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Determine if Lat / Lng in Bounds

I am interested in determining if the lat / lng location is within and looking for recommendations on the algorithm. (javascript or php)

Here is what I still have:

var lat = somelat;
var lng = somelng;

if (bounds.southWest.lat < lat && lat < bounds.northEast.lat && bounds.southWest.lng < lng && lng < bounds.northEast.lng) {
     'lat and lng in bounds
}

will it work? thank

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3 answers

A simple comparison in your post will work for US coordinates. However, if you need a solution that is safe to check on the International Date Line (where longitude is ± 180 °):

function inBounds(point, bounds) {
    var eastBound = point.long < bounds.NE.long;
    var westBound = point.long > bounds.SW.long;
    var inLong;

    if (bounds.NE.long < bounds.SW.long) {
        inLong = eastBound || westBound;
    } else {
        inLong = eastBound && westBound;
    }

    var inLat = point.lat > bounds.SW.lat && point.lat < bounds.NE.lat;
    return inLat && inLong;
}
+14
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As you asked about Javascript and PHP (and I needed it in PHP), I turned CheeseWarlock into a great answer to PHP. Which, as usual with PHP, is much less elegant. :)

function inBounds($pointLat, $pointLong, $boundsNElat, $boundsNElong, $boundsSWlat, $boundsSWlong) {
    $eastBound = $pointLong < $boundsNElong;
    $westBound = $pointLong > $boundsSWlong;

    if ($boundsNElong < $boundsSWlong) {
        $inLong = $eastBound || $westBound;
    } else {
        $inLong = $eastBound && $westBound;
    }

    $inLat = $pointLat > $boundsSWlat && $pointLat < $boundsNElat;
    return $inLat && $inLong;
}
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, mysql mysql, , lat SQL.

CheeseWarlock Chris Rae , ,

select inBounds("58.25173","-100.21041","89.71691425364952","180","-88.9294031317244","-180")

and you can call this function in the query like this

DELIMITER $$
CREATE FUNCTION inBounds(pointLat FLOAT, pointLong FLOAT, boundsNElat FLOAT, boundsNElong FLOAT, boundsSWlat FLOAT, boundsSWlong FLOAT) RETURNS VARCHAR(30)
 BEGIN
  DECLARE westBound FLOAT ;
  DECLARE eastBound FLOAT ;
  DECLARE inLong FLOAT DEFAULT 0 ;
  DECLARE inLat FLOAT DEFAULT 0 ;
  IF (pointLong < boundsNElong) THEN 
    SET eastBound = 1;
  End if;
  IF (pointLong > boundsSWlong) THEN
    SET westBound = 1;
  End if;

  IF (boundsNElong < boundsSWlong) THEN
      IF (eastBound || westBound) THEN
         SET inLong = 1;
     END if;
  ELSE 
     IF (eastBound && westBound) THEN 
         SET inLong = 1;
     END IF;
  END IF;
  IF (pointLat > boundsSWlat && pointLat < boundsNElat) THEN
    SET inLat = 1;
  END IF;
  RETURN inLat && inLong;
END$$
DELIMITER ;
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