text: /* Copyright (C) 2016-2018 Alibaba Group Holding Limited
  
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
  
      http://www.apache.org/licenses/LICENSE-2.0
  
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
  ==============================================================================*/
  
  /*
   * Copyright 1999-2018 Alibaba Group.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
  */
  
  #pragma once
  
  #include "xdl/data_io/op/feature_op/single_feature_op/single_feature/single_feature.h"
  
  namespace xdl {
  namespace io {
  
  class StatisFeature : public SingleFeature {
   public:
    virtual void Init(TransformKeyFunc transform_key_func,
                      TransformValueFunc transform_value_func,
                      StatisValueFunc statis_value_func,
                      bool is_average = false) override;
    virtual bool Transform(const ExprNode *source_node, ExprNode *result_node) override;
  
   protected:
    float Statis(const ExprNode *source_node, int64_t &key);
  };
  
  }  // namespace io
  }  // namespace xdl
  