Package edu.sc.seis.TauP

Class SphericalCoords

java.lang.Object

edu.sc.seis.TauP.SphericalCoords

public class SphericalCoords
extends Object

Utility class for spherical coordinate (lat-lon) transformations. Given lat, lon, lat, lon you can find the distance or azimuth and given lat, lon, distance, azimuth you can find the lat lon of the resultant point. Just uses spherical relations, no ellpticity correction is applied.

See Appendix A of "Seismology and Plate Tectonics" by David Gubbins Cambridge University Press, 1990

and Chapter 3 of "Plate Tectonics: How it Works" by Allan Cox and Robert Brian Hart Blackwell Scientific Publications, 1986

Field Summary

Fields

Modifier and Type	Field	Description
protected static final double	dtor
static final double	DtoR
static final net.sf.geographiclib.Geodesic	EARTH_SPHERE
static final double	ONE_DEG_AS_RADIAN
protected static final double	rtod
static final double	RtoD
static final double	TWOPI

Constructor Summary

Constructors

Constructor	Description
SphericalCoords()

Method Summary

Modifier and Type	Method	Description
static double	azimuth(double latA, double lonA, double latB, double lonB)	Calculates azimuth between two lat lon pairs.
static double	azimuth(edu.sc.seis.seisFile.LatLonLocatable a, edu.sc.seis.seisFile.LatLonLocatable b)
static double	azimuth(edu.sc.seis.seisFile.Location a, edu.sc.seis.seisFile.Location b)
static double	distance(double latA, double lonA, double latB, double lonB)	Calculates angular distance between two lat lon pairs.
static double	distance(edu.sc.seis.seisFile.Location a, edu.sc.seis.seisFile.Location b)
static double	distanceRadian(double latA, double lonA, double latB, double lonB)
static double	distanceRadian(edu.sc.seis.seisFile.Location a, edu.sc.seis.seisFile.Location b)
static double	distanceTrim180(double deg)
static double	getModuloDistRadian(double distRadian)	returns distance in radians and in the range 0-PI.
static double[]	greatCircleRotationPole(double lat, double lon, double azimuth)
static double	latFor(double latA, double lonA, double distance, double azimuth)	Calculates the latitude of a point a given distance along a given azimuth from a starting lat lon.
static double	latFor(edu.sc.seis.seisFile.Location a, double distance, double azimuth)	Calculates the latitude of a point a given distance along a given azimuth from a starting lat lon.
static double[]	latLonFromXYZ(double[] xyz)
static double	lonFor(double latA, double lonA, double distance, double azimuth)	Calculates the longitude of a point a given distance along a given azimuth from a starting lat lon.
static double	lonFor(edu.sc.seis.seisFile.Location a, double distance, double azimuth)	Calculates the latitude of a point a given distance along a given azimuth from a starting lat lon.
static double[]	rotate(double latA, double lonA, double[] pole, double angleDeg)	rotates a point about a pole by an angle.
static double[]	rotationPole(double latA, double lonA, double latB, double lonB)	Find the rotation pole required to rotate the first lat lon pair to the second.
static double[]	xyzFromLatLonRadius(double lat, double lon, double radius)

Methods inherited from class java.lang.Object

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

Field Details

dtor

protected static final double dtor

See Also:

• Constant Field Values

DtoR

public static final double DtoR

See Also:

• Constant Field Values

ONE_DEG_AS_RADIAN

public static final double ONE_DEG_AS_RADIAN

See Also:

• Constant Field Values

rtod

protected static final double rtod

See Also:

• Constant Field Values

RtoD

public static final double RtoD

See Also:

• Constant Field Values

TWOPI

public static final double TWOPI

See Also:

• Constant Field Values

EARTH_SPHERE

public static final net.sf.geographiclib.Geodesic EARTH_SPHERE

Constructor Details

SphericalCoords

public SphericalCoords()

Method Details

distance

public static double distance(double latA,
 double lonA,
 double latB,
 double lonB)

Calculates angular distance between two lat lon pairs.

distanceRadian

public static double distanceRadian(double latA,
 double lonA,
 double latB,
 double lonB)

distanceRadian

public static double distanceRadian(edu.sc.seis.seisFile.Location a,
 edu.sc.seis.seisFile.Location b)

distance

public static double distance(edu.sc.seis.seisFile.Location a,
 edu.sc.seis.seisFile.Location b)

azimuth

public static double azimuth(double latA,
 double lonA,
 double latB,
 double lonB)

Calculates azimuth between two lat lon pairs.

azimuth

public static double azimuth(edu.sc.seis.seisFile.LatLonLocatable a,
 edu.sc.seis.seisFile.LatLonLocatable b)

azimuth

public static double azimuth(edu.sc.seis.seisFile.Location a,
 edu.sc.seis.seisFile.Location b)

getModuloDistRadian

public static double getModuloDistRadian(double distRadian)

returns distance in radians and in the range 0-PI. Note this may not be the actual distance traveled.

distanceTrim180

public static double distanceTrim180(double deg)

rotationPole

public static double[] rotationPole(double latA,
 double lonA,
 double latB,
 double lonB)

Find the rotation pole required to rotate the first lat lon pair to the second. Just does a cross product.

Returns:

a 3 element double array with the X, Y and Z components of the pole.

rotate

public static double[] rotate(double latA,
 double lonA,
 double[] pole,
 double angleDeg)

rotates a point about a pole by an angle.

Parameters:

pole - is a 3 element double array with X, Y and Z components of the pole.

Returns:

[lat, lon] in array.

latFor

public static double latFor(edu.sc.seis.seisFile.Location a,
 double distance,
 double azimuth)

Calculates the latitude of a point a given distance along a given azimuth from a starting lat lon.

latFor

public static double latFor(double latA,
 double lonA,
 double distance,
 double azimuth)

Calculates the latitude of a point a given distance along a given azimuth from a starting lat lon.

lonFor

public static double lonFor(edu.sc.seis.seisFile.Location a,
 double distance,
 double azimuth)

Calculates the latitude of a point a given distance along a given azimuth from a starting lat lon.

lonFor

public static double lonFor(double latA,
 double lonA,
 double distance,
 double azimuth)

Calculates the longitude of a point a given distance along a given azimuth from a starting lat lon.

latLonFromXYZ

public static double[] latLonFromXYZ(double[] xyz)

xyzFromLatLonRadius

public static double[] xyzFromLatLonRadius(double lat,
 double lon,
 double radius)

greatCircleRotationPole

public static double[] greatCircleRotationPole(double lat,
 double lon,
 double azimuth)