Detailed Description

Helmert transformations, which are 7-parameter transformations between reference frames (i.e. ECEF position coordinates). A Helmert tranformation is defined by 7 parameters: a rotation(3), a translation(3) and scale factor(1).

Deprecated:: This enum is deprecated as of Dec 2022 and should not be used. Use TransformLibrary or HelmertTransformer instead.

Definition at line 63 of file HelmertTransform.hpp.

#include <HelmertTransform.hpp>

Public Member Functions
std::string	asString () const noexcept

CommonTime	getEpoch () const noexcept
	Get the time at which this transform becomes valid. More...

ReferenceFrame	getFromFrame () const noexcept
	Get the reference frame this transform can convert from (or to). More...

ReferenceFrame	getToFrame () const noexcept
	Get the reference frame this transform can convert to (or from). More...

	HelmertTransform () noexcept
	Default constructor. More...

	HelmertTransform (ReferenceFrame from, ReferenceFrame to, double irx, double iry, double irz, double itx, double ity, double itz, double sc, const std::string &desc, const CommonTime &refEpoch)

void	transform (const Position &pos, Position &result)

void	transform (const Triple &vec, ReferenceFrame frame, Triple &result)

void	transform (const Vector< double > &vec, ReferenceFrame frame, Vector< double > &result)

void	transform (const Xvt &xvt, Xvt &result)

void	transform (double x, double y, double z, ReferenceFrame frame, double &rx, double &ry, double &rz)

Static Public Attributes
static const GNSSTK_EXPORT CommonTime	PZ90Epoch
	Epoch at which GLONASS transitions from PZ90 to PZ90.02. More...

static const GNSSTK_EXPORT int	stdCount = 5
	length of array of pre-defined HelmertTransforms More...

static const GNSSTK_EXPORT HelmertTransform	stdTransforms [stdCount]
	array of all pre-defined HelmertTransforms More...

Protected Attributes
std::string	description

CommonTime	epoch
	epoch at which transform is first applicable More...

ReferenceFrame	fromFrame
	Reference frame to which *this is applied. More...

Matrix< double >	rotation
	the transform 3x3 rotation matrix (w/o scale) More...

double	rx
	X axis rotation in radians. More...

double	ry
	Y axis rotation in radians. More...

double	rz
	Z axis rotation in radians. More...

double	scale
	scale factor, dimensionless, 0=no scale More...

ReferenceFrame	toFrame
	Reference frame resulting from *this transform. More...

Vector< double >	translation
	the transform 3-vector in meters More...

double	tx
	X axis translation in meters. More...

double	ty
	Y axis translation in meters. More...

double	tz
	Z axis translation in meters. More...

Constructor & Destructor Documentation

◆ HelmertTransform() [1/2]

gnsstk::HelmertTransform::HelmertTransform ( )

noexcept

Default constructor.

Definition at line 53 of file HelmertTransform.cpp.

◆ HelmertTransform() [2/2]

gnsstk::HelmertTransform::HelmertTransform	(	ReferenceFrame	from,
		ReferenceFrame	to,
		double	irx,
		double	iry,
		double	irz,
		double	itx,
		double	ity,
		double	itz,
		double	sc,
		const std::string &	desc,
		const CommonTime &	refEpoch
	)

Explicit constructor, from the 7 parameters. All the inputs are unchanged.

This constructor and class are for data to be used with the transformation of the either of the two following forms (view via doxygen).

Warning: If the transformation parameters you wish to use use the transposed version of the rotation matrix (i.e. the signs on the rotation angles are reversed from what is shown below), make sure to flip the sign on the irx,iry,irz parameters to the constructor.

$\left[ {\begin{array}{c} X_{tgt} \\ Y_{tgt} \\ Z_{tgt} \\ \end{array} } \right] = \left[ {\begin{array}{c} T_x \\ T_y \\ T_z \\ \end{array} } \right] + (1 + S_c) \left[ {\begin{array}{ccc} 1 & R_z & -R_y \\ -R_z & 1 & R_x \\ R_y & -R_x & 1 \\ \end{array} } \right] \left[ {\begin{array}{c} X_{src} \\ Y_{src} \\ Z_{src} \\ \end{array} } \right]$

