Calculate distance with variable lat and lon values

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nita
Forum Commoner
Posts: 39
Joined: Wed May 02, 2007 5:49 am

Calculate distance with variable lat and lon values

Post by nita »

Hi

I have a problem with implementing variables into a function that calculate distance between 2 latitudes, longitudes.
One of the is constant, and the second one being passed from the form.

Here is the code:

Code: Select all

	$lon1 = $_POST['lon1'];
	$lat1 = $_POST['lat1'];
	$lon2 = '-0.30020239';
	$lat2 = '51.58734910';
	
function distance($lat11, $lon11, $lat22, $lon22) { 
	$theta = $lon11 - $lon22; 
	$dist = sin(deg2rad($lat11)) * sin(deg2rad($lat22)) +  cos(deg2rad($lat11)) * cos(deg2rad($lat22)) * cos(deg2rad($theta)); 
	$dist = acos($dist); 
	$dist = rad2deg($dist); 
	$miles = $dist * 60 * 1.1515;
		return $miles;
}

echo "
$lon1, $lat1<br>
$lon2, $lat2<br>";
//////////  return good calculation
echo distance(52.611644, -0.26304, 51.58734910, -0.30020239) . " miles<br>";

////////// my way - return wrong calculation 
echo distance("$lon1", "$lat1", 51.58734910, -0.30020239) . " miles<br>";
As long as i have lat, lon values hardcoded is fine, but idea is to have this calculation done from variables.
Both will vary .... tried different configurations ... i'm losing it ...

How should I code it ??

Thanks for your help in advance!
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requinix
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Re: Calculate distance with variable lat and lon values

Post by requinix »

We kinda have to the see non-working code to be able to tell you why it's not working.
nita
Forum Commoner
Posts: 39
Joined: Wed May 02, 2007 5:49 am

Re: Calculate distance with variable lat and lon values

Post by nita »

There was a problem in calling a distance() function. Function is defined as lat, lon, lat, lon, but i called it as lon, lat, lon, lat.

Being blind.

SOLVED.
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pickle
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Re: Calculate distance with variable lat and lon values

Post by pickle »

Please update your original post's subject to include [solved], so others know.
Real programmers don't comment their code. If it was hard to write, it should be hard to understand.
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