Package de.uka.ipd.sdq.probfunction.math.impl

Class BoxedPDFImpl

java.lang.Object

de.uka.ipd.sdq.probfunction.math.impl.ProbabilityFunctionImpl

de.uka.ipd.sdq.probfunction.math.impl.ProbabilityDensityFunctionImpl

de.uka.ipd.sdq.probfunction.math.impl.BoxedPDFImpl

All Implemented Interfaces:

IBoxedPDF, IProbabilityDensityFunction, IProbabilityFunction

public class BoxedPDFImpl
extends ProbabilityDensityFunctionImpl
implements IBoxedPDF

Nested Class Summary

Nested classes/interfaces inherited from class de.uka.ipd.sdq.probfunction.math.impl.ProbabilityDensityFunctionImpl

ProbabilityDensityFunctionImpl.CompareOperation

Field Summary

Fields inherited from class de.uka.ipd.sdq.probfunction.math.impl.ProbabilityFunctionImpl

pfFactory, randomGenerator

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	BoxedPDFImpl(IUnit unit, IRandomGenerator generator)

Method Summary

Modifier and Type	Method	Description
IProbabilityDensityFunction	add(IProbabilityDensityFunction pdf)	Adds two ProbabilityDensityFunctions on a "per value" basis: h(x) = f(x) + g(x) An addition can only be performed if both functions are in the same domain (frequency or time).
void	checkConstrains()	checks whether the following constraints are fulfilled : the sum of all probabilities is one.
IProbabilityDensityFunction	div(IProbabilityDensityFunction pdf)	Divides two ProbabilityDensityFunctions on a "per value" basis: h(x) = f(x) / g(x) A division can only be performed if both functions are in the same domain (frequency or time).
double	drawSample()	Generates a random number of the probability function's domain, whose distribution is defined by the probability function.
boolean	equals(Object obj)
double	getArithmeticMeanValue()	Get the mean value of the BoxedPDF
IProbabilityDensityFunction	getCumulativeFunction()	returns the cumulative probability function associated with this probability function.
IProbabilityDensityFunction	getFourierTransform()	Computes the fourier transform of the probability density function.
IProbabilityDensityFunction	getInverseFourierTransform()	Computes the inverse fourier transform of the probability density function.
double	getLowerDomainBorder()	Returns the smallest values of the domain.
Object	getMedian()	A median is a number dividing the higher half of a sample, a population, or a probability distribution from the lower half.
Object	getPercentile(int p)	In descriptive statistics, the 'p'th percentile is a scale value for a data series equal to the p/100 quantile.
List<Double>	getProbabilities()
double	getProbabilitySum()	Computes the sum of all probabilities specified in the function.
List<IContinuousSample>	getSamples()	Ordered list of ContinuousSamples, which define the sequence of boxes.
List<Double>	getValues()
double	greaterThan(IProbabilityDensityFunction pdf)	Computes the probability that the random variable specified by this PDF is greater than the random variable specified by pdf.
boolean	isInFrequencyDomain()	True, if the probability density function is in the frequency domain (frequency domain graph shows how much of the signal lies within each given frequency band over a range of frequencies).
boolean	isInTimeDomain()	True, if the probability density function is the time domain (a time domain graph shows how a signal changes over time).
double	lessThan(IProbabilityDensityFunction pdf)	Computes the probability that the random variable specified by this PDF is less than the random variable specified by pdf.
IProbabilityDensityFunction	mult(IProbabilityDensityFunction pdf)	Multiplies two ProbabilityDensityFunctions on a "per value" basis: h(x) = f(x) * g(x) A multiplication can only be performed if both functions are in the same domain (frequency or time).
double	probabilisticEquals(IProbabilityDensityFunction pdf)	Computes the probability that two random variables characterised by the given PDFs are equal.
IProbabilityDensityFunction	scale(double scalar)	Scales a ProbabilityDensityFunctions on a "per value" basis: h(x) = a * f(x)
void	setSamples(List<IContinuousSample> samples)
IProbabilityDensityFunction	shiftDomain(double scalar)	Shifts the domain values of the PDF by the given scalar
IProbabilityDensityFunction	stretchDomain(double scalar)	Stretches the domain values of the PDF.
IProbabilityDensityFunction	sub(IProbabilityDensityFunction pdf)	Subtracts two ProbabilityDensityFunctions on a "per value" basis: h(x) = f(x) - g(x) A substraction can only be performed if both functions are in the same domain (frequency or time).
String	toString()

