## Distance calculation based on multiple locations (Lat,Lon)

Codes here !

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nitapita
New php-forum User
Posts: 8
Joined: Sun Jan 06, 2013 12:41 am
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I would like to calculate the total distance of driving beetween multiple locations (loop), including the distance (starting point (garage) - first location sarting point) and (last location finishig point - finishing point (garage)). Example: (Garage + D1) + (D1 + D2) + (D2 + E1) + (E1 + E2) + E2 + Garage)

I'm having a problem with the correct looping. Here's my simplified code:

Code: Select all

``````<?
\$driver = 5;

\$result2 = mysql_query("SELECT * FROM test WHERE id='\$driver' LIMIT 1") or die(mysql_error());
while(\$row2 = mysql_fetch_array( \$result2 )) {
\$lon=\$row2['lon'];
\$lat=\$row2['lat'];
echo "\$lon, \$lat";
}

\$result = mysql_query("SELECT * FROM test1 WHERE driver='\$driver'") or die(mysql_error());
while(\$row = mysql_fetch_array( \$result )) {

\$lon1=\$row['lon1'];
\$lat1=\$row['lat1'];
\$lon2=\$row['lon2'];
\$lat2=\$row['lat2'];

\$distancecalc = (3958*3.1415926*sqrt((\$lat-\$lat1)*(\$lat-\$lat1) + cos(\$lat/57.29578)*cos(\$lat1/57.29578)*(\$lon-\$lon1)*(\$lon-\$lon1))/180);
\$distancecalc1 = \$distancecalc1 + (3958*3.1415926*sqrt((\$lat2-\$lat1)*(\$lat2-\$lat1) + cos(\$lat2/57.29578)*cos(\$lat1/57.29578)*(\$lon2-\$lon1)*(\$lon2-\$lon1))/180);
\$distancecalc2 = (3958*3.1415926*sqrt((\$lat2-\$lat)*(\$lat2-\$lat) + cos(\$lat2/57.29578)*cos(\$lat/57.29578)*(\$lon2-\$lon)*(\$lon2-\$lon))/180);

\$distancetotal = \$distancecalc + \$distancecalc1 +\$distancecalc2;

echo "\$distancecalc<br>
\$distancecalc1<br>
\$distancecalc2<br>";
}
echo "\$distancetotal";
?>
``````
I'm aware that code posted above doesnt't do what it meant to .. i just want to keep it clear.. there is some things i tried but no correct resoults.

I would appreciate some help on this one.

Thank you very much.

nitapita
New php-forum User
Posts: 8
Joined: Sun Jan 06, 2013 12:41 am
Ok. I worked it out with help of mac_gyver (php freaks). All calculations are done as i wish. My code below:

Code: Select all

``````<?
include "connectdb.php";
\$driver = 5;
\$datestamp = '2013/05/07';
\$result2 = mysql_query("SELECT * FROM drivers WHERE id='\$driver' LIMIT 1") or die(mysql_error());
while(\$row2 = mysql_fetch_array( \$result2 )) {
\$lon=\$row2['lon'];
\$lat=\$row2['lat'];
}

\$result = mysql_query("SELECT * FROM quotedb WHERE moveday='\$datestamp' AND driver='\$driver' AND cleared='Not Cleared' AND status='Done' ORDER BY moveday, timeday") or die(mysql_error());
\$distance = 0; // accumulate the distance
\$first_pass = true; // flag to detect the first row inside the loop
while(\$row = mysql_fetch_assoc( \$result )) {
\$lon2a=\$lon2;
\$lat2a=\$lat2;
\$lon1=\$row['lon1'];
\$lat1=\$row['lat1'];
\$lon2=\$row['lon2'];
\$lat2=\$row['lat2'];
// calculate the distance from the Garage to the first point of the first row
if(\$first_pass){
\$distance += (3958*3.1415926*sqrt((\$lat-\$lat1)*(\$lat-\$lat1) + cos(\$lat/57.29578)*cos(\$lat1/57.29578)*(\$lon-\$lon1)*(\$lon-\$lon1))/180);
\$first_pass = false;
}
// calculate the distance for each row (segment) in the route
\$distance += (3958*3.1415926*sqrt((\$lat2-\$lat1)*(\$lat2-\$lat1) + cos(\$lat2/57.29578)*cos(\$lat1/57.29578)*(\$lon2-\$lon1)*(\$lon2-\$lon1))/180);
if ( \$lon2a == "" and \$lat2a =="" ) {
} else {
// calculate the distance from the second point of the first row to the first point of the next row
\$distance += (3958*3.1415926*sqrt((\$lat2a-\$lat1)*(\$lat2a-\$lat1) + cos(\$lat2a/57.29578)*cos(\$lat1/57.29578)*(\$lon2a-\$lon1)*(\$lon2a-\$lon1))/180);
}
}
// calculate the distance from the second point of the last row to the Garage
\$distance += (3958*3.1415926*sqrt((\$lat2-\$lat)*(\$lat2-\$lat) + cos(\$lat2/57.29578)*cos(\$lat/57.29578)*(\$lon2-\$lon)*(\$lon2-\$lon))/180);
echo "\$distance<br>
";
?>
``````
Still think there is a place for improvement in the code. Will aplay Haversine method for calculations. Do you guys have some suggestion to improve this piece of code ... thx