content: /*
   * Tencent is pleased to support the open source community by making Angel available.
   *
   * Copyright (C) 2017-2018 THL A29 Limited, a Tencent company. All rights reserved.
   *
   * 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
   *
   * https://opensource.org/licenses/Apache-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.
   *
   */
  package com.tencent.angel.sona.tree.stats.quantile;
  
  import java.io.Serializable;
  
  public abstract class QuantileSketch implements Serializable {
      // total number of data items appeared
      protected long n;
      // estimated total number of data items there will be,
      // if not -1, sufficient space will be allocated at once
      protected long estimateN;
  
      protected float minValue;
      protected float maxValue;
  
      public QuantileSketch(long estimateN) {
          this.estimateN = estimateN > 0 ? estimateN : -1L;
      }
  
      public QuantileSketch() {
          this(-1L);
      }
  
      public abstract void reset();
  
      public abstract void update(float value);
  
      public abstract void merge(QuantileSketch other);
  
      public abstract float getQuantile(float fraction);
  
      public abstract float[] getQuantiles(float[] fractions);
  
      public abstract float[] getQuantiles(int evenPartition);
  
      public abstract float[] tryDistinct(int maxItemNums);
  
      public boolean isEmpty() {
          return n == 0;
      }
  
      public long getN() {
          return n;
      }
  
      public long getEstimateN() {
          return estimateN;
      }
  
      public float getMinValue() {
          return minValue;
      }
  
      public float getMaxValue() {
          return maxValue;
      }
  }