http://requirejs.org/docs/errors.html#notloaded
希望各位能帮我解答一下困惑，谢谢。
var deps = [
"underscore",
"/viz.js"
];
require( deps, function(mvc, _) {
drawGraph();
});
function drawGraph(){
var g = "digraph G { a1 -> b3; b2 -> a3; a3 -> a0; }";
var tt=Viz(g,"svg");
}
