docs: function ChartAxes () {
      var axesLinker = function (scope, element, attrs, chartCtrl) {
          var x = attrs.valuesX;
          if (x) {
              chartCtrl.addXAxisValues(x);
          }
  
          var xs = attrs.valuesXs;
          var xsValues = {};
          if (xs) {
              xsItems = xs.split(",");
              for (var xsI in xsItems) {
                  xsItem = xsItems[xsI].split(":");
                  xsValues[xsItem[0]] = xsItem[1];
              }
              chartCtrl.addXSValues(xsValues);
          }
  
          var y = attrs.y;
          var y2 = attrs.y2;
          var yAxis = {};
          if (y2) {
              var items = y2.split(",");
              for (var item in items) {
                  yAxis[items[item]] = "y2";
              }
              if (y) {
                  var yItems = y.split(",");
                  for (var yItem in yItems) {
                      yAxis[yItems[yItem]] = "y";
                  }
              }
              chartCtrl.addYAxis(yAxis);
          }
      };
  
      return {
          "require": "^c3chart",
          "restrict": "E",
          "scope": {},
          "replace": true,
          "link": axesLinker
      };
  }