The Location Class manages a single point in/on the Earth, which is described by the GRS80 ellipsoid. More...

#include <Location.h>

Inheritance diagram for slbm::Location:

Public Member Functions
	Location ()

virtual	~Location ()

	Location (const Location &location)

	Location (const double &lat, const double &lon, const double &depth=0)

	Location (const double v[], const double &radius)

	Location (const Location &loc1, const Location &loc2)

Location &	operator= (const Location &other)

bool	operator== (const Location &other) const

bool	operator!= (const Location &other)

string	toString () const

void	setLocation (const double &lat, const double &lon, const double &depth)

void	setLocation (const double *u, const double &r)

void	setRadius (const double &r)

double	getRadius () const

double	getEarthRadius () const

double	getDepth () const

void	setDepth (const double &depth)

double	distance (const Location &other) const

double	distanceKm (Location &other) const

double	distanceDegrees (const Location &other) const

double	azimuth (const Location &other) const
	Find the azimuth from this Location to some other Location. Result will be between 0 and 2*PI radians. More...

double	azimuthDegrees (const Location &other) const
	Find the azimuth from this Location to some other Location. Result will be between 0 and 360 degrees. More...

double	azimuth (const Location &other, const double &errorValue) const
	Find the azimuth from this Location to some other Location. Result will be between 0 and 2*PI radians. If current position is the north or south pole, or if current position and other position are conincident, returns specified errorValue. More...

double	azimuthDegrees (const Location &other, const double &errorValue) const
	Find the azimuth from this Location to some other Location. Result will be between 0 and 360 degrees. If current position is the north or south pole, or if current position and other position are conincident, returns specified errorValue. More...

double	getLat () const
	Retrieve the geographic latitude of this Location, radians. More...

double	getGeocentricLat () const
	Retrieve the geocentric latitude of this Location, radians. More...

double	getGeocentricLatDegrees () const
	Retrieve the geocentric latitude of this Location, degrees. More...

double	getLon () const
	Retrieve the longitude of this Location. Value will be between -PI and PI radians. More...

double	getLatDegrees () const
	Retrieve the geographic latitude of this Location, degrees. More...

double	getLonDegrees () const
	Retrieve the longitude of this Location. Value will be between -180 and 180 degrees. More...

const double *	getUnitVector ()

void	getUnitVector (double x[3])

void	setUnitVector (double x[3])

void	move (const double &azimuth, const double &distance, Location &loc) const
	Retrieve a Location that is a specified distance away from this Location, in a specified direction. More...

bool	cross (const Location &x, Location &loc) const

void	rotate (Location &pole, double angle, Location &loc) const

bool	vectorTripleProduct (const Location &other, double vtp[]) const
	Compute the vector triple product (this x other) x this, normalized to unit length. Returns true if valid, false if triple product has zero length, which will happen when this and other are coincident or PI radians apart. More...

void	move (const double vtp[], const double &a, Location &loc) const
	Move this Location object a specified angular distance (radians) in the direction specified by vtp. More...

void	move_north (const double x[], const double &distance, double z[]) const

void	move_north (const double &distance, Location &loc) const

void	rotate (const double x[], const double p[], const double &a, double z[]) const

double	scalarTripleProduct (const Location &loc1, const Location &loc2) const

double	scalarTripleProduct (const double u[], const double w[]) const

double	scalarTripleProduct (const double u[], const double v[], const double w[]) const

bool	vectorTripleProduct (const double u[], const double v[], double vtp[]) const
	Compute the normalized vector triple product (u x v) x u and and store result in vtp. More...

bool	vectorTripleProductNorthPole (const double u[], double w[]) const
	Compute the normalized vector triple product (u x northPole) x u and store result in w. Returns true if w has finite length, false if length(w) is zero. More...

void	move (const double v[], const double vtp[], const double &a, double u[]) const
	Move unit vector v in direction of vtp by distance a and store result in u. vtp is assumed to be a unit vector normal to v. More...

double	angle (const double u[], const double v[]) const

double	dot (const Location &other) const

double	dot (const double u[], const double v[]) const

double	cross (const double u[], const double v[], double w[]) const

double	crossNorth (const double u[], double w[]) const

double	normalize (double v[]) const

double	length (const double v[]) const

Static Public Member Functions
static int	getClassCount ()

Static Public Attributes
static double	EARTH_RADIUS

Protected Attributes
double	v [3]

double	radius

Static Protected Attributes
static int	locationClassCount

Detailed Description

The Location Class manages a single point in/on the Earth, which is described by the GRS80 ellipsoid.

