org.android.activityminer.logic.features.calculators
Class FFTCalculator<T extends Enum<T> & Dimensions>

java.lang.Object
  org.android.activityminer.logic.features.calculators.AbstractCalculator<T,U>
      org.android.activityminer.logic.features.calculators.AbstractCompositeCalculator<T,Double>
          org.android.activityminer.logic.features.calculators.FFTCalculator<T>

Type Parameters:

T - the enumeration type for the dimensions

All Implemented Interfaces:

ObservableEventSource<FFTCalculatorEvent>, ObserverRegistration<FFTCalculatorEvent>, Calculator<Double>, CompositeCalculator<Double>

public final class FFTCalculator<T extends Enum<T> & Dimensions>
extends AbstractCompositeCalculator<T,Double>
implements ObservableEventSource<FFTCalculatorEvent>

Implementation of an observable FFT component calculator. It can be observed for all but the DC component which is returned as calculator value. Energy spectrum is calculated as the squared magnitudes of the FFT coefficients: for the FFT coefficient FFT(i)=(re, im) the magnitude is mag(i)=Math.sqrt(re*re + im*im) and the spectral energy is se(i)=(mag(i)*mag(i)).

Field Summary

private int	cntComponents The count of FFT components.
private ObservableEventSource<FFTCalculatorEvent>	fftEventSource The event source to delegate to.
private DimensionValueCache<T>	valueCache The value cache.

Fields inherited from class org.android.activityminer.logic.features.calculators.AbstractCalculator

dimension, value

Constructor Summary

FFTCalculator(DimensionValueCache<T> valueCache)
Constructor

Method Summary

int	getComponentCount() Getter for the component count
Double	getCompositeValue() Does calculate the composite value.
Double	getInitialValue() Method for value initialization.
DimensionValueCache<T>	getValueCache() Getter for the value cache calculator.
boolean	hasObservers()
void	notify(FFTCalculatorEvent data)
void	registerEventObserver(EventObserver<? extends FFTCalculatorEvent> observer)
void	removeAllObservers()
void	unregisterEventObserver(EventObserver<? extends FFTCalculatorEvent> observer)

Methods inherited from class org.android.activityminer.logic.features.calculators.AbstractCompositeCalculator

getValue, reset

Methods inherited from class org.android.activityminer.logic.features.calculators.AbstractCalculator

getDimension

Methods inherited from class java.lang.Object

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

Field Detail

cntComponents

private int cntComponents

The count of FFT components.

fftEventSource

private final ObservableEventSource<FFTCalculatorEvent> fftEventSource

The event source to delegate to.

valueCache

private final DimensionValueCache<T extends Enum<T> & Dimensions> valueCache

The value cache.

Constructor Detail

FFTCalculator

public FFTCalculator(DimensionValueCache<T> valueCache)

Constructor

Parameters:

valueCache - the value cache

Method Detail

getComponentCount

public final int getComponentCount()

Getter for the component count

Returns:

the component count

getInitialValue

public final Double getInitialValue()

Description copied from interface: Calculator

Method for value initialization.

Specified by:

getInitialValue in interface Calculator<Double>

Returns:

the initialized value

getCompositeValue

public Double getCompositeValue()

Description copied from interface: CompositeCalculator

Does calculate the composite value.

Specified by:

getCompositeValue in interface CompositeCalculator<Double>

Returns:

the composite value

getValueCache

public DimensionValueCache<T> getValueCache()

Getter for the value cache calculator.

Returns:

the value cache

registerEventObserver

public void registerEventObserver(EventObserver<? extends FFTCalculatorEvent> observer)

Specified by:

registerEventObserver in interface ObserverRegistration<FFTCalculatorEvent>

unregisterEventObserver

public void unregisterEventObserver(EventObserver<? extends FFTCalculatorEvent> observer)

Specified by:

unregisterEventObserver in interface ObserverRegistration<FFTCalculatorEvent>

removeAllObservers

public void removeAllObservers()

Specified by:

removeAllObservers in interface ObserverRegistration<FFTCalculatorEvent>

notify

public void notify(FFTCalculatorEvent data)

Specified by:

notify in interface ObservableEventSource<FFTCalculatorEvent>

hasObservers

public boolean hasObservers()

Specified by:

hasObservers in interface ObservableEventSource<FFTCalculatorEvent>