/*
 * Copyright 2007 Google Inc.
 *
 * 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.
 */
package com.google.test.metric;


public class WeightedAverage {

  public static final double WEIGHT = 0.3;
  private final double weight;
  private double overallSum = 0;
  private double overallSqr = 0;

  public WeightedAverage() {
    this(WEIGHT);
  }

  public WeightedAverage(double weight) {
    this.weight = weight;
  }

  public void addValue(long value) {
    overallSqr += Math.pow(value, weight + 1);
    overallSum += Math.pow(value, weight);
  }

  public double getAverage() {
    return overallSqr / overallSum;
  }

  @Override
  public String toString() {
    return String.format("%.2f / %.2f = %.2f", overallSqr, overallSum, getAverage());
  }
}