The Location Class manages a single point in/on the Earth, which is described by the GRS80 ellipsoid. See geovectors.pdf for a thorough mathematical description of Location.

There is a parameterized constructor that takes a geographic latitude, longitude and depth as parameters and converts them to internal representation. There are also many methods for computing the distance between 2 Location objects, the azimuth from one Location to another, the radius of the Earth at a given location, retreiving points along a great circle path between two Location objects, etc.

Definition at line 59 of file Location.h.

Constructor & Destructor Documentation

◆ Location() [1/5]

slbm::Location::Location ( )

◆ ~Location()

virtual slbm::Location::~Location ( )

virtual

◆ Location() [2/5]

slbm::Location::Location ( const Location & location )

◆ Location() [3/5]

slbm::Location::Location	(	const double &	lat,
		const double &	lon,
		const double &	depth = `0`
	)

◆ Location() [4/5]

slbm::Location::Location	(	const double	v[],
		const double &	radius
	)

◆ Location() [5/5]

slbm::Location::Location	(	const Location &	loc1,
		const Location &	loc2
	)

Parameterized constructor. Returns a new Location which is the mean of the two specified Locations.

Member Function Documentation

◆ angle()

double slbm::Location::angle	(	const double	u[],
		const double	v[]
	)		const

inline

Angular distance between two 3-component unit vectors, in radians. Vectors are assumed to be unit length on input.

Parameters

u	unit vector one.
v	unit vector two.

Returns: angular separation in radians.

Definition at line 779 of file Location.h.

◆ azimuth() [1/2]

double slbm::Location::azimuth ( const Location & other ) const

inline

Find the azimuth from this Location to some other Location. Result will be between 0 and 2*PI radians.

Parameters

other the other location to which the azimuth is requested.

Returns: the azimuth from this to other, in radians clockwise from north.

Definition at line 593 of file Location.h.

◆ azimuth() [2/2]

double slbm::Location::azimuth	(	const Location &	other,
		const double &	errorValue
	)		const

inline

Find the azimuth from this Location to some other Location. Result will be between 0 and 2*PI radians. If current position is the north or south pole, or if current position and other position are conincident, returns specified errorValue.

Parameters

other	the other location to which the azimuth is requested.
errorValue	the value to return when things go badly.

Returns: the azimuth from this to other, in radians clockwise from north. If current position is the north or south pole, or if current position and other position are conincident, returns specified errorValue.

Definition at line 598 of file Location.h.

◆ azimuthDegrees() [1/2]

double slbm::Location::azimuthDegrees ( const Location & other ) const

inline

Find the azimuth from this Location to some other Location. Result will be between 0 and 360 degrees.

Parameters

other the other location to which the azimuth is requested.

Returns: the azimuth from this to other, in degrees clockwise from north.

Definition at line 624 of file Location.h.

◆ azimuthDegrees() [2/2]

double slbm::Location::azimuthDegrees	(	const Location &	other,
		const double &	errorValue
	)		const

inline

Find the azimuth from this Location to some other Location. Result will be between 0 and 360 degrees. If current position is the north or south pole, or if current position and other position are conincident, returns specified errorValue.

Parameters

other	the other location to which the azimuth is requested.
errorValue	the value to return when things go badly.

Returns: the azimuth from this to other, in degrees clockwise from north. If current position is the north or south pole, or if current position and other position are conincident, returns specified errorValue.

Definition at line 629 of file Location.h.

