heart.alsvfd.expressions

Class StatisticalExpression

java.lang.Object

heart.alsvfd.expressions.StatisticalExpression

All Implemented Interfaces:

AttributeExpressionInterface, ExpressionInterface

public class StatisticalExpression
extends java.lang.Object
implements AttributeExpressionInterface

Created by sbk on 19.12.14. This class is responsible for implementation of all the statistical operations available in HeaRTDroid. Methods from this class will be later invoked by other components that implements particular operators.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	StatisticalExpression.Builder
static class	StatisticalExpression.StatisticalOperator

Field Summary

Fields

Modifier and Type	Field and Description
protected Attribute	attribute

Constructor Summary

Constructors

Constructor and Description
StatisticalExpression()

Method Summary

Modifier and Type	Method and Description
Value	entropy(java.lang.String attributeName, RelativeTimePeriod period, WorkingMemory wm) Returns entropy of the attribute values from specified period of time.
Value	evaluate(WorkingMemory wm)
Type	evaluateType(WorkingMemory wm) It always returns null, as it cannot be always determined what type is the returned value of.
Attribute	getAttribute()
java.lang.String	getAttributeName()
Value	max(java.lang.String attributeName, RelativeTimePeriod period, WorkingMemory wm) Returns the biggest value of an attribute from specified period of time.
Value	mean(java.lang.String attributeName, RelativeTimePeriod period, WorkingMemory wm) Returns mean of the attribute values from specified period of time.
Value	med(java.lang.String attributeName, RelativeTimePeriod period, WorkingMemory wm) Returns median of the attribute values from specified period of time.
Value	min(java.lang.String attributeName, RelativeTimePeriod period, WorkingMemory wm) Returns the smallest value of an attribute from specified period of time It is applicable only to the numeric attributes.
Value	mode(java.lang.String attributeName, RelativeTimePeriod period, WorkingMemory wm) Returns the most frequent attribute value from specified period of time
Value	stdev(java.lang.String attributeName, RelativeTimePeriod period, WorkingMemory wm) Returns standard deviation of the attribute values from specified period of time.
Value	trend(java.lang.String attributeName, RelativeTimePeriod period, WorkingMemory wm) Returns slope of the trend line fitted to attribute values using the least--squares fit.
Value	var(java.lang.String attributeName, RelativeTimePeriod period, WorkingMemory wm) Returns variance of the attribute values from specified period of time.

Methods inherited from class java.lang.Object

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

Field Detail

attribute

protected Attribute attribute

Constructor Detail

StatisticalExpression

public StatisticalExpression()

Method Detail

getAttributeName

public java.lang.String getAttributeName()

Specified by:

getAttributeName in interface AttributeExpressionInterface

getAttribute

public Attribute getAttribute()

Specified by:

getAttribute in interface AttributeExpressionInterface

max

public Value max(java.lang.String attributeName,
                 RelativeTimePeriod period,
                 WorkingMemory wm)
          throws NotInTheDomainException

Returns the biggest value of an attribute from specified period of time. It is applicable only to the numeric attributes.

Parameters:

attributeName - the attribute name for which the operation has to be performed

period - relative time period from which the values for calculation should be taken.

wm - WorkingMemory object where the historical information about the attribute values are stored

Returns:

maximum over all the values from the given time period

Throws:

NotInTheDomainException

min

public Value min(java.lang.String attributeName,
                 RelativeTimePeriod period,
                 WorkingMemory wm)
          throws NotInTheDomainException

Returns the smallest value of an attribute from specified period of time It is applicable only to the numeric attributes.

Parameters:

attributeName - the attribute name for which the operation has to be performed

period - relative time period from which the values for calculation should be taken.

wm - WorkingMemory object where the historical information about the attribute values are stored

Returns:

maximum over all the values from the given time period

Throws:

NotInTheDomainException

med

public Value med(java.lang.String attributeName,
                 RelativeTimePeriod period,
                 WorkingMemory wm)
          throws NotInTheDomainException

Returns median of the attribute values from specified period of time. It is applicable only to the numeric attributes.

