register = function( cytoscape, jq ){

    if( !cytoscape || !jq ){ return; } // can't register if cytoscape unspecified

    $ = jq;

    cytoscape( 'core', 'navigator', function( options ){
      var cy = this;

      return new Navigator( cy, options );
    } );

  }
Zooms graph.

@this {cytoscapeNavigator}
@param {number} zoomRate The zoom rate value. 1 is 100%.