The positionIncrement determines the position of this token relative to the previous Token in a {@link TokenStream}, used in phrase searching.

The default value is one.

Some common uses for this are:

  • Set it to zero to put multiple terms in the same position. This is useful if, e.g., a word has multiple stems. Searches for phrases including either stem will match. In this case, all but the first stem's increment should be set to zero: the increment of the first instance should be one. Repeating a token with an increment of zero can also be used to boost the scores of matches on that token.
  • Set it to values greater than one to inhibit exact phrase matches. If, for example, one does not want phrases to match across removed stop words, then one could build a stop word filter that removes stop words and also sets the increment to the number of stop words removed before each non-stop word. Then exact phrase queries will only match when the terms occur with no intervening stop words.

Namespace: Lucene.Net.Analysis.Tokenattributes
Assembly: Lucene.Net (in Lucene.Net.dll) Version: 2.9.4.1

Syntax

C#
[SerializableAttribute]
public class PositionIncrementAttributeImpl : AttributeImpl, 
	PositionIncrementAttribute, Attribute, ICloneable
Visual Basic
<SerializableAttribute> _
Public Class PositionIncrementAttributeImpl _
	Inherits AttributeImpl _
	Implements PositionIncrementAttribute, Attribute, ICloneable
Visual C++
[SerializableAttribute]
public ref class PositionIncrementAttributeImpl : public AttributeImpl, 
	PositionIncrementAttribute, Attribute, ICloneable

Inheritance Hierarchy

System..::..Object
  Lucene.Net.Util..::..AttributeImpl
    Lucene.Net.Analysis.Tokenattributes..::..PositionIncrementAttributeImpl

See Also