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diff --git a/includes/geocalc/README b/includes/geocalc/README deleted file mode 100644 index 36391e8..0000000 --- a/includes/geocalc/README +++ /dev/null @@ -1,148 +0,0 @@ -GEOCALC-PHP -Geographic Distance and Azimuth Calculations in PHP -Version 1.2 - - -ABOUT THIS LIBRARY -This code was "ported" to PHP from Visual C++ by Steven Brendtro -of www.imaginerc.com. The original article and source code, written -by andyf4i can be found on CodeGuru.com at the following address: - -http://www.codeguru.com/Cpp/Cpp/algorithms/article.php/c5115/ - - -VERSION HISTORY -Version 1.0 - Initial release -Version 1.1 - Bug in getKMPerLonAtLat() fixed. - Thanks to Eric Iverson for finding it. -Version 1.2 - Bug in getLonPerKMAtLat() fixed. - - -FILES INCLUDED IN THIS RELEASE -GeoCalc.class.php - The actual PHP class -README - This file - - -ADDITIONAL PACKAGES -Also available on SourceForge.net under the GEOCALC-PHP project, -you can find a ZIP Code database (for FREE!) that you can use -for distance calculations between ZIP Codes. - -For increased speed when performing distance calculations using -MySQL, be sure to check out GEOCALC-UDF at SourceForge.net. -This UDF (User Defined Function) is designed for MySQL and has -been known to reduce query time up to 1000%! - - -METHODS - -# Basic Methods: -GeoCalc(); # Default Constructor - -GCDistance($lat1, $lon1, $lat2, $lon2); - # Using the Great Circle formula, calculate - # the distance in kilometers between - # Latitude/Longitude 1 and Latitude/Longitude 2 - -GCAzimuth($lat1, $lon1, $lat2, $lon2); - # Using the Great Circle formula, calculate the - # azimuth between Latitude/Longitude 1 and - # Latitude/Longitude 2 - -ApproxDistance($lat1, $lon1, $lat2, $lon2); - # Using the Ellipsoidal Approximation formula, - # calculate the distance in kilometers between - # Latitude/Longitude 1 and Latitude/Longitude 2 - -EllipsoidDistance($lat1, $lon1, $lat2, $lon2); - # Using the Ellipsoidal Distance formula, calculate - # the distance in kilometers between Latitude/Longitude 1 - # and Latitude/Longitude 2. This formula is the most - # accurate of the formulas. - -# Helper Methods - -getKmPerLonAtLat($dLatitude); - # Get the number of Kilometers per degree longitude - # at the given latitude. - -getLonPerKmAtLat($dLatitude); - # Get the number of degrees longitude per kilometer at the - # given latitude. - -getKmPerLat(); - # Get the number of kilometers per degree latitude (average - # of 111.0 kilometers per degree) - -getLatPerKm(); - # Get the number of degrees latitude per kilometer (average - # of 1/111 degrees per kilometer) - - -# Helper Function (not a method in the class, but a function) - -ConvKilometersToMiles($dValue); - # Convert a distance from kilometers to miles - # (km / 1.609344 = miles). - - -EXAMPLES - -Here are some example uses for this class: - - include_once("GeoCalc.class.php"); - - $oGC = new GeoCalc(); - - // Great Circle Distance - $dDist = $oGC->GCDistance(38.9333,-94.3253,38.9314,-94.4876); - - // Great Circle Azimuth - $dDist = $oGC->GCAzimuth(38.9333,-94.3253,38.9314,-94.4876); - - // Approximate Ellipsoid Distance - $dDist = $oGC->ApproxDistance(38.9333,-94.3253,38.9314,-94.4876); - - // Accurate Ellipsoid Distance - $dDist = $oGC->EllipsoidDistance(38.9333,-94.3253,38.9314,-94.4876); - - // Convert distance from kilometers to miles - $dDistMiles = ConvKilometersToMiles($dDist); - - // Advanced Calculation: - // The following will search for ZIP codes - // within a radius (roughly calculated) - - // Define the center of the search bounds... - $dLongitude = -94.44590241; - $dLatitude = 38.7996; - - // Define the maximum search distance - $dRadius = 100.00; // in kilometers - - // Calculate the boundary distance in degrees longitude / latitude - $dAddLat = $oGC->getLatPerKm() * $dRadius; - $dAddLon = $oGC->getLonPerKmAtLat($dLatitude) * $dRadius; - - // Calculate the boundaries - $dNorthBounds = $dLatitude + $dAddLat; - $dSouthBounds = $dLatitude - $dAddLat; - $dWestBounds = $dLongitude - $dAddLon; - $dEastBounds = $dLongitude + $dAddLon; - - print "Center Longitude: $dLongitude\n"; - print "Center Latitude: $dLatitude\n"; - print "Radius: $dRadius kilometers\n"; - - print "North Bounds: $dNorthBounds\n"; - print "South Bounds: $dSouthBounds\n"; - print "East Bounds: $dEastBounds\n"; - print "West Bounds: $dWestBounds\n"; - - // Sample SQL query stament based on above boundaries: - $strQuery = "SELECT * FROM PostalCodes " . - "WHERE Latitude > $dSouthBounds " . - "AND Latitude < $dNorthBounds " . - "AND Longitude > $dWestBounds " . - "AND Longitude < $dEastBounds"; - |