Methods inherited from class de.uka.ipd.sdq.probfunction.math.impl.ProbabilityFunctionImpl

getRandomGenerator, getUnit, hasOrderedDomain, setInFrequencyDomain, setRandomGenerator, setUnit

Methods inherited from class java.lang.Object

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

Methods inherited from interface de.uka.ipd.sdq.probfunction.math.IProbabilityFunction

getUnit, hasOrderedDomain

Constructor Details

BoxedPDFImpl

protected BoxedPDFImpl(IUnit unit,
 IRandomGenerator generator)

Method Details

add

public IProbabilityDensityFunction add(IProbabilityDensityFunction pdf)
                                throws FunctionsInDifferenDomainsException,
UnknownPDFTypeException,
IncompatibleUnitsException

Description copied from interface: IProbabilityDensityFunction

Adds two ProbabilityDensityFunctions on a "per value" basis:
h(x) = f(x) + g(x)
An addition can only be performed if both functions are in the same domain (frequency or time). If not a FunctionsInDifferenDomainsException is thrown.

Specified by:

add in interface IProbabilityDensityFunction

Parameters:

pdf - g(x), probability density function to add.

Returns:

The sum of this function (f(x)) and pdf (g(x))

Throws:

FunctionsInDifferenDomainsException - Thrown if both functions are in different domains.

UnknownPDFTypeException - Thrown if one of the function is of an unknown type (not SamplePDf or BoxedPDF).

IncompatibleUnitsException - Thrown if both functions have units that do not match.

mult

public IProbabilityDensityFunction mult(IProbabilityDensityFunction pdf)
                                 throws FunctionsInDifferenDomainsException,
UnknownPDFTypeException,
IncompatibleUnitsException

Description copied from interface: IProbabilityDensityFunction

Multiplies two ProbabilityDensityFunctions on a "per value" basis:
h(x) = f(x) * g(x)
A multiplication can only be performed if both functions are in the same domain (frequency or time). If not a FunctionsInDifferenDomainsException is thrown.

Specified by:

mult in interface IProbabilityDensityFunction

Parameters:

pdf - g(x), probability density function to multiply with.

Returns:

The product of this function (f(x)) and pdf (g(x))

Throws:

FunctionsInDifferenDomainsException - Thrown if both functions are in different domains.

UnknownPDFTypeException - Thrown if one of the function is of an unknown type (not SamplePDf or BoxedPDF).

IncompatibleUnitsException - Thrown if both functions have units that do not match.

scale

public IProbabilityDensityFunction scale(double scalar)

Description copied from interface: IProbabilityDensityFunction

Scales a ProbabilityDensityFunctions on a "per value" basis:
h(x) = a * f(x)

Specified by:

scale in interface IProbabilityDensityFunction

Parameters:

scalar - a, value to scale with.

Returns:

The scaled function a*f(x)

getSamples

public List<IContinuousSample> getSamples()

Description copied from interface: IBoxedPDF

Ordered list of ContinuousSamples, which define the sequence of boxes.

Specified by:

getSamples in interface IBoxedPDF

Returns:

ContinuousSamples approximating the probability density function.

getValues

public List<Double> getValues()

getProbabilities

public List<Double> getProbabilities()

setSamples

public void setSamples(List<IContinuousSample> samples)
                throws DoubleSampleException

Throws:

DoubleSampleException

div

public IProbabilityDensityFunction div(IProbabilityDensityFunction pdf)
                                throws FunctionsInDifferenDomainsException,
UnknownPDFTypeException,
IncompatibleUnitsException

Description copied from interface: IProbabilityDensityFunction

Divides two ProbabilityDensityFunctions on a "per value" basis:
h(x) = f(x) / g(x)
A division can only be performed if both functions are in the same domain (frequency or time). If not a FunctionsInDifferenDomainsException is thrown.

Specified by:

div in interface IProbabilityDensityFunction

Parameters:

pdf - g(x), probability density function to divide by.

