org.protempa.backend.asb.java

Class TrendAlgorithm

java.lang.Object

org.protempa.AbstractAlgorithm

org.protempa.backend.asb.java.TrendAlgorithm

All Implemented Interfaces:

Serializable, Algorithm

public final class TrendAlgorithm
extends AbstractAlgorithm

Detects whether the slope of a linear regression line drawn through the values of a time sequence segment is above and/or below a specified value. We do a variability check so as not to detect slope thresholds in wildly varying data. It handles missing (null) values (see compute(org.protempa.proposition.Segment<org.protempa.proposition.PrimitiveParameter>, org.protempa.AlgorithmArguments) below), but does not handle nan yet.

Author:

Andrew Post

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
TrendAlgorithm(Algorithms algorithms, String id)

Method Summary

Modifier and Type	Method and Description
Value	compute(Segment<PrimitiveParameter> segment, AlgorithmArguments args) Computes whether the slope of a linear regression line drawn through the values of a time sequence segment is above and/or below a specified value.

Methods inherited from class org.protempa.AbstractAlgorithm

close, createDataSourceConstraint, finalize, getAdvanceRowSkipEnd, getId, getInValueType, getMaximumNumberOfValues, getMinimumNumberOfValues, getParameters, initialize, parameter, setAdvanceRowSkipEnd, setInValueType, setMaximumNumberOfValues, setMinimumNumberOfValues, setParameters, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

TrendAlgorithm

public TrendAlgorithm(Algorithms algorithms,
                      String id)

Method Detail

compute

public Value compute(Segment<PrimitiveParameter> segment,
                     AlgorithmArguments args)

Computes whether the slope of a linear regression line drawn through the values of a time sequence segment is above and/or below a specified value.

Specified by:

compute in interface Algorithm

Specified by:

compute in class AbstractAlgorithm

Parameters:

segment - a Segment object.

Returns:

a Value if the slope of the segment is above and/or below the specified thresholds, null otherwise. If any of the values of segment are null, this methods also returns null.

See Also:

org.protempa.AbstractAlgorithm#compute(org.protempa.proposition.Segment)