code: function (defaultOptions, elemOptions, legendOptions) {
              var self = this;
              var options = $.extend(true, {}, defaultOptions, elemOptions);
              if (options.value !== undefined) {
                  if ($.isArray(legendOptions)) {
                      for (var i = 0; i < legendOptions.length; ++i) {
                          options = $.extend(true, {}, options, self.getLegendSlice(options.value[i], legendOptions[i]));
                      }
                  } else {
                      options = $.extend(true, {}, options, self.getLegendSlice(options.value, legendOptions));
                  }
              }
              return options;
          }
docs: /*
  Get element options by merging default options, element options and legend options
  @param defaultOptions
  @param elemOptions
  @param legendOptions