Where to write map.checkResize();

Question

In google map code, where to write map.checkResize() ? My code is

       var map = new GMap2(document.getElementById("map_canvas"), { googleBarOptions:{ onGenerateMarkerHtmlCallback: doGenerateMarkerHtmlCallback, showOnLoad: true }
        });
             marker = new GMarker(new GLatLng(lat, lon)); 
            var topRight = new GControlPosition(G_ANCHOR_TOP_RIGHT, new GSize(20, 40));
            map.addControl(new GLargeMapControl3D(), topRight);
            map.setCenter(new GLatLng(lat, lon), 5);

            map.addOverlay(marker);