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@Koc
Created June 29, 2012 08:42
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Doctrine2 DISTANCE function
<?php
namespace Myako\Geographical\Functions;
use Doctrine\ORM\Query\AST\Functions\FunctionNode;
use Doctrine\ORM\Query\Lexer;
/**
* "DISTANCE" "(" LatitudeFrom, LongitudetFrom, LatitudeTo, LongitudeTo ")"
*
* @author Konstantin.Myakshin <koc-dp@yandex.ru>
*/
class DistanceFunction extends FunctionNode
{
protected $fromLat;
protected $fromLng;
protected $toLat;
protected $toLng;
public function parse(\Doctrine\ORM\Query\Parser $parser)
{
$parser->match(Lexer::T_IDENTIFIER);
$parser->match(Lexer::T_OPEN_PARENTHESIS);
$this->fromLat = $parser->ArithmeticPrimary();
$parser->match(Lexer::T_COMMA);
$this->fromLng = $parser->ArithmeticPrimary();
$parser->match(Lexer::T_COMMA);
$this->toLat = $parser->ArithmeticPrimary();
$parser->match(Lexer::T_COMMA);
$this->toLng = $parser->ArithmeticPrimary();
$parser->match(Lexer::T_CLOSE_PARENTHESIS);
}
public function getSql(\Doctrine\ORM\Query\SqlWalker $sqlWalker)
{
$earthDiameterInKM = 1.609344 * 3956 * 2;
$sql = '('.$earthDiameterInKM.' * ASIN(SQRT(POWER(' .
'SIN(('.$this->fromLat->dispatch($sqlWalker).' - ABS('.$this->toLat->dispatch($sqlWalker).')) * PI() / 180 / 2), 2) + ' .
'COS('.$this->fromLat->dispatch($sqlWalker).' * PI() / 180) * COS(ABS('.$this->toLat->dispatch($sqlWalker).') * PI() / 180) * ' .
'POWER(SIN(('.$this->fromLng->dispatch($sqlWalker).' - '.$this->toLng->dispatch($sqlWalker).') * PI() / 180 / 2), 2) ' .
')))';
return $sql;
}
}
@mattmeye
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i think you have to use ArithmeticExpression() instead of ArithmeticPrimary()

@see https://github.com/craue/CraueGeoBundle/blob/master/Doctrine/Query/Mysql/GeoDistance.php#L38

@derWebdesigner
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Important: This function is currently wrong and won't work for any negative latitudes. The ABS-functions need to be removed and then it seems to work correctly. I compared it with the original formula for this calculation and there were no ABS-functions used. I am not sure if there is a good reason why you did use them, but after trying a lot of different geo positions and searching for this error for a few hours now I found out that removing them solves the issue.

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