org.modeshape.common.statistic

Class Histogram<T extends Number>

java.lang.Object

org.modeshape.common.statistic.Histogram<T>

Type Parameters:

T - the type of value

@NotThreadSafe
public class Histogram<T extends Number>
extends Object

A representation of a histogram of values.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	Histogram.Bucket Represents a bucket in a histogram.
class	Histogram.BucketingStrategy
class	Histogram.DefaultBucketingStrategy
class	Histogram.ExplicitBucketingStrategy
class	Histogram.StandardDeviationBucketingStrategy

Field Summary

Fields

Modifier and Type	Field and Description
static int	DEFAULT_BUCKET_COUNT
static int	DEFAULT_SIGNIFICANT_FIGURES
protected MathOperations<T>	math
protected List<T>	values

Constructor Summary

Constructors

Constructor and Description
Histogram(MathOperations<T> operations, List<T> values)
Histogram(MathOperations<T> operations, T... values)

Method Summary

Modifier and Type	Method and Description
protected void	compute()
protected static <T> List<T>	getBucketBoundaries(MathOperations<T> math, T lowerBound, T upperBound, T actualMinimum, T actualMaximum, int bucketCount, int bucketWidthSigFigs)
int	getBucketCount() Return the number of buckets in this histogram.
List<Histogram.Bucket>	getBuckets() Get the buckets in this histogram.
MathOperations<T>	getMathOperations()
protected long	getMaximumCount()
protected float	getMaximumPercentage()
int	getSignificantFigures()
Histogram.BucketingStrategy	getStrategy()
List<String>	getTextGraph(int maxBarLength) Generate a textual (horizontal) bar graph of this histogram.
long	getTotalNumberOfValues() Return the total number of values that have gone into this histogram.
Histogram<T>	setBucketCount(int count) Set the number of buckets that this histogram will use.
Histogram<T>	setSignificantFigures(int significantFigures) Set the number of significant figures used in the calculation of the bucket widths.
void	setStrategy(double median, double standardDeviation, int sigma) Set the histogram to use the standard deviation to determine the bucket sizes.
void	setStrategy(T minimum, T maximum) Set the histogram to use the supplied minimum and maximum values to determine the bucket size.
void	setStrategyToDefault() Set the histogram to use the actual minimum and maximum values to determine the bucket sizes.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_BUCKET_COUNT

public static final int DEFAULT_BUCKET_COUNT

See Also:

Constant Field Values

DEFAULT_SIGNIFICANT_FIGURES

public static final int DEFAULT_SIGNIFICANT_FIGURES

See Also:

Constant Field Values

math

protected final MathOperations<T extends Number> math

values

protected final List<T extends Number> values

Constructor Detail

Histogram

public Histogram(MathOperations<T> operations,
                 List<T> values)

Histogram

@SafeVarargs
public Histogram(MathOperations<T> operations,
                               T... values)

Method Detail

getStrategy

public Histogram.BucketingStrategy getStrategy()

getMathOperations

public MathOperations<T> getMathOperations()

setStrategy

public void setStrategy(double median,
                        double standardDeviation,
                        int sigma)

Set the histogram to use the standard deviation to determine the bucket sizes.

Parameters:

median -

standardDeviation -

sigma -

setStrategy

public void setStrategy(T minimum,
                        T maximum)

Set the histogram to use the supplied minimum and maximum values to determine the bucket size.

Parameters:

minimum -

maximum -

setStrategyToDefault

public void setStrategyToDefault()

Set the histogram to use the actual minimum and maximum values to determine the bucket sizes.

getSignificantFigures

public int getSignificantFigures()

setSignificantFigures

public Histogram<T> setSignificantFigures(int significantFigures)

Set the number of significant figures used in the calculation of the bucket widths.

Parameters:

significantFigures - the number of significant figures for the bucket widths

Returns:

this histogram, useful for method-chaining

See Also:

DEFAULT_SIGNIFICANT_FIGURES

getBucketCount

public int getBucketCount()

Return the number of buckets in this histogram.

Returns:

the number of buckets.

setBucketCount

public Histogram<T> setBucketCount(int count)

Set the number of buckets that this histogram will use.

Parameters:

count - the number of buckets

Returns:

this histogram, useful for method-chaining

See Also:

DEFAULT_BUCKET_COUNT

getBuckets

public List<Histogram.Bucket> getBuckets()

Get the buckets in this histogram. If the histogram has not yet been computed, this method will cause it to be generated. The resulting list should not be modified.

Returns:

the histogram buckets.

compute

protected void compute()

getTotalNumberOfValues

public long getTotalNumberOfValues()

Return the total number of values that have gone into this histogram.

Returns:

the total number of values

See Also:

Histogram.Bucket.getPercentageOfValues()

getMaximumPercentage

protected float getMaximumPercentage()

getMaximumCount

protected long getMaximumCount()

getTextGraph

public List<String> getTextGraph(int maxBarLength)

Generate a textual (horizontal) bar graph of this histogram.

Parameters:

maxBarLength - the maximum bar length, or 0 if the bar length is to represent actual counts

Returns:

the strings that make up the histogram

getBucketBoundaries

protected static <T> List<T> getBucketBoundaries(MathOperations<T> math,
                                                 T lowerBound,
                                                 T upperBound,
                                                 T actualMinimum,
                                                 T actualMaximum,
                                                 int bucketCount,
                                                 int bucketWidthSigFigs)