◆ cross() [1/2]

double slbm::Location::cross	(	const double	u[],
		const double	v[],
		double	w[]
	)		const

inline

normalized cross product of two 3-component unit vectors.

Parameters

u	vector<double> vector one.
v	vector<double> vector two.
w	set to u cross v, normalized to unit length. If u cross v has zero length, w will equal (0,0,0).

Returns: the length of u cross v prior to normalization. Guaranteed >= 0.

Definition at line 809 of file Location.h.

◆ cross() [2/2]

bool slbm::Location::cross	(	const Location &	x,
		Location &	loc
	)		const

inline

Retrieve a Location which is normal to the plane containing the great circle path from this Location to another Location. Considering the Locations to be unit vectors, loc will be set to this cross x. The radius of the resulting vector will be set to radius of this Location. If this Location and Location x are parallel, then the resulting Location will be invalid (vector will have zero length) and the radius will be -1 km.

Parameters

x	the other Location which, together with this Location, define the great circle path.
loc	the Location normal to the plane containing the great circle path. Invalid if this and loc are parallel.

Returns: true if loc is valid, false if this and x are parallel.

Definition at line 798 of file Location.h.

◆ crossNorth()

double slbm::Location::crossNorth	(	const double	u[],
		double	w[]
	)		const

inline

normalized cross product of a 3-component unit vector with the north pole.

Parameters

u	vector<double> vector one.
w	set to u cross north, normalized to unit length. If u cross north has zero length, w will equal (0,0,0).

Returns: the length of u cross north prior to normalization. Guaranteed >= 0.

Definition at line 820 of file Location.h.

◆ distance()

double slbm::Location::distance ( const Location & other ) const

inline

Returns the distance, in radians, from this Location to some other Location.

Parameters

other the other Location to which this Location is to be compared.

Returns: double separation of the locations in radians.

Definition at line 583 of file Location.h.

◆ distanceDegrees()

double slbm::Location::distanceDegrees ( const Location & other ) const

inline

Return the distance, in degrees, from this Location to some other Location.

Parameters

other the other Location to which this Location is to be compared.

Returns: double separation of the Locations in degrees.

Definition at line 588 of file Location.h.

◆ distanceKm()

double slbm::Location::distanceKm ( Location & other ) const

◆ dot() [1/2]

double slbm::Location::dot	(	const double	u[],
		const double	v[]
	)		const

inline

Dot product of two 3-component unit vectors.

Parameters

u	vector one.
v	vector two.

Returns: dot product.

Definition at line 790 of file Location.h.

◆ dot() [2/2]

double slbm::Location::dot ( const Location & other ) const

inline

Dot product of the unit vector that backs this Location and the unit vector that backs Location other.

Parameters

other the other Location

Returns: dot product.

Definition at line 784 of file Location.h.

◆ getClassCount()

static int slbm::Location::getClassCount ( )

static

◆ getDepth()

double slbm::Location::getDepth ( ) const

inline

Retrieve the depth of this Location.

Returns: the depth of this Location in km.

Definition at line 573 of file Location.h.

◆ getEarthRadius()

double slbm::Location::getEarthRadius ( ) const

Retrieve the radius of the Earth at the latitude of this Location.

Returns: the radius of the Earth in km.

◆ getGeocentricLat()

double slbm::Location::getGeocentricLat ( ) const

inline

Retrieve the geocentric latitude of this Location, radians.

Retrieve the latitude of this Location.

Returns: geocentric latitude, in radians.

Definition at line 250 of file Location.h.

◆ getGeocentricLatDegrees()

double slbm::Location::getGeocentricLatDegrees ( ) const

inline

Retrieve the geocentric latitude of this Location, degrees.

Retrieve the latitude of this Location.

Returns: geocentric latitude, in degrees.

Definition at line 257 of file Location.h.

◆ getLat()

double slbm::Location::getLat ( ) const

inline

Retrieve the geographic latitude of this Location, radians.

Retrieve the latitude of this Location.

Returns: geographic latitude, in radians.

