weka.core.pmml
Class Expression

java.lang.Object
  weka.core.pmml.Expression

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

Constant, Discretize, FieldRef, NormContinuous, NormDiscrete

public abstract class Expression
extends Object
implements Serializable

See Also:

Serialized Form

Constructor Summary

Expression(FieldMetaInfo.Optype opType, ArrayList<Attribute> fieldDefs)

Method Summary

static Expression	getExpression(Node container, FieldMetaInfo.Optype opType, ArrayList<Attribute> fieldDefs, weka.core.pmml.TransformationDictionary transDict) Static factory method that returns a subclass of Expression that encapsulates the type of expression contained in the Element supplied.
static Expression	getExpression(String name, Node expression, FieldMetaInfo.Optype opType, ArrayList<Attribute> fieldDefs, weka.core.pmml.TransformationDictionary transDict) Static factory method that returns a subclass of Expression that encapsulates the type of expression supplied as an argument.
Attribute	getFieldDef(String attName) Return the named attribute from the list of reference fields.
int	getFieldDefIndex(String attName)
FieldMetaInfo.Optype	getOptype() Get the optype of the result of applying this Expression.
abstract double	getResult(double[] incoming) Get the result of evaluating the expression.
abstract String	getResultCategorical(double[] incoming) Gets the result of evaluating the expression when the optype is categorical or ordinal as the actual String value.
double	getResultContinuous(double[] incoming) Get the result of evaluating the expression for continuous optype.
void	setFieldDefs(ArrayList<Attribute> fieldDefs) Set the field definitions for this Expression to use
String	toString()
String	toString(String pad)

Methods inherited from class java.lang.Object

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

Constructor Detail

Expression

public Expression(FieldMetaInfo.Optype opType,
                  ArrayList<Attribute> fieldDefs)

Method Detail

setFieldDefs

public void setFieldDefs(ArrayList<Attribute> fieldDefs)
                  throws Exception

Set the field definitions for this Expression to use

Parameters:

fieldDefs - the field definitions to use

Throws:

Exception - if there is a problem setting the field definitions

getResult

public abstract double getResult(double[] incoming)
                          throws Exception

Get the result of evaluating the expression. In the case of a continuous optype, a real number is returned; in the case of a categorical/ordinal optype, the index of the nominal value is returned as a double.

Parameters:

incoming - the incoming parameter values

Returns:

the result of evaluating the expression

Throws:

Exception - if there is a problem computing the result

getResultContinuous

public double getResultContinuous(double[] incoming)
                           throws Exception

Get the result of evaluating the expression for continuous optype. Is the same as calling getResult() when the optype is continuous.

Parameters:

incoming - the incoming parameter values mining schema

Returns:

the result of evaluating the expression.

Throws:

Exception - if the optype is not continuous.

getResultCategorical

public abstract String getResultCategorical(double[] incoming)
                                     throws Exception

Gets the result of evaluating the expression when the optype is categorical or ordinal as the actual String value.

Parameters:

incoming - the incoming parameter values

Returns:

the result of evaluating the expression

Throws:

Exception - if the optype is continuous

getExpression

public static Expression getExpression(Node container,
                                       FieldMetaInfo.Optype opType,
                                       ArrayList<Attribute> fieldDefs,
                                       weka.core.pmml.TransformationDictionary transDict)
                                throws Exception

Static factory method that returns a subclass of Expression that encapsulates the type of expression contained in the Element supplied. Assumes that there is just one expression contained in the supplied Element.

Parameters:

container - the Node containing the expression

opType - the optype of the value returned by this Expression.

fieldDefs - an ArrayList of Attributes for the fields that this Expression may need to access Since Expressions are children of either DerivedFields or DefineFuntions, they will have the same optype as their parent.

transDict - the TransformationDictionary (may be null if there is no dictionary)

Returns:

an Expression object or null if there is no known expression in the container

Throws:

Exception - for unsupported Expression types

getExpression

public static Expression getExpression(String name,
                                       Node expression,
                                       FieldMetaInfo.Optype opType,
                                       ArrayList<Attribute> fieldDefs,
                                       weka.core.pmml.TransformationDictionary transDict)
                                throws Exception

Static factory method that returns a subclass of Expression that encapsulates the type of expression supplied as an argument.

Parameters:

name - the name of the Expression to get

expression - the Node containing the expression

opType - the optype of the value returned by this Expression.

fieldDefs - an ArrayList of Attributes for the fields that this Expression may need to access Since Expressions are children of either DerivedFields or DefineFuntions, they will have the same optype as their parent.

transDict - the TransformationDictionary (may be null if there is no dictionary)

Returns:

an Expression object or null if there is no known expression in the container

Throws:

Exception - for unsupported Expression types

getFieldDef

public Attribute getFieldDef(String attName)

Return the named attribute from the list of reference fields.

Parameters:

attName - the name of the attribute to retrieve

Returns:

the named attribute (or null if it can't be found).

getFieldDefIndex

public int getFieldDefIndex(String attName)

getOptype

public FieldMetaInfo.Optype getOptype()

Get the optype of the result of applying this Expression.

Returns:

the optype of the result of applying this Expression

toString

public String toString()

Overrides:

toString in class Object

toString

public String toString(String pad)