longitudeTo = '77.106716';

	$unit = 'z';

 	$theta = $longitudeFrom - $longitudeTo;
    $dist = sin(deg2rad($latitudeFrom)) * sin(deg2rad($latitudeTo)) +  cos(deg2rad($latitudeFrom)) * cos(deg2rad($latitudeTo)) * cos(deg2rad($theta));
    $dist = acos($dist);
    $dist = rad2deg($dist);
    $miles = $dist * 60 * 1.1515;
    $unit = strtoupper($unit);
    
   if ($unit == "K") {
        echo  ($miles * 1.609344).' km';
    } else if ($unit == "N") {
        echo  ($miles * 0.8684).' nm';
    } else {
        echo  $miles.' mi';
    }

// MySQL Query 
Example:
	(i)	select   1.609344* 3956 * 2 * ASIN(SQRT( POWER(SIN((11.016844 - 11.232103) *  pi()/180 / 2), 2) +COS(11.016844 * pi()/180) * COS(11.232103 * pi()/180) * POWER(SIN((76.955832 - 77.106716) * pi()/180 / 2), 2) )) AS distance 
	(ii)    Select 1.609344 * 3956 * 2 * ASIN(SQRT( POWER(SIN((" . $latitude . " - sa.shop_latitude) *  pi()/180 / 2), 2) +COS(" . $latitude . " * pi()/180) * COS(sa.shop_latitude * pi()/180) * POWER(SIN((" . $longitude . " - sa.shop_longitude) * pi()/180 / 2), 2) )) AS distance