org.apache.lucene.geo

Class GeoUtils

java.lang.Object

org.apache.lucene.geo.GeoUtils

public final class GeoUtils
extends Object

Basic reusable geo-spatial utility methods

WARNING: This API is experimental and might change in incompatible ways in the next release.

Field Summary

Fields

Modifier and Type	Field and Description
static double	EARTH_MEAN_RADIUS_METERS mean earth axis in meters
static double	MAX_LAT_INCL Maximum latitude value.
static double	MAX_LAT_RADIANS max latitude value in radians
static double	MAX_LON_INCL Maximum longitude value.
static double	MAX_LON_RADIANS max longitude value in radians
static double	MIN_LAT_INCL Minimum latitude value.
static double	MIN_LAT_RADIANS min latitude value in radians
static double	MIN_LON_INCL Minimum longitude value.
static double	MIN_LON_RADIANS min longitude value in radians

Method Summary

Modifier and Type	Method and Description
static void	checkLatitude(double latitude) validates latitude value is within standard +/-90 coordinate bounds
static void	checkLongitude(double longitude) validates longitude value is within standard +/-180 coordinate bounds
static double	distanceQuerySortKey(double radius) binary search to find the exact sortKey needed to match the specified radius any sort key lte this is a query match.
static PointValues.Relation	relate(double minLat, double maxLat, double minLon, double maxLon, double lat, double lon, double distanceSortKey, double axisLat) Compute the relation between the provided box and distance query.
static double	sloppySin(double a) Returns the trigonometric sine of an angle converted as a cos operation.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MIN_LON_INCL

public static final double MIN_LON_INCL

Minimum longitude value.

See Also:

Constant Field Values

MAX_LON_INCL

public static final double MAX_LON_INCL

Maximum longitude value.

See Also:

Constant Field Values

MIN_LAT_INCL

public static final double MIN_LAT_INCL

Minimum latitude value.

See Also:

Constant Field Values

MAX_LAT_INCL

public static final double MAX_LAT_INCL

Maximum latitude value.

See Also:

Constant Field Values

MIN_LON_RADIANS

public static final double MIN_LON_RADIANS

min longitude value in radians

See Also:

Constant Field Values

MIN_LAT_RADIANS

public static final double MIN_LAT_RADIANS

min latitude value in radians

See Also:

Constant Field Values

MAX_LON_RADIANS

public static final double MAX_LON_RADIANS

max longitude value in radians

See Also:

Constant Field Values

MAX_LAT_RADIANS

public static final double MAX_LAT_RADIANS

max latitude value in radians

See Also:

Constant Field Values

EARTH_MEAN_RADIUS_METERS

public static final double EARTH_MEAN_RADIUS_METERS

mean earth axis in meters

See Also:

Constant Field Values

Method Detail

checkLatitude

public static void checkLatitude(double latitude)

validates latitude value is within standard +/-90 coordinate bounds

checkLongitude

public static void checkLongitude(double longitude)

validates longitude value is within standard +/-180 coordinate bounds

sloppySin

public static double sloppySin(double a)

Returns the trigonometric sine of an angle converted as a cos operation.

Note that this is not quite right... e.g. sin(0) != 0

Special cases:

• If the argument is NaN or an infinity, then the result is NaN.

Parameters:

a - an angle, in radians.

Returns:

the sine of the argument.

See Also:

Math.sin(double)

distanceQuerySortKey

public static double distanceQuerySortKey(double radius)

binary search to find the exact sortKey needed to match the specified radius any sort key lte this is a query match.

relate

public static PointValues.Relation relate(double minLat,
                                          double maxLat,
                                          double minLon,
                                          double maxLon,
                                          double lat,
                                          double lon,
                                          double distanceSortKey,
                                          double axisLat)

Compute the relation between the provided box and distance query. This only works for boxes that do not cross the dateline.