<?xml version="1.0" encoding="UTF-8"?>
<table xmlns="http://query.yahooapis.com/v1/schema/table.xsd">
  <meta>
    <sampleQuery>SELCT * from {table} WHERE place1="paris" and place2="london"</sampleQuery>
    <author>Adrian Statescu</author>
    <documentationURL></documentationURL>  
    <description>Gives you the distance of two places on earth in miles or kilometers.</description>
  </meta>
  <bindings>
    <select itemPath="" produces="XML">
      <inputs>
        <key id='place1' type='xs:string' paramType='variable' required="true" />
        <key id='place2' type='xs:string' paramType='variable' required="true" />
      </inputs>
      <execute><![CDATA[
         default xml namespace = "http://where.yahooapis.com/v1/schema.rng";
         var out = '';
         var res1 = y.query('select * from geo.places(1) where text="'+place1+'"').results;
         var res2 = y.query('select * from geo.places(1) where text="'+place2+'"').results;
         var lat1 = res1.place.centroid.latitude;
         var lon1 = res1.place.centroid.longitude;
         var lat2 = res2.place.centroid.latitude;
         var lon2 = res2.place.centroid.longitude;
         var d = distance(lat1,lon1,lat2,lon2);

           //computing distance using latitude and longitude coordinates
           function distance(lat1,lon1,lat2,lon2) {

                //earth diameter in miles
                var R = 3960.0;

                //convert latitude and longitude to spherical coordinates in radians
                //phi = 90 - latitude
                var phi_1 = (90.0 - lat1)*Math.PI / 180.0;

                var phi_2 = (90.0 - lat2)*Math.PI / 180.0;

                var theta_1 = lon1 * Math.PI / 180.0;

                var theta_2 = lon2 * Math.PI / 180.0;

                //compute spherical distance from spherical coordinates
                var d = R * Math.acos(

                    Math.sin(phi_1) *

                    Math.sin(phi_2) *

                    Math.cos(theta_1 - theta_2) +

                    Math.cos(phi_1) *

                    Math.cos(phi_2)
                 );

           return d;

         }//end function

             var miles = Math.round(d);
             var kilometers = Math.round(1.609344*d); 
             response.object = <distance>
             <miles>{miles}</miles> 
             <kilometers>{kilometers}</kilometers> 
             {res1.place}{res2.place}
             </distance>
      ]]></execute>
    </select>
  </bindings>
</table>