org.apache.hadoop.hbase.util

类 RollingStatCalculator

java.lang.Object

org.apache.hadoop.hbase.util.RollingStatCalculator

@InterfaceAudience.Private
public class RollingStatCalculator
extends Object

This class maintains mean and variation for any sequence of input provided to it. It is initialized with number of rolling periods which basically means the number of past inputs whose data will be considered to maintain mean and variation. It will use O(N) memory to maintain these statistics, where N is number of look up periods it was initialized with. If zero is passed during initialization then it will maintain mean and variance from the start. It will use O(1) memory only. But note that since it will maintain mean / variance from the start the statistics may behave like constants and may ignore short trends. All operations are O(1) except the initialization which is O(N).

构造器概要

构造器

构造器和说明
RollingStatCalculator(int rollingPeriod) Creates a RollingStatCalculator with given number of rolling periods.

方法概要

限定符和类型	方法和说明
double	getDeviation()
double	getMean()
void	insertDataValue(long data) Inserts given data value to array of data values to be considered for statistics calculation

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

构造器详细资料

RollingStatCalculator

public RollingStatCalculator(int rollingPeriod)

Creates a RollingStatCalculator with given number of rolling periods.

参数:

rollingPeriod -

方法详细资料

insertDataValue

public void insertDataValue(long data)

Inserts given data value to array of data values to be considered for statistics calculation

参数:

data -

getMean

public double getMean()

返回:

mean of the data values that are in the current list of data values

getDeviation

public double getDeviation()

返回:

deviation of the data values that are in the current list of data values