Just a note to keep in the back of your mind. Unless I'm mistaken MapQuest prints out road miles to a location. The formula prints out direct (or as the crow flies) miles. There will almost always be differences between the two. Fred Steinkopf ----- Original Message ----- From: "Aaron Gould" <[EMAIL PROTECTED]> To: "Edward Peloke" <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]> Sent: Friday, November 15, 2002 11:49 AM Subject: Re: [PHP] longitude/latitude function
> I got that from http://freshmeat.net/projects/zipdy/?topic_id=66. It's a > program called Zipdy that does these calculations. There's also a similar > function on the US government census site (can't remember where though), but > I liked Zipdy's better. > > -- > Aaron Gould > [EMAIL PROTECTED] > Web Developer > Parts Canada > > > ----- Original Message ----- > From: "Edward Peloke" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Friday, November 15, 2002 11:55 AM > Subject: RE: [PHP] longitude/latitude function > > > > Thanks Aaron, > > > > If you don't mind me asking, where did you get it? It seems to give a > > better answer than my function. > > > > Thanks! > > Eddie > > > > -----Original Message----- > > From: Aaron Gould [mailto:[EMAIL PROTECTED]] > > Sent: Friday, November 15, 2002 11:04 AM > > To: Edward Peloke; [EMAIL PROTECTED] > > Subject: Re: [PHP] longitude/latitude function > > > > > > Try this snippet... I can't vouch for its accuracy since I am not a > > mathematician: > > > > <? > > // Function takes latitude and longitude of two places as input > > // and prints the distance in miles and kms. > > function calculateDistance($lat1, $lon1, $lat2, $lon2) > > // Convert all the degrees to radians > > $lat1 = deg2rad($lat1); > > $lon1 = deg2rad($lon1); > > $lat2 = deg2rad($lat2); > > $lon2 = deg2rad($lon2); > > > > // Find the deltas > > $delta_lat = $lat2 - $lat1; > > $delta_lon = $lon2 - $lon1; > > > > // Find the Great Circle distance > > $temp = pow(sin($delta_lat / 2.0), 2) + cos($lat1) * cos($lat2) * > > pow(sin($delta_lon / 2.0), 2); > > > > $EARTH_RADIUS = 3956; > > > > $distance = ($EARTH_RADIUS * 2 * atan2(sqrt($temp), sqrt(1 - $temp)) * > > 1.6093); > > > > return $distance; > > } > > ?> > > > > > > -- > > Aaron Gould > > [EMAIL PROTECTED] > > Web Developer > > Parts Canada > > > > > > ----- Original Message ----- > > From: "Edward Peloke" <[EMAIL PROTECTED]> > > To: <[EMAIL PROTECTED]> > > Sent: Friday, November 15, 2002 11:20 AM > > Subject: [PHP] longitude/latitude function > > > > > > > Has anyone ever written a php function to take the longitude and > latitude > > of > > > two destinations and calculate the distance? > > > > > > I am working on one but the output is just a little off. > > > > > > Thanks, > > > Eddie > > > > > > > > > -- > > > PHP General Mailing List (http://www.php.net/) > > > To unsubscribe, visit: http://www.php.net/unsub.php > > > > > > -- > > PHP General Mailing List (http://www.php.net/) > > To unsubscribe, visit: http://www.php.net/unsub.php > > > > > > -- > > PHP General Mailing List (http://www.php.net/) > > To unsubscribe, visit: http://www.php.net/unsub.php > > > -- > PHP General Mailing List (http://www.php.net/) > To unsubscribe, visit: http://www.php.net/unsub.php > -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
