Module org.elasticsearch.xcore

Package org.elasticsearch.xpack.core.ml.inference.preprocessing

Class NGram

java.lang.Object

org.elasticsearch.xpack.core.ml.inference.preprocessing.NGram

All Implemented Interfaces:

org.apache.lucene.util.Accountable, NamedWriteable, Writeable, ToXContent, ToXContentObject, LenientlyParsedPreProcessor, PreProcessor, StrictlyParsedPreProcessor, NamedXContentObject

public class NGram
extends Object
implements LenientlyParsedPreProcessor, StrictlyParsedPreProcessor

PreProcessor for n-gram encoding a string

Nested Class Summary

Nested classes/interfaces inherited from interface org.elasticsearch.xpack.core.ml.inference.preprocessing.PreProcessor

PreProcessor.PreProcessorParseContext

Nested classes/interfaces inherited from interface org.elasticsearch.xcontent.ToXContent

ToXContent.DelegatingMapParams, ToXContent.MapParams, ToXContent.Params

Nested classes/interfaces inherited from interface org.elasticsearch.common.io.stream.Writeable

Writeable.Reader<V>, Writeable.Writer<V>

Field Summary

Fields

Modifier and Type	Field	Description
static final ParseField	CUSTOM
static final ParseField	FEATURE_PREFIX
static final ParseField	FIELD
static final ParseField	LENGTH
static final ParseField	NAME
static final ParseField	NGRAMS
static final long	SHALLOW_SIZE
static final ParseField	START

Fields inherited from interface org.apache.lucene.util.Accountable

NULL_ACCOUNTABLE

Fields inherited from interface org.elasticsearch.xcontent.ToXContent

EMPTY, EMPTY_PARAMS

Constructor Summary

Constructors

Constructor	Description
NGram(String field, String featurePrefix, int[] nGrams, int start, int length, boolean custom)
NGram(StreamInput in)

Method Summary

Modifier and Type	Method	Description
boolean	equals(Object o)
static NGram	fromXContentLenient(XContentParser parser, PreProcessor.PreProcessorParseContext context)
static NGram	fromXContentStrict(XContentParser parser, PreProcessor.PreProcessorParseContext context)
String	getFeaturePrefix()
String	getField()
int	getLength()
String	getName()
int[]	getnGrams()
String	getOutputFieldType(String outputField)
int	getStart()
String	getWriteableName()
int	hashCode()
List<String>	inputFields()	The expected input fields
boolean	isCustom()
List<String>	outputFields()
void	process(Map<String,Object> fields)	Process the given fields and their values and return the modified map.
long	ramBytesUsed()
Map<String,String>	reverseLookup()
String	toString()
XContentBuilder	toXContent(XContentBuilder builder, ToXContent.Params params)
void	writeTo(StreamOutput out)

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.lucene.util.Accountable

getChildResources

Methods inherited from interface org.elasticsearch.xcontent.ToXContentObject

isFragment

Field Details

SHALLOW_SIZE

public static final long SHALLOW_SIZE

NAME

public static final ParseField NAME

FIELD

public static final ParseField FIELD

FEATURE_PREFIX

public static final ParseField FEATURE_PREFIX

NGRAMS

public static final ParseField NGRAMS

START

public static final ParseField START

LENGTH

public static final ParseField LENGTH

CUSTOM

public static final ParseField CUSTOM

Constructor Details

NGram

public NGram(String field,
 String featurePrefix,
 int[] nGrams,
 int start,
 int length,
 boolean custom)

NGram

public NGram(StreamInput in)
      throws IOException

Throws:

IOException

Method Details

fromXContentStrict

public static NGram fromXContentStrict(XContentParser parser,
 PreProcessor.PreProcessorParseContext context)

fromXContentLenient

public static NGram fromXContentLenient(XContentParser parser,
 PreProcessor.PreProcessorParseContext context)

writeTo

public void writeTo(StreamOutput out)
             throws IOException

Specified by:

writeTo in interface Writeable

Throws:

IOException

toString

public String toString()

Overrides:

toString in class Object

inputFields

public List<String> inputFields()

Description copied from interface: PreProcessor

The expected input fields

Specified by:

inputFields in interface PreProcessor

outputFields

public List<String> outputFields()

Specified by:

outputFields in interface PreProcessor

Returns:

The resulting output fields. It is imperative that the order is consistent between calls.

process

public void process(Map<String,Object> fields)

Description copied from interface: PreProcessor

Process the given fields and their values and return the modified map. NOTE: The passed map object is mutated directly

Specified by:

process in interface PreProcessor

Parameters:

fields - The fields and their values to process

reverseLookup

public Map<String,String> reverseLookup()

Specified by:

reverseLookup in interface PreProcessor

Returns:

Reverse lookup map to match resulting features to their original feature name

getOutputFieldType

public String getOutputFieldType(String outputField)

Specified by:

getOutputFieldType in interface PreProcessor

ramBytesUsed

public long ramBytesUsed()

Specified by:

ramBytesUsed in interface org.apache.lucene.util.Accountable

getWriteableName

public String getWriteableName()

Specified by:

getWriteableName in interface NamedWriteable

getName

public String getName()

Specified by:

getName in interface NamedXContentObject

Returns:

The name of the XContentObject that is to be serialized

toXContent

public XContentBuilder toXContent(XContentBuilder builder,
 ToXContent.Params params)
                           throws IOException

Specified by:

toXContent in interface ToXContent

Throws:

IOException

getField

public String getField()

getFeaturePrefix

public String getFeaturePrefix()

getnGrams

public int[] getnGrams()

getStart

public int getStart()

getLength

public int getLength()

isCustom

public boolean isCustom()

Specified by:

isCustom in interface PreProcessor

Returns:

Is the pre-processor a custom one provided by the user, or automatically created? This changes how feature importance is calculated, as fields generated by custom processors get individual feature importance calculations.

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object