code: function loadData(dataUrl, jsonEditor) {
  
      // jQuery getJSON will read the file from a Web resources.
      $.getJSON(dataUrl, function(data) {
      //$.getJSON('data/simple-zoomable-circle.json', function(data) {
          // set data to JSON editor.
          jsonEditor.set(data);
          // update the JSON source code
          $('#jsonstring').html(JSON.stringify(data, null, 2));
          // remove the existing one.
          $('#svgpreview').empty();
          // build the circles...
          var options = {
            "margin":10,
            "diameter":500
          };
          $("#svgpreview").zoomableCircles(options, data);
          //console.log(JSON.stringify(data));
      });
  }
docs: load data from the given url, set it to JSON editor and load
  the zoomable circles.