Definition at line 542 of file Location.h.

◆ getLatDegrees()

double slbm::Location::getLatDegrees ( ) const

inline

Retrieve the geographic latitude of this Location, degrees.

Retrieve the latitude of this Location.

Returns: geographic latitude, in degrees.

Definition at line 553 of file Location.h.

◆ getLon()

double slbm::Location::getLon ( ) const

inline

Retrieve the longitude of this Location. Value will be between -PI and PI radians.

Returns: longitude, in radians.

Definition at line 548 of file Location.h.

◆ getLonDegrees()

double slbm::Location::getLonDegrees ( ) const

inline

Retrieve the longitude of this Location. Value will be between -180 and 180 degrees.

Returns: longitude, in degrees.

Definition at line 558 of file Location.h.

◆ getRadius()

double slbm::Location::getRadius ( ) const

inline

Retrieve the radius of this Location object.

Returns: the radius in km.

Definition at line 563 of file Location.h.

◆ getUnitVector() [1/2]

const double* slbm::Location::getUnitVector ( )

inline

Definition at line 282 of file Location.h.

◆ getUnitVector() [2/2]

void slbm::Location::getUnitVector ( double x[3] )

inline

Definition at line 284 of file Location.h.

◆ length()

double slbm::Location::length ( const double v[] ) const

inline

Find the length of a 3-element vector.

Returns: the length of the vector. Guaranteed to be >= 0.

Definition at line 859 of file Location.h.

◆ move() [1/3]

void slbm::Location::move	(	const double &	azimuth,
		const double &	distance,
		Location &	loc
	)		const

inline

Retrieve a Location that is a specified distance away from this Location, in a specified direction.

Retrieve a Location that is a specified distance away from this Location, in a specified direction. The returned Location will have the same radius as this location.

Parameters

azimuth	the azimuth from this Location to the desired Location, in radians, measured clockwise from north.
distance	the distance from this Location to the desired Location, in radians.
loc	the Location that has been moved relative to this Location.

Definition at line 638 of file Location.h.

◆ move() [2/3]

void slbm::Location::move	(	const double	v[],
		const double	vtp[],
		const double &	a,
		double	u[]
	)		const

inline

Move unit vector v in direction of vtp by distance a and store result in u. vtp is assumed to be a unit vector normal to v.

Definition at line 679 of file Location.h.

◆ move() [3/3]

void slbm::Location::move	(	const double	vtp[],
		const double &	a,
		Location &	loc
	)		const

inline

Move this Location object a specified angular distance (radians) in the direction specified by vtp.

Move this Location object a specified angular distance (radians) in the direction specified by vtp, which is assumed to be a unit vector normal to this Location object's unit vector. vtp values are typically obtained by calling Location::vectorTripleProduct().

Parameters

vtp	a 3 component unit vector normal to this Location.
a	the angular distance from this Location to the desired Location, in radians.
loc	the Location object which has been relocated as requested.

Definition at line 670 of file Location.h.

◆ move_north() [1/2]

void slbm::Location::move_north	(	const double &	distance,
		Location &	loc
	)		const

inline

Return a location on the earth that is distance radians due north of this Location. If this is already at the north or south pole, then it is returned unmodified.

Parameters

distance	the distance, in radians, that x is to be moved toward the north.
loc	the Location after having moved distance north.

Definition at line 660 of file Location.h.

◆ move_north() [2/2]

void slbm::Location::move_north	(	const double	x[],
		const double &	distance,
		double	z[]
	)		const

inline

Return a location on the earth that is distance radians due north of positon x. If x is already at the north or south pole, then it is returned unmodified.

Parameters

x	the position to be moved.
distance	the distance, in radians, that x is to be moved toward the north.
z	the 3-element unit vector representing the position after having moved distance north.

Definition at line 651 of file Location.h.

◆ normalize()

double slbm::Location::normalize ( double v[] ) const

inline

Normalizes the input vector to unit length. Returns the length of the vector prior to normalization.

Parameters

v	vector<double>

Returns: length of the vector prior to normalization ( >= 0.)

