PointValues

Access to indexed numeric values.

Points represent numeric values and are indexed differently than ordinary text. Instead of an inverted index, points are indexed with datastructures such as KD-trees. These structures are optimized for operations such as range, distance, nearest-neighbor, and point-in-polygon queries.

Basic Point Types

• in the lucene-sandbox jar
  
  

Basic Lucene point types behave like their java peers: for example IntPoint represents a signed 32-bit Integer, supporting values ranging from Integer.MIN_VALUE to Integer.MAX_VALUE, ordered consistent with Integer.compareTo. In addition to indexing support, point classes also contain static methods (such as IntPoint.newRangeQuery) for creating common queries. For example:

// add year 1970 to document
document.add(new IntPoint("year", 1970));
// index document
writer.addDocument(document);
...
// issue range query of 1960-1980
Query query = IntPoint.newRangeQuery("year", 1960, 1980);
TopDocs docs = searcher.search(query, ...);

Geospatial Point Types

Although basic point types such as DoublePoint support points in multi-dimensional space too, Lucene has specialized classes for location data. These classes are optimized for location data: they are more space-efficient and support special operations such as distance and polygon queries. There are currently two implementations:

1. LatLonPoint: indexes (latitude,longitude) as (x,y) in two-dimensional space.

2. {@docRoot}/../spatial3d/org/apache/lucene/spatial3d/Geo3DPoint.html* in lucene-spatial3d: indexes (latitude,longitude) as (x,y,z) in three-dimensional space.

• does not support altitude, 3D here means "uses three dimensions under-the-hood"
  
  

Advanced usage

Custom structures can be created on top of single- or multi- dimensional basic types, on top of BinaryPoint for more flexibility, or via custom Field subclasses.

Inheritors