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.

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static class GeoUtils.WindingOrder
used to define the orientation of 3 points -1 = Clockwise 0 = Colinear 1 = Counter-clockwise

Field Summary

Fields
Modifier and Type	Field	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

All Methods Static Methods Concrete Methods
Modifier and Type	Method	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 boolean`	`lineCrossesLine(double a1x, double a1y, double b1x, double b1y, double a2x, double a2y, double b2x, double b2y)`	uses orient method to compute whether two line segments cross
`static boolean`	`lineCrossesLineWithBoundary(double a1x, double a1y, double b1x, double b1y, double a2x, double a2y, double b2x, double b2y)`	uses orient method to compute whether two line segments cross; boundaries included - returning true for lines that terminate on each other.
`static boolean`	`lineOverlapLine(double a1x, double a1y, double b1x, double b1y, double a2x, double a2y, double b2x, double b2y)`	uses orient method to compute whether two line overlap each other
`static int`	`orient(double ax, double ay, double bx, double by, double cx, double cy)`	Returns a positive value if points a, b, and c are arranged in counter-clockwise order, negative value if clockwise, zero if collinear.
`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
- MIN_LAT_RADIANS
```
public static final double MIN_LAT_RADIANS
```
  min latitude value in radians
- MAX_LON_RADIANS
```
public static final double MAX_LON_RADIANS
```
  max longitude value in radians
- MAX_LAT_RADIANS
```
public static final double MAX_LAT_RADIANS
```
  max latitude value in radians
- 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.

orient

public static int orient(double ax,
                         double ay,
                         double bx,
                         double by,
                         double cx,
                         double cy)

Returns a positive value if points a, b, and c are arranged in counter-clockwise order, negative value if clockwise, zero if collinear.

lineCrossesLine

public static boolean lineCrossesLine(double a1x,
                                      double a1y,
                                      double b1x,
                                      double b1y,
                                      double a2x,
                                      double a2y,
                                      double b2x,
                                      double b2y)

uses orient method to compute whether two line segments cross

lineOverlapLine

public static boolean lineOverlapLine(double a1x,
                                      double a1y,
                                      double b1x,
                                      double b1y,
                                      double a2x,
                                      double a2y,
                                      double b2x,
                                      double b2y)

uses orient method to compute whether two line overlap each other

lineCrossesLineWithBoundary

public static boolean lineCrossesLineWithBoundary(double a1x,
                                                  double a1y,
                                                  double b1x,
                                                  double b1y,
                                                  double a2x,
                                                  double a2y,
                                                  double b2x,
                                                  double b2y)

uses orient method to compute whether two line segments cross; boundaries included - returning true for lines that terminate on each other.

e.g., (plus sign) + == true, and (capital 't') T == true

Use lineCrossesLine(double, double, double, double, double, double, double, double) to exclude lines that terminate on each other from the truth table

Class GeoUtils

Nested Class Summary

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

MIN_LON_INCL

MAX_LON_INCL

MIN_LAT_INCL

MAX_LAT_INCL

MIN_LON_RADIANS

MIN_LAT_RADIANS

MAX_LON_RADIANS

MAX_LAT_RADIANS

EARTH_MEAN_RADIUS_METERS

Method Detail

checkLatitude

checkLongitude

sloppySin

distanceQuerySortKey

relate

orient

lineCrossesLine

lineOverlapLine

lineCrossesLineWithBoundary