$\left[ {\begin{array}{c} X_{tgt} \\ Y_{tgt} \\ Z_{tgt} \\ \end{array} } \right] = \left[ {\begin{array}{c} X_{src} \\ Y_{src} \\ Z_{src} \\ \end{array} } \right] + \left[ {\begin{array}{c} T_x \\ T_y \\ T_z \\ \end{array} } \right] + \left[ {\begin{array}{ccc} S_c & R_z & -R_y \\ -R_z & S_c & R_x \\ R_y & -R_x & S_c \\ \end{array} } \right] \left[ {\begin{array}{c} X_{src} \\ Y_{src} \\ Z_{src} \\ \end{array} } \right]$

Parameters

[in]	from	Transform takes "from" -> "to"
[in]	to	Transform takes "from" -> "to"
[in]	irx	X axis rotation angle in degrees
[in]	iry	Y axis rotation angle in degrees
[in]	irz	Z axis rotation angle in degrees
[in]	itx	X axis translation in meters
[in]	ity	Y axis translation in meters
[in]	itz	Z axis translation in meters
[in]	sc	scale factor (dimensionless)
[in]	desc	description of the transform, should include
[in]	refEpoch	time when transform became applicable (default=BOT) reference frames and an indication of the source (e.g. literature citation).

Exceptions

InvalidRequest if the transform is invalid.

Note: small angle approximation is used.; by construction, transpose(rotation) == inverse(rotation) (given small angle approximation).

Definition at line 68 of file HelmertTransform.cpp.

Member Function Documentation

◆ asString()

string gnsstk::HelmertTransform::asString ( ) const

noexcept

Dump the object to a multi-line string including reference frames, the 7 parameters and description.

Definition at line 119 of file HelmertTransform.cpp.

◆ getEpoch()

CommonTime gnsstk::HelmertTransform::getEpoch ( ) const

inlinenoexcept

Get the time at which this transform becomes valid.

Definition at line 205 of file HelmertTransform.hpp.

◆ getFromFrame()

ReferenceFrame gnsstk::HelmertTransform::getFromFrame ( ) const

inlinenoexcept

Get the reference frame this transform can convert from (or to).

Definition at line 197 of file HelmertTransform.hpp.

◆ getToFrame()

ReferenceFrame gnsstk::HelmertTransform::getToFrame ( ) const

inlinenoexcept

Get the reference frame this transform can convert to (or from).

Definition at line 201 of file HelmertTransform.hpp.

◆ transform() [1/5]

void gnsstk::HelmertTransform::transform	(	const Position &	pos,
		Position &	result
	)

Transform Position to another frame using this transform or its inverse.

Parameters

[in]	pos	position to be transformed; unchanged on output.
[out]	result	position after transformation.

Exceptions

InvalidRequest if transformation, or inverse, cannot act on ReferenceFrame of input.

Definition at line 151 of file HelmertTransform.cpp.

◆ transform() [2/5]

void gnsstk::HelmertTransform::transform	(	const Triple &	vec,
		ReferenceFrame	frame,
		Triple &	result
	)

Transform a Triple using this Helmert transformation or its inverse.

Parameters

[in]	vec	containing position and frame to be transformed.
[in]	frame	Transform takes "frame" -> "new-frame"
[out]	result	with position in new frame

Exceptions

InvalidRequest if transformation, or inverse, cannot act on ReferenceFrame of input.

Definition at line 220 of file HelmertTransform.cpp.

◆ transform() [3/5]

void gnsstk::HelmertTransform::transform	(	const Vector< double > &	vec,
		ReferenceFrame	frame,
		Vector< double > &	result
	)

Transform a 3-vector, in the given frame, using this Helmert transformation.

Parameters

[in]	vec	3-vector of position coordinates in "from" frame.
[in]	frame	Transform takes "frame" -> "new-frame"
[out]	result	3-vector in "new-frame" frame.

Exceptions

InvalidRequest if transformation, or inverse, cannot act on ReferenceFrame of input.

Definition at line 194 of file HelmertTransform.cpp.

◆ transform() [4/5]

void gnsstk::HelmertTransform::transform	(	const Xvt &	xvt,
		Xvt &	result
	)

Transform an Xvt using this Helmert transformation or its inverse.

Parameters

[in]	xvt	containing position and frame to be transformed.
[out]	result	with position in new frame

Exceptions

InvalidRequest if transformation, or inverse, cannot act on ReferenceFrame of input.

Definition at line 239 of file HelmertTransform.cpp.