Returns:

The fraction of this function (f(x)) and pdf (g(x))

Throws:

FunctionsInDifferenDomainsException

UnknownPDFTypeException

IncompatibleUnitsException

drawSample

public double drawSample()

Description copied from interface: IProbabilityDensityFunction

Generates a random number of the probability function's domain, whose distribution is defined by the probability function.

Specified by:

drawSample in interface IProbabilityDensityFunction

Returns:

A sample of the PDF's domain.

getFourierTransform

public IProbabilityDensityFunction getFourierTransform()
                                                throws FunctionNotInTimeDomainException

Description copied from interface: IProbabilityDensityFunction

Computes the fourier transform of the probability density function. Can only be applied if 'isInTimeDomain()' is true, otherwise a FunctionNotInTimeDomain exception is thrown.

Specified by:

getFourierTransform in interface IProbabilityDensityFunction

Returns:

fourier transform of the PDF (in frequency domain)

Throws:

FunctionNotInTimeDomainException

getInverseFourierTransform

public IProbabilityDensityFunction getInverseFourierTransform()
                                                       throws FunctionNotInFrequencyDomainException

Description copied from interface: IProbabilityDensityFunction

Computes the inverse fourier transform of the probability density function. Can only be applied if 'isInFrequencyDomain()' is true, otherwise a FunctionNotInFrequencyDomainException is thrown.

Specified by:

getInverseFourierTransform in interface IProbabilityDensityFunction

Returns:

inverse fourier transform of the PDF (in time domain)

Throws:

FunctionNotInFrequencyDomainException

getLowerDomainBorder

public double getLowerDomainBorder()

Description copied from interface: IProbabilityDensityFunction

Returns the smallest values of the domain. At the moment this will be zero. However, future implementations might allow arbitrary values here.

Specified by:

getLowerDomainBorder in interface IProbabilityDensityFunction

Returns:

Smallest value of the domain.

sub

public IProbabilityDensityFunction sub(IProbabilityDensityFunction pdf)
                                throws FunctionsInDifferenDomainsException,
UnknownPDFTypeException,
IncompatibleUnitsException

Description copied from interface: IProbabilityDensityFunction

Subtracts two ProbabilityDensityFunctions on a "per value" basis:
h(x) = f(x) - g(x)
A substraction can only be performed if both functions are in the same domain (frequency or time). If not a FunctionsInDifferenDomainsException is thrown.

Specified by:

sub in interface IProbabilityDensityFunction

Parameters:

pdf - g(x), probability density function to substract.

Returns:

The difference of this function (f(x)) and pdf (g(x))

Throws:

FunctionsInDifferenDomainsException - Thrown if both functions are in different domains.

UnknownPDFTypeException - Thrown if one of the function is of an unknown type (not SamplePDf or BoxedPDF).

IncompatibleUnitsException - Thrown if both functions have units that do not match.

getArithmeticMeanValue

public double getArithmeticMeanValue()
                              throws DomainNotNumbersException

Get the mean value of the BoxedPDF

Specified by:

getArithmeticMeanValue in interface IProbabilityFunction

Parameters:

list -

Returns:

the mean value

Throws:

DomainNotNumbersException

getMedian

public Object getMedian()
                 throws UnorderedDomainException

Description copied from interface: IProbabilityFunction

A median is a number dividing the higher half of a sample, a population, or a probability distribution from the lower half. The median of a finite list of numbers can be found by arranging all the observations from lowest value to highest value and picking the middle one.

Specified by:

getMedian in interface IProbabilityFunction

Returns:

Object that is the border for the median.

Throws:

UnorderedDomainException

getPercentile

public Object getPercentile(int p)
                     throws IndexOutOfBoundsException,
UnorderedDomainException

Description copied from interface: IProbabilityFunction

In descriptive statistics, the 'p'th percentile is a scale value for a data series equal to the p/100 quantile. Thus:
* The 1st percentile cuts off lowest 1% of data
* The 98th percentile cuts off lowest 98% of data
* The 25th percentile is the first quartile
* The 50th percentile is the median.
One definition is that the pth percentile of n ordered values is obtained by first calculating the rank k = p(n+1)/100, rounded to the nearest integer and then taking the value that corresponds to that rank.

Specified by:

getPercentile in interface IProbabilityFunction

Parameters:

p - sets the percentile which shall be computed. p must take values between 0 and 100.

