title: How to change the zoom level of Google maps programmatically?
body: <pre><code>function displayMapAndClick ()
      {
          var latlng    = new google.maps.LatLng (29.0167, 77.3833);
          var myOptions = 
          {
              zoom:zm,
              center:latlng,
              mapTypeId:google.maps.MapTypeId.ROADMAP
          };
  
          map = new google.maps.Map (document.getElementById (&quot;map&quot;), myOptions);
          directionsDisplay.setMap (map); 
      }
  </code></pre>
  <p>Where <code>zm</code>  is a global variable set to default <code>7</code>.</p>
  <p>Now, I wish to change the zoom level of this map thorough this program.</p>
  <p>What is the way to do that without re-initializing the map, or is re-initializing the map compulsory?</p>