code: function (dimName, axisIndex, dataZoomModel, ecModel) {
  
      /**
       * @private
       * @type {string}
       */
      this._dimName = dimName;
  
      /**
       * @private
       */
      this._axisIndex = axisIndex;
  
      /**
       * @private
       * @type {Array.<number>}
       */
      this._valueWindow;
  
      /**
       * @private
       * @type {Array.<number>}
       */
      this._percentWindow;
  
      /**
       * @private
       * @type {Array.<number>}
       */
      this._dataExtent;
  
      /**
       * {minSpan, maxSpan, minValueSpan, maxValueSpan}
       * @private
       * @type {Object}
       */
      this._minMaxSpan;
  
      /**
       * @readOnly
       * @type {module: echarts/model/Global}
       */
      this.ecModel = ecModel;
  
      /**
       * @private
       * @type {module: echarts/component/dataZoom/DataZoomModel}
       */
      this._dataZoomModel = dataZoomModel;
  
      // /**
      //  * @readOnly
      //  * @private
      //  */
      // this.hasSeriesStacked;
  }
docs: Operate single axis.
  One axis can only operated by one axis operator.
  Different dataZoomModels may be defined to operate the same axis.
  (i.e. 'inside' data zoom and 'slider' data zoom components)
  So dataZoomModels share one axisProxy in that case.
  
  @class