Package org.tribuo.data.columnar

Class ColumnarFeature

java.lang.Object

org.tribuo.Feature

org.tribuo.data.columnar.ColumnarFeature

All Implemented Interfaces:

Serializable, Cloneable, Comparable<Feature>

public class ColumnarFeature
extends Feature

A Feature with extra bookkeeping for use inside the columnar package.

Examples may destroy and recreate Feature instances so don't expect ColumnarFeatures to still be ColumnarFeatures if you probe the Example after construction.

See Also:

• Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
static final String	CONJUNCTION	The string used as the field name of conjunction features.
static final String	JOINER	The joiner between the field name and feature name.

Fields inherited from class org.tribuo.Feature

name, value

Constructor Summary

Constructors

Constructor	Description
ColumnarFeature(String fieldName, double value)	Constructs a ColumnarFeature from the field name.
ColumnarFeature(String fieldName, String columnEntry, double value)	Constructs a ColumnarFeature from the field name, column entry and value.
ColumnarFeature(String firstFieldName, String secondFieldName, String columnEntry, double value)	Constructs a ColumnarFeature which is the conjunction of features from two fields.

Method Summary

Modifier and Type	Method	Description
static String	generateFeatureName(String fieldName, String name)	Generates a feature name based on the field name and the name.
static String	generateFeatureName(String firstFieldName, String secondFieldName, String name)	Generates a feature name used for conjunction features.
String	getColumnEntry()	Gets the columnEntry (i.e., the feature name produced by the FieldExtractor without the fieldName).
String	getFieldName()	Gets the field name.
String	getFirstFieldName()	If it's a conjunction feature, return the first field name.
String	getSecondFieldName()	If it's a conjunction feature, return the second field name.

Methods inherited from class org.tribuo.Feature

clone, compareTo, equals, featureNameComparator, getName, getValue, hashCode, toHTML, toString

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Details

CONJUNCTION

public static final String CONJUNCTION

The string used as the field name of conjunction features.

See Also:

• Constant Field Values

JOINER

public static final String JOINER

The joiner between the field name and feature name.

See Also:

• Constant Field Values

Constructor Details

ColumnarFeature

public ColumnarFeature(String fieldName,
 double value)

Constructs a ColumnarFeature from the field name. The column entry is blank.

This produces a ColumnarFeature which is identical to a Feature.

Parameters:

fieldName - The field name.

value - The feature value.

ColumnarFeature

public ColumnarFeature(String fieldName,
 String columnEntry,
 double value)

Constructs a ColumnarFeature from the field name, column entry and value.

Parameters:

fieldName - The field name.

columnEntry - The name of the extracted value from the field.

value - The feature value.

ColumnarFeature

public ColumnarFeature(String firstFieldName,
 String secondFieldName,
 String columnEntry,
 double value)

Constructs a ColumnarFeature which is the conjunction of features from two fields.

Parameters:

firstFieldName - The first field name.

secondFieldName - The second field name.

columnEntry - The name of the extracted value from the field.

value - The feature value.

Method Details

generateFeatureName

public static String generateFeatureName(String fieldName,
 String name)

Generates a feature name based on the field name and the name.

Uses JOINER to join the strings.

Parameters:

fieldName - The field name.

name - The name of the extracted feature.

Returns:

The new feature name.

generateFeatureName

public static String generateFeatureName(String firstFieldName,
 String secondFieldName,
 String name)

Generates a feature name used for conjunction features.

Uses JOINER to join the strings and CONJUNCTION to prepend the name.

Parameters:

firstFieldName - The name of the first field.

secondFieldName - The name of the second field.

name - The name of the extracted feature.

Returns:

The new feature name.

getFieldName

public String getFieldName()

Gets the field name. Returns CONJUNCTION if it's a conjunction.

Returns:

The field name.

getFirstFieldName

public String getFirstFieldName()

If it's a conjunction feature, return the first field name. Otherwise return an empty String.

Returns:

The first field name, or an empty string.

getSecondFieldName

public String getSecondFieldName()

If it's a conjunction feature, return the second field name. Otherwise return an empty String.

Returns:

The second field name, or an empty string.

getColumnEntry

public String getColumnEntry()

Gets the columnEntry (i.e., the feature name produced by the FieldExtractor without the fieldName).

Returns:

The feature's column entry.