code: function () {
  
                  // 300,200 A150,50 0 1,0 450,50
                  var path = getArc(150, 150, 0, 1, 0, {x: 275, y:125}, {x:125, y:150});
  
                  console.log(path[0]);
                  $('#path').attr('d', contour2svg(path));
              }
docs: 初始化