function zoomin() { 
	var z = map.getZoomLevel(); 
	if (z > 0) { 
		map.zoomTo(z - 1); 
	} 
} 
function zoomout() { 
	var z = map.getZoomLevel(); 
	if (z < 16) { 
		map.zoomTo(z + 1); 
	} 
} 

function createMarker(point, icon, html) {
  var marker = new GMarker(point,icon);

  // Show this marker's index in the info window when it is clicked.
  GEvent.addListener(marker, 'click', function() {
  	if (document.getElementById("mappoint_info")) {
  		old_elm = document.getElementById("mappoint_info")
  		if ((document.getElementById("mappoint_info")) == html) {
			document.getElementById("mapholder").removeChild(old_elm);
		}
		else {
			document.getElementById("mapholder").replaceChild(html,old_elm);
		}
  	}
  	else {
		document.getElementById("mapholder").appendChild(html);
	}
  });

  return marker;
}