Package etomica.data

Class AccumulatorAverageCollapsing

java.lang.Object

etomica.data.DataProcessor

etomica.data.DataProcessorForked

etomica.data.DataAccumulator

etomica.data.AccumulatorAverage

etomica.data.AccumulatorAverageCollapsing

All Implemented Interfaces:

DataPipe, DataPipeForked, IDataSink, IDataSource

public class AccumulatorAverageCollapsing
extends AccumulatorAverage

AccumulatorAverage that adjusts the block size during the simulation. When a certain number of blocks of data have been collected, the blocks are collapsed such that each new block contains the data from two of the old blocks. In other words, with each collapse, the number of blocks currently holding data is cut in half and the size of each block is doubled.

This allows the accumulator to yield reasonable estimates of the average and uncertainty during the beginning of the simulation and still produce accurate estimates of the uncertainty for longer simulation runs.

This accumulator can only operate on Data with a single value.

Nested Class Summary

Nested classes/interfaces inherited from class etomica.data.AccumulatorAverage

AccumulatorAverage.StatType

Field Summary

Fields

Modifier and Type	Field	Description
protected double[]	blockAvgs
protected double	correlationSum
protected double	currentBlockAvg
protected int	maxBlocks
protected long	nominalBlockSize
protected double	totalAvg
protected double	totalBlockAvg
protected double	totalBlockVarSum
protected double	totalSumSquare
protected double	totalVarSum

Fields inherited from class etomica.data.AccumulatorAverage

average, AVERAGE, BLOCK_CORRELATION, blockCorrelation, blockCountDown, blockSize, count, dataGroup, doIncludeACInError, error, ERROR, MOST_RECENT, mostRecent, STANDARD_DEVIATION, standardDeviation

Fields inherited from class etomica.data.DataAccumulator

active, hasUnpushedData, pushInterval, putCount

Fields inherited from class etomica.data.DataProcessor

dataInfo, dataSink, tag

Constructor Summary

Constructors

Constructor	Description
AccumulatorAverageCollapsing()	Default constructor sets the maximum number of blocks (maxBlocks) to a default value of 20, the initial block size (blockSize) to 1 and the interval for pushing the output data (pushInterval) to 100.
AccumulatorAverageCollapsing(int maxBlocks)	Constructor with default pushInterval of 100 and initial blockSize of 1.
AccumulatorAverageCollapsing(int maxBlocks, int blockSize)	Constructor with default pushInterval of 100.

Method Summary

Modifier and Type	Method	Description
boolean	addData(IData data)	Add the given values to the sums and block sums.
protected void	collapseBlocks()
protected void	doBlockSum()	Performs the block sum after blockSize calls to addData.
IData	getData()
int	getMaxBlocks()
IDataInfo	processDataInfo(IDataInfo incomingDataInfo)	Prepares the accumulator for input data.
void	reset()	Resets all sums to zero.
void	setBlockSize(long newBlockSize)	Sets the size of the block used to group data for error analysis.
void	setMaxBlocks(int newMaxBlocks)	Changes the maximum number of blocks.

Methods inherited from class etomica.data.AccumulatorAverage

addDataSink, doIncludeACInError, getBlockCount, getBlockSize, getData, getSampleCount, getTag, setIncludeACInError, statChoices

Methods inherited from class etomica.data.DataAccumulator

getPushInterval, isActive, processData, setActive, setPushInterval, toString

Methods inherited from interface etomica.data.DataPipe

getTag

Methods inherited from class etomica.data.DataProcessor

getDataInfo, getTag, putData, putDataInfo

Methods inherited from class etomica.data.DataProcessorForked

addDataSink, getDataSink, getDataSinks, removeDataSink, setDataSink, setDataSinks

Methods inherited from interface etomica.data.IDataSink

putData, putDataInfo

Methods inherited from interface etomica.data.IDataSource

getDataInfo, getTag

Methods inherited from class java.lang.Object

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

Field Detail

maxBlocks

protected int maxBlocks

blockAvgs

protected double[] blockAvgs

currentBlockAvg

protected double currentBlockAvg

totalSumSquare

protected double totalSumSquare

totalBlockVarSum

protected double totalBlockVarSum

totalVarSum

protected double totalVarSum

correlationSum

protected double correlationSum

totalBlockAvg

protected double totalBlockAvg

totalAvg

protected double totalAvg

nominalBlockSize

protected long nominalBlockSize

Constructor Detail

AccumulatorAverageCollapsing

public AccumulatorAverageCollapsing()

Default constructor sets the maximum number of blocks (maxBlocks) to a default value of 20, the initial block size (blockSize) to 1 and the interval for pushing the output data (pushInterval) to 100.

AccumulatorAverageCollapsing

public AccumulatorAverageCollapsing(int maxBlocks)

Constructor with default pushInterval of 100 and initial blockSize of 1.

Parameters:

maxBlocks - the largest number of blocks. Adding new data beyond this triggers collapsing of blocks

AccumulatorAverageCollapsing

public AccumulatorAverageCollapsing(int maxBlocks,
                                    int blockSize)

Constructor with default pushInterval of 100.

Parameters:

maxBlocks - the largest number of blocks. Adding new data beyond this triggers collapsing of blocks

blockSize - the initial number of terms that contribute to each block. Doubles with each collapse of the blocks.

Method Detail

getMaxBlocks

public int getMaxBlocks()

Returns:

the current value of maxBlocks.

setMaxBlocks

public void setMaxBlocks(int newMaxBlocks)

Changes the maximum number of blocks. If the new value is less than the current number of blocks, collapsing is done until number of blocks is less than or equal to the given value.

Parameters:

newMaxBlocks - new value for maxBlocks

Throws:

java.lang.RuntimeException - if newMaxBlocks is less than 4 or an odd number.

processDataInfo

public IDataInfo processDataInfo(IDataInfo incomingDataInfo)

Description copied from class: AccumulatorAverage

Prepares the accumulator for input data. Discards any previous contributions to statistics.

Overrides:

processDataInfo in class AccumulatorAverage

Parameters:

incomingDataInfo - the DataInfo instance for the data that will be given to addData

Returns:

dataInfo object for the output of this accumulator.

addData

public boolean addData(IData data)

Add the given values to the sums and block sums. If any of the given data values is NaN, method returns with no effect on accumulation sums.

Specified by:

addData in class DataAccumulator

Parameters:

data - Data to be added.

Returns:

true if the Accumulator's getData method will now return different data.

doBlockSum

protected void doBlockSum()

Performs the block sum after blockSize calls to addData.

collapseBlocks

protected void collapseBlocks()

getData

public IData getData()

Specified by:

getData in interface IDataSource

Specified by:

getData in class DataAccumulator

Returns:

a DataGroup with Data instances holding the statistics kept by this accumulator (as described in general comments for this class).

reset

public void reset()

Resets all sums to zero. All statistics are cleared.

Overrides:

reset in class AccumulatorAverage

setBlockSize

public void setBlockSize(long newBlockSize)

Sets the size of the block used to group data for error analysis. Resets statistics accumulated so far. Default is 1.

Overrides:

setBlockSize in class AccumulatorAverage

Parameters:

newBlockSize - new block size.