Definition at line 842 of file Location.h.

◆ operator!=()

bool slbm::Location::operator!= ( const Location & other )

inline

Equality operator. Returns false if other Location object has the exact same horizontal position and radius as this Location object.

Definition at line 113 of file Location.h.

◆ operator=()

Location& slbm::Location::operator= ( const Location & other )

◆ operator==()

bool slbm::Location::operator== ( const Location & other ) const

◆ rotate() [1/2]

void slbm::Location::rotate	(	const double	x[],
		const double	p[],
		const double &	a,
		double	z[]
	)		const

inline

rotate 3d vector x clockwise around 3d vector p, by angle a. x and p are assumed to be unit vectors on input.

Parameters

x	vector to be rotated
p	pole about which rotation is to occur.
a	double the amount of rotation, in radians.
z	the rotated vector, normalized to unit length.

Definition at line 754 of file Location.h.

◆ rotate() [2/2]

void slbm::Location::rotate	(	Location &	pole,
		double	angle,
		Location &	loc
	)		const

inline

Rotate this Location around Location pole by angle a. When looking in direction of pole's unit vector, clockwise rotation is positive.

Parameters

pole	the pole around which this Location is to be rotated.
angle	the angular distance by which this Location is to be rotated around pole, in radians.
loc	the Location that results from rotating this Location around pole.

Definition at line 747 of file Location.h.

◆ scalarTripleProduct() [1/3]

double slbm::Location::scalarTripleProduct	(	const double	u[],
		const double	v[],
		const double	w[]
	)		const

inline

Return the scalar triple product (u cross v) dot w. If all are unit vectors, then the result is cos(phi) where phi is the angle between w and u cross c.

Definition at line 732 of file Location.h.

◆ scalarTripleProduct() [2/3]

double slbm::Location::scalarTripleProduct	(	const double	u[],
		const double	w[]
	)		const

inline

Return the scalar triple product of u, w, and this Location objects unit vector. In other words (u cross w) dot v. If u and w are unit vectors, then the result is cos(phi) where phi is the angle between this Location and u cross w.

Definition at line 739 of file Location.h.

◆ scalarTripleProduct() [3/3]

double slbm::Location::scalarTripleProduct	(	const Location &	loc1,
		const Location &	loc2
	)		const

inline

Return the scalar triple product of loc1, loc2 and this. In other words (loc1 cross loc2) dot this. Since these are all unit vectors, the the result is cos(phi) where phi is the angle between this Location and loc1 cross loc2.

Definition at line 727 of file Location.h.

◆ setDepth()

void slbm::Location::setDepth ( const double & depth )

inline

Set the depth of this Location.

Parameters

depth the desired depth in km.

Definition at line 578 of file Location.h.

◆ setLocation() [1/2]

void slbm::Location::setLocation	(	const double &	lat,
		const double &	lon,
		const double &	depth
	)

inline

Set the location of this Location.

Parameters

lat	the geographic latitude in radians.
lon	the geographic longitude in radians.
depth	the depth in km.

Definition at line 527 of file Location.h.

◆ setLocation() [2/2]

void slbm::Location::setLocation	(	const double *	u,
		const double &	r
	)

inline

Set the location of this Location.

Parameters

u	unit vector of new position.
r	radius of new position in km.

Definition at line 133 of file Location.h.

◆ setRadius()

void slbm::Location::setRadius ( const double & r )

inline

Set the radius of this Location.

Parameters

r	the radius in km.

Definition at line 568 of file Location.h.

◆ setUnitVector()

void slbm::Location::setUnitVector ( double x[3] )

inline

Definition at line 286 of file Location.h.

◆ toString()

string slbm::Location::toString ( ) const

inline

Returns a convenient string representation of this Location.

Definition at line 866 of file Location.h.

◆ vectorTripleProduct() [1/2]

bool slbm::Location::vectorTripleProduct	(	const double	u[],
		const double	v[],
		double	vtp[]
	)		const

inline

Compute the normalized vector triple product (u x v) x u and and store result in vtp.