Parameters:

attributeName - the attribute name for which the operation has to be performed

period - relative time period from which the values for calculation should be taken.

wm - WorkingMemory object where the historical information about the attribute values are stored

Returns:

median over the values from the given time period

Throws:

NotInTheDomainException

stdev

public Value stdev(java.lang.String attributeName,
                   RelativeTimePeriod period,
                   WorkingMemory wm)
            throws NotInTheDomainException

Returns standard deviation of the attribute values from specified period of time.

Parameters:

attributeName - the attribute name for which the operation has to be performed

period - relative time period from which the values for calculation should be taken.

wm - WorkingMemory object where the historical information about the attribute values are stored

Returns:

the standard deviation over the values from the given time period

Throws:

NotInTheDomainException

trend

public Value trend(java.lang.String attributeName,
                   RelativeTimePeriod period,
                   WorkingMemory wm)

Returns slope of the trend line fitted to attribute values using the least--squares fit. It is applicable only to the numeric attributes.

Parameters:

attributeName - the attribute name for which the operation has to be performed

period - relative time period from which the values for calculation should be taken.

wm - WorkingMemory object where the historical information about the attribute values are stored

Returns:

trend over the values from the given time period

Throws:

NotInTheDomainException

var

public Value var(java.lang.String attributeName,
                 RelativeTimePeriod period,
                 WorkingMemory wm)
          throws NotInTheDomainException

Returns variance of the attribute values from specified period of time. It is applicable only to the numeric attributes.

Parameters:

attributeName - the attribute name for which the operation has to be performed

period - relative time period from which the values for calculation should be taken.

wm - WorkingMemory object where the historical information about the attribute values are stored

Returns:

variance over the values from the given time period

Throws:

NotInTheDomainException

entropy

public Value entropy(java.lang.String attributeName,
                     RelativeTimePeriod period,
                     WorkingMemory wm)
              throws NotInTheDomainException

Returns entropy of the attribute values from specified period of time. It is applicable only to the simple attributes.

Parameters:

attributeName - the attribute name for which the operation has to be performed

period - relative time period from which the values for calculation should be taken.

wm - WorkingMemory object where the historical information about the attribute values are stored

Returns:

entropy of the values from the given time period

Throws:

NotInTheDomainException

mode

public Value mode(java.lang.String attributeName,
                  RelativeTimePeriod period,
                  WorkingMemory wm)

Returns the most frequent attribute value from specified period of time

Parameters:

attributeName - the attribute name for which the operation has to be performed

period - relative time period from which the values for calculation should be taken.

wm - WorkingMemory object where the historical information about the attribute values are stored

Returns:

the mode over the values from the given time period

Throws:

NotInTheDomainException

mean

public Value mean(java.lang.String attributeName,
                  RelativeTimePeriod period,
                  WorkingMemory wm)
           throws NotInTheDomainException

Returns mean of the attribute values from specified period of time. It is applicable only to the numeric attributes.

Parameters:

attributeName - the attribute name for which the operation has to be performed

period - relative time period from which the values for calculation should be taken.

wm - WorkingMemory object where the historical information about the attribute values are stored

Returns:

the mean over the values from the given time period

Throws:

NotInTheDomainException

evaluate

public Value evaluate(WorkingMemory wm)
               throws java.lang.UnsupportedOperationException,
                      NotInTheDomainException

Specified by:

evaluate in interface ExpressionInterface

Throws:

java.lang.UnsupportedOperationException

NotInTheDomainException

evaluateType

public Type evaluateType(WorkingMemory wm)

It always returns null, as it cannot be always determined what type is the returned value of.

Specified by:

evaluateType in interface ExpressionInterface

Parameters:

wm - The WorkingMemory object with respect to which a type of an expression should be evaluated

Returns:

type of the expression