◆ transform() [5/5]

void gnsstk::HelmertTransform::transform	(	double	x,
		double	y,
		double	z,
		ReferenceFrame	frame,
		double &	rx,
		double &	ry,
		double &	rz
	)

Transform 3 doubles, in the given frame, using this Helmert transformation.

Parameters

[in]	x,y,z	3-vector of position coordinates in "from" frame.
[in]	frame	Transform takes "frame" -> "new-frame"
[out]	rx,ry,rz	result 3-vector in "new-frame" frame.

Exceptions

InvalidRequest if transformation, or inverse, cannot act on ReferenceFrame of input.

Definition at line 260 of file HelmertTransform.cpp.

Member Data Documentation

◆ description

std::string gnsstk::HelmertTransform::description

protected

an arbitrary string describing the transform; it should include the source.

Definition at line 242 of file HelmertTransform.hpp.

◆ epoch

CommonTime gnsstk::HelmertTransform::epoch

protected

epoch at which transform is first applicable

Definition at line 238 of file HelmertTransform.hpp.

◆ fromFrame

ReferenceFrame gnsstk::HelmertTransform::fromFrame

protected

Reference frame to which *this is applied.

Definition at line 221 of file HelmertTransform.hpp.

◆ PZ90Epoch

const CommonTime gnsstk::HelmertTransform::PZ90Epoch

static

Epoch at which GLONASS transitions from PZ90 to PZ90.02.

Definition at line 209 of file HelmertTransform.hpp.

◆ rotation

Matrix<double> gnsstk::HelmertTransform::rotation

protected

the transform 3x3 rotation matrix (w/o scale)

Definition at line 234 of file HelmertTransform.hpp.

◆ rx

double gnsstk::HelmertTransform::rx

protected

X axis rotation in radians.

Definition at line 225 of file HelmertTransform.hpp.

◆ ry

double gnsstk::HelmertTransform::ry

protected

Y axis rotation in radians.

Definition at line 226 of file HelmertTransform.hpp.

◆ rz

double gnsstk::HelmertTransform::rz

protected

Z axis rotation in radians.

Definition at line 227 of file HelmertTransform.hpp.

◆ scale

double gnsstk::HelmertTransform::scale

protected

scale factor, dimensionless, 0=no scale

Definition at line 231 of file HelmertTransform.hpp.

◆ stdCount

const GNSSTK_EXPORT int gnsstk::HelmertTransform::stdCount = 5

static

length of array of pre-defined HelmertTransforms

Definition at line 212 of file HelmertTransform.hpp.

◆ stdTransforms

const HelmertTransform gnsstk::HelmertTransform::stdTransforms

static

array of all pre-defined HelmertTransforms

Definition at line 215 of file HelmertTransform.hpp.

◆ toFrame

ReferenceFrame gnsstk::HelmertTransform::toFrame

protected

Reference frame resulting from *this transform.

Definition at line 222 of file HelmertTransform.hpp.

◆ translation

Vector<double> gnsstk::HelmertTransform::translation

protected

the transform 3-vector in meters

Definition at line 235 of file HelmertTransform.hpp.

◆ tx

double gnsstk::HelmertTransform::tx

protected

X axis translation in meters.

Definition at line 228 of file HelmertTransform.hpp.

◆ ty

double gnsstk::HelmertTransform::ty

protected

Y axis translation in meters.

Definition at line 229 of file HelmertTransform.hpp.

◆ tz

double gnsstk::HelmertTransform::tz

protected

Z axis translation in meters.

Definition at line 230 of file HelmertTransform.hpp.

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

Detailed Description

Public Member Functions

Static Public Attributes

Protected Attributes

Constructor & Destructor Documentation

◆ HelmertTransform() [1/2]

◆ HelmertTransform() [2/2]

Member Function Documentation

◆ asString()

◆ getEpoch()

◆ getFromFrame()

◆ getToFrame()

◆ transform() [1/5]

◆ transform() [2/5]

◆ transform() [3/5]

◆ transform() [4/5]

◆ transform() [5/5]

Member Data Documentation

◆ description

◆ epoch

◆ fromFrame

◆ PZ90Epoch

◆ rotation

◆ rx

◆ ry

◆ rz

◆ scale

◆ stdCount

◆ stdTransforms

◆ toFrame

◆ translation

◆ tx

◆ ty

◆ tz