PHP - output result in ascending order of while() loop

Question

I need to show the result based on the calculations inside of a loop. The result of loop should be ascending order by $distance.

    $sql = "SELECT DISTINCT * FROM cinemas WHERE city='$city'";

    $result = $conn->query($sql);

    if ($result->num_rows > 0) {

        while($row = $result->fetch_assoc()) {



    $lat1 = $_GET['lat'];
    $lon1= $_GET['lon'];
    $lat2 = $row['latitude'];
    $lon2 = $row['longitude'];

    //starting calculating the distance

      $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 = $miles * 1.609344;

    $distance = substr($unit,0,4);
echo $row['cinemaname'].$distance;

}}

How to show the result in ascending order based on the $distance?

It shows as:

cinema name 20 km
cinema name 5 km
cinema name 30 km
cinema name 3 km

I need to show in:

cinema name 3 km
cinema name 5 km
cinema name 20 km
cinema name 30 km

save the values in one array and later sort the array

Rafael Shkembi
– Rafael Shkembi

2016-08-29 08:44:16 +00:00
Commented Aug 29, 2016 at 8:44 — Rafael Shkembi
– Rafael Shkembi, Commented Aug 29, 2016 at 8:44
Thanks for your comment but I have no idea how to do that

J. Doe
– J. Doe

2016-08-29 08:45:23 +00:00
Commented Aug 29, 2016 at 8:45 — J. Doe
– J. Doe, Commented Aug 29, 2016 at 8:45

Provie9 · Accepted Answer · 2016-08-29 08:51:04Z

2

Save the return in the while in a array like this:

$cinema[$i]['cinemaname'] = $row['cinemaname'];
$cinema[$i]['distance'] = $distance;

and make after the while this:

function sortByOrder($a, $b) {
    return $a['distance'] - $b['distance'];
}

usort($cinema, 'sortByOrder');

now you have your order :)

This is your code now:

$sql = "SELECT DISTINCT * FROM cinemas WHERE city='$city'";

$result = $conn->query($sql);
$cinema = array();
$i = 0;
if ($result->num_rows > 0) {

    while($row = $result->fetch_assoc()) {
       $lat1 = $_GET['lat'];
       $lon1= $_GET['lon'];
       $lat2 = $row['latitude'];
       $lon2 = $row['longitude'];

       //starting calculating the distance

       $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 = $miles * 1.609344;

       $distance = substr($unit,0,4);
       $cinema[$i]['cinemaname'] = $row['cinemaname'];
       $cinema[$i]['distance'] = $distance;
       $i++;
    }
}

function sortByOrder($a, $b) {
   return $a['distance'] - $b['distance'];
}

usort($cinema, 'sortByOrder');

edited Aug 29, 2016 at 8:51

answered Aug 29, 2016 at 8:45

Provie9

3792 silver badges14 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

J. Doe Over a year ago

thanks for the answer, but shows empty page. What should I echo here? When I wrote echo to $cinema[$i]['distance'] it showed me not in a ascending order...

Provie9 Over a year ago

what is the output from print_r($cinema) after the usort?

J. Doe Over a year ago

Array ( [0] => Array ( [cinemaname] => 44 [distance] => 2.00 ) [1] => Array ( [cinemaname] => 43 [distance] => 2.34 ) [2] => Array ( [cinemaname] => 47 [distance] => 5.61 ) [3] => Array ( [cinemaname] => 41 [distance] => 6.08 ) [4] => Array ( [cinem...

J. Doe Over a year ago

I need to echo it/print_r it inside of the loop not outside.

J. Doe Over a year ago

the usort and print_r($cinema) should be presented inside of the loop because the name of the cinema is inside but the distance is outside now

Anish Abraham · Accepted Answer · 2016-08-29 09:49:38Z

0

    $sql = "SELECT DISTINCT * FROM cinemas WHERE city='$city'";



       $result = $conn->query($sql);
    $distanceArray=array('');
$i=0;
        if ($result->num_rows > 0) {

        while($row = $result->fetch_assoc()) {



    $lat1 = $_GET['lat'];
    $lon1= $_GET['lon'];
    $lat2 = $row['latitude'];
    $lon2 = $row['longitude'];

    //starting calculating the distance

      $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 = $miles * 1.609344;

    $distance = substr($unit,0,4);
    $distanceArray[$i]=$row['cinemaname'].$distance;
$i++;
}}
sort($distanceArray);
foreach($distanceArray as $nameDistance)
{
echo $nameDistance; echo '<br>';
}

answered Aug 29, 2016 at 9:49

Anish Abraham

2374 silver badges20 bronze badges

5 Comments

J. Doe Over a year ago

Thank you Anish, but what if I have two loops? A while loop inside of the while loop, because there is two selections from two tables...

J. Doe Over a year ago

there are 3 tables:

$sql = "SELECT DISTINCT cinemaname,id FROM cinemas WHERE city='$city' "; $sql2 = "SELECT DISTINCT cinemaname,id,logo FROM cinema WHERE id = '$cinemaname'"; $sql3 = "SELECT DISTINCT * FROM moviecinemashowsassociation WHERE cinemaid = '$cinemaid' AND movieid='$movieid'  AND showdate='$today' ";

Anish Abraham Over a year ago

insert code in between two wile loop , and take array in out side

$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 = $miles * 1.609344;      $distance = substr($unit,0,4);     $distanceArray[$i]=$row['cinemaname'].$distance;

J. Doe Over a year ago

but there are 3 loops... please let me know how I can contact you? Your code works but still in 3 loops I getting confused how to use it...

Anish Abraham Over a year ago

you insert the needed condition in while loop

while( ){while( ){while( ){ $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 = $miles * 1.609344; $distance = substr($unit,0,4); $distanceArray[$i]=$row['cinemaname'].$distance;  }}}

meteorite · Accepted Answer · 2017-01-14 12:37:14Z

0

You can also write a MySQL function to calculate the distance and just query it in ascending order. something like this:

$sql = "SELECT DISTINCT *, distance($lat1,$lon1) AS dist  FROM cinemas WHERE city='$city' ORDER BY dist ASC";

Of course you have to write the corresponding MySQL function beforehand.

answered Jan 14, 2017 at 12:37

meteorite

7661 gold badge8 silver badges17 bronze badges

1 Comment

meteorite Over a year ago

You can check this to calculate the distance in SQL: stackoverflow.com/questions/24370975/…

Collectives™ on Stack Overflow

PHP - output result in ascending order of while() loop

3 Answers 3

5 Comments

5 Comments

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

5 Comments

5 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related