org.ai_heuristic.functs

Class FunctionMetric

java.lang.Object

org.ai_heuristic.functs.Function

org.ai_heuristic.functs.FunctionMetric

All Implemented Interfaces:

FunctionDef, FunctionMetricDef

Direct Known Subclasses:

CityBlockDistance, CosineSimilarity, DemerauLevenshtein, EuclideanDistance, Hamming, IndexSimilarity, JaccardCoefficient, JaroWinkler, KullbackLeibler, Levenshtein, MinkowskiDistance, NGram

public abstract class FunctionMetric
extends Function
implements FunctionMetricDef

This is the base class for any of the evaluation metrics or functions that compare two datasets and use the MetricCompare objects only.

Author:

Kieran Greer

Field Summary

Fields inherited from class org.ai_heuristic.functs.Function

config, mathCompare, valueType

Constructor Summary

Constructors

Constructor and Description
FunctionMetric() Create a new instance of FunctionMetric.
FunctionMetric(java.lang.String thisValueType) Create a new instance of FunctionMetric.
FunctionMetric(java.lang.String thisValueType, java.util.HashMap<java.lang.String,?> thisConfig) Create a new instance of FunctionMetric.

Method Summary

Modifier and Type	Method and Description
abstract ReplySet	evaluate(MetricDataset ds1, MetricDataset ds2) Evaluate the comparison between the two datasets and return the result.
protected ReplySet	evaluateCompare(MetricCompare dataset) Return a value based on the function evaluation.
abstract boolean	isBetter(java.lang.String valueType, java.lang.Object value1, java.lang.Object value2) Return true if value2 is better than value1, as determined by the measurements of this evaluation function.
boolean	lib() Return true if a larger distance between the two vectors is better.
abstract FunctionMetric	newInstance() Create and return a new instance of the function, initialised with this function's value type valueType and math evaluator eval.
abstract boolean	sib() Return true if a smaller distance between the two vectors is better.

Methods inherited from class org.ai_heuristic.functs.Function

checkValueType, createFunction, createFunction, createFunction, evaluate, getConfigParams, initialise, innerObject, isLegalNumber, setConfigParams, setEvaluator, setValueType

Methods inherited from class java.lang.Object

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

Constructor Detail

FunctionMetric

public FunctionMetric()
               throws java.lang.Exception

Create a new instance of FunctionMetric.

Throws:

java.lang.Exception - any error.

FunctionMetric

public FunctionMetric(java.lang.String thisValueType)
               throws java.lang.Exception

Create a new instance of FunctionMetric. The eval evaluator is set to SimpleMathCompare. To change this, use the setEvaluator method.

Parameters:

thisValueType - the type of object being evaluated. Can be null if set later or not used.

Throws:

java.lang.Exception - any error.

FunctionMetric

public FunctionMetric(java.lang.String thisValueType,
                      java.util.HashMap<java.lang.String,?> thisConfig)
               throws java.lang.Exception

Create a new instance of FunctionMetric. The eval evaluator is set to SimpleMathCompare. To change this, use the setEvaluator method.

Parameters:

thisValueType - the type of object being evaluated. Can be null if set later or not used.

thisConfig - list of initialisation function-specific parameters.

Throws:

java.lang.Exception - any error.

Method Detail

isBetter

public abstract boolean isBetter(java.lang.String valueType,
                                 java.lang.Object value1,
                                 java.lang.Object value2)
                          throws java.lang.Exception

Return true if value2 is better than value1, as determined by the measurements of this evaluation function.

Parameters:

valueType - the java type of the values to be evaluated.

value1 - the first value type.

value2 - the second value type.

Returns:

true if value2 is better than value1, as determined by this evaluation function.

Throws:

java.lang.Exception - any error.

sib

public abstract boolean sib()

Return true if a smaller distance between the two vectors is better.

Returns:

true if a smaller evaluation is better.

lib

public boolean lib()

Return true if a larger distance between the two vectors is better.

Returns:

true if a larger evaluation is better. Returns opposite of sib().

newInstance

public abstract FunctionMetric newInstance()
                                    throws java.lang.Exception

Create and return a new instance of the function, initialised with this function's value type valueType and math evaluator eval.

Returns:

a new instance of this function.

Throws:

java.lang.Exception - any error.

evaluateCompare

protected ReplySet evaluateCompare(MetricCompare dataset)
                            throws java.lang.Exception

Return a value based on the function evaluation.

Parameters:

dataset - the value to pass through the function. This must be of type MetricCompare, for comparing two different value sets. The individual components of the MetricCompare object are then passed to the evaluate function which would be expected to return a floating point evaluation.

Returns:

the processed value, or null if the wrong value type in passed in.

Throws:

java.lang.Exception - any error.

evaluate

public abstract ReplySet evaluate(MetricDataset ds1,
                                  MetricDataset ds2)
                           throws java.lang.Exception

Evaluate the comparison between the two datasets and return the result. If each list has only one object, then apply to the objects directly and not the lists.

Specified by:

evaluate in interface FunctionMetricDef

Parameters:

ds1 - first dataset.

ds2 - second dataset.

Returns:

the result of applying the operator to the values, wrapped in a ReplySet object.

Throws:

java.lang.Exception - any error.