title: How to change the radius of the circle around the marker in Google Map API
body: <p>I am trying to change the circle radius  by changing the value of combo-menu. So I wrote the a function for onchange as below.</p>
  
  <pre><code>    function changeRadius(){ 
         var selectedRadius = (document.getElementById("circle_radius").value)*1000;
  
         var circle = new google.maps.Circle({
                map: map,
                radius: selectedRadius // radius unit is meter.
              });
  
         var marker2 = new google.maps.Marker({
                map: map,
                position: new google.maps.LatLng(40,-90),
                draggable: true,
                title: 'Drag me!'
              });
  
         circle1.bindTo('center', marker2, 'position'); 
  
     }
  </code></pre>
  
  <p>But It doesn't work. Any idea?</p>