/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.cassandra.utils;
import java.util.Iterator;
public abstract class AbstractStatsDeque implements Iterable<Double>
{
public abstract Iterator<Double> iterator();
public abstract int size();
public abstract void add(double o);
public abstract void clear();
//
// statistical methods
//
public double sum()
{
double sum = 0d;
for (Double interval : this)
{
sum += interval;
}
return sum;
}
public double sumOfDeviations()
{
double sumOfDeviations = 0d;
double mean = mean();
for (Double interval : this)
{
double v = interval - mean;
sumOfDeviations += v * v;
}
return sumOfDeviations;
}
public double mean()
{
return sum() / size();
}
public double variance()
{
return sumOfDeviations() / size();
}
public double stdev()
{
return Math.sqrt(variance());
}
}