Compute the normalized vector triple product (u x v) x u and and store result in vtp. Returns true if vtp has finite length, false if length(vtp) is zero.

Definition at line 698 of file Location.h.

◆ vectorTripleProduct() [2/2]

bool slbm::Location::vectorTripleProduct	(	const Location &	other,
		double	vtp[]
	)		const

inline

Compute the vector triple product (this x other) x this, normalized to unit length. Returns true if valid, false if triple product has zero length, which will happen when this and other are coincident or PI radians apart.

Definition at line 691 of file Location.h.

◆ vectorTripleProductNorthPole()

bool slbm::Location::vectorTripleProductNorthPole	(	const double	u[],
		double	w[]
	)		const

inline

Compute the normalized vector triple product (u x northPole) x u and store result in w. Returns true if w has finite length, false if length(w) is zero.

Definition at line 718 of file Location.h.

Member Data Documentation

◆ EARTH_RADIUS

double slbm::Location::EARTH_RADIUS

static

This variable is initialized to -1 in Location.cc, outside the class definition. There is a method SlbmInterface::fixEarthRadius(double) that will modify this value. If this value is less than zero, then Location::getEarthRadius() will return the radius of the earth that is a function of geocentric latitude (larger at the equator, smaller at the poles). If this value is > 0, then getEarthRadius() returns this value.

Definition at line 502 of file Location.h.

◆ locationClassCount

int slbm::Location::locationClassCount

staticprotected

Definition at line 508 of file Location.h.

◆ radius

double slbm::Location::radius

protected

The distance from the center of the earth to this location in km.

Definition at line 521 of file Location.h.

◆ v

double slbm::Location::v[3]

protected

v is the geocentric unit vector that describes the position on the earth. The origin of the vector is at the center of the earth. The x-component points to lon,lat = 0,0. y-component points to lon,lat = PI/2,0 and the z-component points to lon,lat = 0,PI/2.

Definition at line 516 of file Location.h.

The documentation for this class was generated from the following file:

rstt/SLBM/include/Location.h

Public Member Functions

Static Public Member Functions

Static Public Attributes

Protected Attributes

Static Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ Location() [1/5]

◆ ~Location()

◆ Location() [2/5]

◆ Location() [3/5]

◆ Location() [4/5]

◆ Location() [5/5]

Member Function Documentation

◆ angle()

◆ azimuth() [1/2]

◆ azimuth() [2/2]

◆ azimuthDegrees() [1/2]

◆ azimuthDegrees() [2/2]

◆ cross() [1/2]

◆ cross() [2/2]

◆ crossNorth()

◆ distance()

◆ distanceDegrees()

◆ distanceKm()

◆ dot() [1/2]

◆ dot() [2/2]

◆ getClassCount()

◆ getDepth()

◆ getEarthRadius()

◆ getGeocentricLat()

◆ getGeocentricLatDegrees()

◆ getLat()

◆ getLatDegrees()

◆ getLon()

◆ getLonDegrees()

◆ getRadius()

◆ getUnitVector() [1/2]

◆ getUnitVector() [2/2]

◆ length()

◆ move() [1/3]

◆ move() [2/3]

◆ move() [3/3]

◆ move_north() [1/2]

◆ move_north() [2/2]

◆ normalize()

◆ operator!=()

◆ operator=()

◆ operator==()

◆ rotate() [1/2]

◆ rotate() [2/2]

◆ scalarTripleProduct() [1/3]

◆ scalarTripleProduct() [2/3]

◆ scalarTripleProduct() [3/3]

◆ setDepth()

◆ setLocation() [1/2]

◆ setLocation() [2/2]

◆ setRadius()

◆ setUnitVector()

◆ toString()

◆ vectorTripleProduct() [1/2]

◆ vectorTripleProduct() [2/2]

◆ vectorTripleProductNorthPole()

Member Data Documentation

◆ EARTH_RADIUS

◆ locationClassCount

◆ radius

◆ v