Returns:

Object that is the border for the 'p'th percentile.

Throws:

IndexOutOfBoundsException

UnorderedDomainException

isInFrequencyDomain

public boolean isInFrequencyDomain()

Description copied from interface: IProbabilityFunction

True, if the probability density function is in the frequency domain (frequency domain graph shows how much of the signal lies within each given frequency band over a range of frequencies). This means it is the result of a Fourier transformation.

Specified by:

isInFrequencyDomain in interface IProbabilityFunction

Overrides:

isInFrequencyDomain in class ProbabilityFunctionImpl

Returns:

True, if in frequency domain, false otherwise.

isInTimeDomain

public boolean isInTimeDomain()

Description copied from interface: IProbabilityFunction

True, if the probability density function is the time domain (a time domain graph shows how a signal changes over time). This means that it is not a result of a Fourier transform.

Specified by:

isInTimeDomain in interface IProbabilityFunction

Overrides:

isInTimeDomain in class ProbabilityFunctionImpl

Returns:

True, if in time domain; false otherwise.

getProbabilitySum

public double getProbabilitySum()

Description copied from interface: IProbabilityFunction

Computes the sum of all probabilities specified in the function. For pdfs this is the area under the graph; for pmfs the sum of all probabilities.

Specified by:

getProbabilitySum in interface IProbabilityFunction

Returns:

Sum of all probabilities in the function.

checkConstrains

public void checkConstrains()
                     throws InvalidSampleValueException,
UnitNameNotSetException,
UnitNotSetException,
ProbabilitySumNotOneException

Description copied from interface: IProbabilityFunction

checks whether the following constraints are fulfilled : the sum of all probabilities is one. all values are greater or equal 0.

Specified by:

checkConstrains in interface IProbabilityFunction

Throws:

InvalidSampleValueException

UnitNameNotSetException

UnitNotSetException

ProbabilitySumNotOneException

getCumulativeFunction

public IProbabilityDensityFunction getCumulativeFunction()

Description copied from interface: IProbabilityDensityFunction

returns the cumulative probability function associated with this probability function.

Specified by:

getCumulativeFunction in interface IProbabilityDensityFunction

Returns:

the computed cumulative probability function.

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

probabilisticEquals

public double probabilisticEquals(IProbabilityDensityFunction pdf)

Description copied from interface: IProbabilityDensityFunction

Computes the probability that two random variables characterised by the given PDFs are equal. Note that the randomvariables have to be independent.

Specified by:

probabilisticEquals in interface IProbabilityDensityFunction

Parameters:

pdf - PDF to compare to.

Returns:

Probability that the two random variables characterised by the PDFs are equal.

greaterThan

public double greaterThan(IProbabilityDensityFunction pdf)

Description copied from interface: IProbabilityDensityFunction

Computes the probability that the random variable specified by this PDF is greater than the random variable specified by pdf. Note that the randomvariables have to be independent.

Specified by:

greaterThan in interface IProbabilityDensityFunction

Parameters:

pdf - PDF to compare to.

Returns:

Probability X_this > X_pdf

lessThan

public double lessThan(IProbabilityDensityFunction pdf)

Description copied from interface: IProbabilityDensityFunction

Computes the probability that the random variable specified by this PDF is less than the random variable specified by pdf. Note that the randomvariables have to be independent.

Specified by:

lessThan in interface IProbabilityDensityFunction

Parameters:

pdf - PDF to compare to.

Returns:

Probability X_this < X_pdf

stretchDomain

public IProbabilityDensityFunction stretchDomain(double scalar)

Stretches the domain values of the PDF. This is equivalent to the multiplication of the specified random variable by the given scalar. Scalar must not be 0. If it is 0, a RuntimeException is thrown.

Specified by:

stretchDomain in interface IProbabilityDensityFunction

Parameters:

scalar - must not be 0

Returns:

shiftDomain

public IProbabilityDensityFunction shiftDomain(double scalar)
                                        throws DomainNotNumbersException

Shifts the domain values of the PDF by the given scalar Returns itself if scalar == 0.

Specified by:

shiftDomain in interface IProbabilityDensityFunction

Returns:

Throws:

DomainNotNumbersException

toString

public String toString()

Overrides:

toString in class Object