{
  "name" : "sqrt",
  "value" : [[0, 0.3],[1, 1], [2, 1.414], [3, 1.73], [4, 2]]
}

  function plot_async() {
    var url = 'data.json';
    var d = loadJSONDoc(url);
    var gotData = function (data) {
    var layout = new Layout("bar");
      layout.addDataset(data.name, data.value);
      layout.evaluate();

    var chart = new SweetCanvasRenderer($("chart"), layout);
    chart.render();  
    };
    var dataFetchFailed = function (err) {
      alert("data not found");
    };
    d.addCallbacks(gotData, dataFetchFailed);
  }