Multidimensional arrays for newbies

powelly · May 4, 2007

This is driving me nuts I just cant seem to get my head around it.

I run a query to select some information from a table, then I loop through each of the records returned performing a calculation on one of the fields.

I need to display the results sorted by the result of the calculation so I need to insert the returned results into an array.

//fill array
$Location_Distances_md_array[] = array($row[1] => $distance);

then once the loop finishes I want to display the content of the array sorted by the $distance, but Im lost here, I just cant get my head around it.

This is what I have so far

<? include 'db.php' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Untitled Document</title>
</head>

<body>
<?php

// to use this grab the SQL database of postcodes from www.pjenkins.co.uk/uk_postcodes

function getDistance($lat1, $long1, $lat2, $long2)
{
//$earth = 6371; //km change accordingly
$earth = 3960; //miles

//Point 1 cords
$lat1 = deg2rad($lat1);
$long1= deg2rad($long1);

//Point 2 cords
$lat2 = deg2rad($lat2);
$long2= deg2rad($long2);

//Haversine Formula
$dlong=$long2-$long1;
$dlat=$lat2-$lat1;

$sinlat=sin($dlat/2);
$sinlong=sin($dlong/2);

$a=($sinlat*$sinlat)+cos($lat1)*cos($lat2)*($sinlong*$sinlong);

$c=2*asin(min(1,sqrt($a)));

$d=round($earth*$c);

return $d;
}

if($_POST)
{
mysql_connect($host,$user,$pass);
@mysql_select_db($db) or die( "Unable to select database");

$firstpc = strtoupper(preg_replace("/[^a-zA-Z0-9]/","", $_POST[first]));
$secondpc = strtoupper(preg_replace("/[^a-zA-Z0-9]/","", $_POST[second]));

$query = 'SELECT `Lat`, `Long` FROM `UKPostCodes` WHERE `PostCode`="'.$firstpc.'";';
$result = mysql_query($query);
$first = mysql_fetch_row($result);



// set database server access variables:

// open connection
$connection = mysql_connect($host, $user, $pass) or die ("Unable to connect!");

// select database
mysql_select_db($db) or die ("Unable to select database!");

// create query
$query = "SELECT * FROM `Locations`;";

// execute query
$result = mysql_query($query) or die ("Error in query: $query. ".mysql_error());

// see if any rows were returned
if (mysql_num_rows($result) > 0) {
    // yes
    // print them one after another
        
  
    
    while($row = mysql_fetch_row($result)) {

        	echo "<tr>";

		$query2 = 'SELECT `Lat`, `Long` FROM `UKPostCodes` WHERE `PostCode`="'.$row[2].'";';
		$result2 = mysql_query($query2);
		$second = mysql_fetch_row($result2);

		//calculate distance
		$distance = getDistance($first[0], $first[1], $second[0], $second[1])." miles.";
        	
		//fill array
		$Location_Distances_md_array[] = array($row[0] => $distance);

		//echo data
		echo $row[0]." ".$row[1]." ".$row[3]." ".$distance."<br>";   
        
    }
  
}
else {
    // no
    // print status message
    echo "<p align='center'><font color='#808080' face='Arial'>No records found.</font></p>
";
}


mysql_close();

echo "<br>";
}


for ( $row = 0; $row < 10; $row++ )
{
for ( $column = 0; $column < 10; $column++ )
{
  echo $Location_Distances_md_array[$row][$column];
}
echo '<br />';
}

?>

<form action="index.php" method="post">
Only enter the first part of the postcode. If your postcode is TS20 3DS, just enter the TS20.<br /><br />
First Postcode: <input name="first" maxlength="4" /><br />
<br />
<input type="submit" />
</form>

</body>
</html>

Barand · May 4, 2007

Can you post the output from

var_export($Location_Distances_md_array);

Sign In

Multidimensional arrays for newbies

Recommended Posts

powelly

Link to comment

Share on other sites

Barand

Link to comment

Share on other sites

Archived

Browse

Activity

Important Information