Quaternion

Detailed Description

Classes
class	cv::DualQuat< _Tp >
class	cv::Quat< _Tp >
class	cv::QuatEnum

Typedefs
using	cv::DualQuatd = DualQuat<double>
using	cv::DualQuatf = DualQuat<float>
using	cv::Quatd = Quat<double>
using	cv::Quatf = Quat<float>

Enumerations
enum	cv::QuatAssumeType {   cv::QUAT_ASSUME_NOT_UNIT ,   cv::QUAT_ASSUME_UNIT }
	Unit quaternion flag. More...

Functions
template<typename T >
Quat< T >	cv::acos (const Quat< T > &q)
template<typename T >
Quat< T >	cv::acosh (const Quat< T > &q)
template<typename T >
Quat< T >	cv::asin (const Quat< T > &q)
template<typename T >
Quat< T >	cv::asinh (const Quat< T > &q)
template<typename T >
Quat< T >	cv::atan (const Quat< T > &q)
template<typename T >
Quat< T >	cv::atanh (const Quat< T > &q)
template<typename T >
Quat< T >	cv::cos (const Quat< T > &q)
template<typename T >
Quat< T >	cv::cosh (const Quat< T > &q)
template<typename T >
Quat< T >	cv::crossProduct (const Quat< T > &p, const Quat< T > &q)
template<typename T >
Quat< T >	cv::exp (const Quat< T > &q)
template<typename T >
Quat< T >	cv::inv (const Quat< T > &q, QuatAssumeType assumeUnit=QUAT_ASSUME_NOT_UNIT)
template<typename T >
Quat< T >	cv::log (const Quat< T > &q, QuatAssumeType assumeUnit=QUAT_ASSUME_NOT_UNIT)
template<typename T >
Quat< T >	cv::operator* (const Quat< T > &, const T)
template<typename T >
Quat< T >	cv::operator* (const T, const Quat< T > &)
template<typename _Tp >
std::ostream &	cv::operator<< (std::ostream &, const DualQuat< _Tp > &)
template<typename _Tp >
std::ostream &	cv::operator<< (std::ostream &, const Quat< _Tp > &)
template<typename S >
std::ostream &	cv::operator<< (std::ostream &, const Quat< S > &)
template<typename T >
Quat< T >	cv::power (const Quat< T > &q, const Quat< T > &p, QuatAssumeType assumeUnit=QUAT_ASSUME_NOT_UNIT)
template<typename T >
Quat< T >	cv::power (const Quat< T > &q, const T x, QuatAssumeType assumeUnit=QUAT_ASSUME_NOT_UNIT)
template<typename T >
Quat< T >	cv::sin (const Quat< T > &q)
template<typename T >
Quat< T >	cv::sinh (const Quat< T > &q)
template<typename S >
Quat< S >	cv::sqrt (const Quat< S > &q, QuatAssumeType assumeUnit=QUAT_ASSUME_NOT_UNIT)
template<typename T >
Quat< T >	cv::tan (const Quat< T > &q)
template<typename T >
Quat< T >	cv::tanh (const Quat< T > &q)

Typedef Documentation

DualQuatd

using cv::DualQuatd = DualQuat<double>

#include <opencv2/core/dualquaternion.hpp>

DualQuatf

using cv::DualQuatf = DualQuat<float>

#include <opencv2/core/dualquaternion.hpp>

Quatd

using cv::Quatd = Quat<double>

#include <opencv2/core/quaternion.hpp>

Quatf

using cv::Quatf = Quat<float>

#include <opencv2/core/quaternion.hpp>

Enumeration Type Documentation

QuatAssumeType

enum cv::QuatAssumeType

#include <opencv2/core/quaternion.hpp>

Unit quaternion flag.

Enumerator
QUAT_ASSUME_NOT_UNIT  Python: cv.QUAT_ASSUME_NOT_UNIT	This flag is specified by default. If this flag is specified, the input quaternions are assumed to be not unit quaternions. It can guarantee the correctness of the calculations, although the calculation speed will be slower than the flag QUAT_ASSUME_UNIT.
QUAT_ASSUME_UNIT  Python: cv.QUAT_ASSUME_UNIT	If this flag is specified, the input quaternions are assumed to be unit quaternions which will save some computations. However, if this flag is specified without unit quaternion, the program correctness of the result will not be guaranteed.

Function Documentation

acos()

template<typename T >

Quat< T > cv::acos

(

const Quat< T > &

q

)

#include <opencv2/core/quaternion.hpp>

\[\arccos(q) = -\frac{\boldsymbol{v}}{||\boldsymbol{v}||}arccosh(q)\]

where \(\boldsymbol{v} = [x, y, z].\)

Parameters

q	a quaternion.

For example

Quatd q(1,2,3,4);
acos(q);

acosh()

template<typename T >

Quat< T > cv::acosh

(

const Quat< T > &

q

)

#include <opencv2/core/quaternion.hpp>

\[arccosh(q) = \ln(q + \sqrt{q^2 - 1})\]

.

Parameters

q	a quaternion.

For example

Quatd q(1,2,3,4);
acosh(q);

asin()

template<typename T >

Quat< T > cv::asin

(

const Quat< T > &

q

)

#include <opencv2/core/quaternion.hpp>

\[\arcsin(q) = -\frac{\boldsymbol{v}}{||\boldsymbol{v}||}arcsinh(q\frac{\boldsymbol{v}}{||\boldsymbol{v}||})\]

where \(\boldsymbol{v} = [x, y, z].\)

Parameters

q	a quaternion.

For example

Quatd q(1,2,3,4);
asin(q);

asinh()

template<typename T >

Quat< T > cv::asinh

(

const Quat< T > &

q

)

#include <opencv2/core/quaternion.hpp>

\[arcsinh(q) = \ln(q + \sqrt{q^2 + 1})\]

.

Parameters

q	a quaternion.

For example

Quatd q(1,2,3,4);
asinh(q);

atan()

template<typename T >

Quat< T > cv::atan

(

const Quat< T > &

q

)

#include <opencv2/core/quaternion.hpp>

\[\arctan(q) = -\frac{\boldsymbol{v}}{||\boldsymbol{v}||}arctanh(q\frac{\boldsymbol{v}}{||\boldsymbol{v}||})\]

where \(\boldsymbol{v} = [x, y, z].\)

Parameters

q	a quaternion.

For example

Quatd q(1,2,3,4);
atan(q);

atanh()

template<typename T >

Quat< T > cv::atanh

(

const Quat< T > &

q

)

#include <opencv2/core/quaternion.hpp>

\[arctanh(q) = \frac{\ln(q + 1) - \ln(1 - q)}{2}\]

.

Parameters

q	a quaternion.

For example

Quatd q(1,2,3,4);
atanh(q);

cos()

template<typename T >

Quat< T > cv::cos

(

const Quat< T > &

q

)

#include <opencv2/core/quaternion.hpp>

\[\cos(p) = \cos(w) * \cosh(||\boldsymbol{v}||) - \sin(w)\frac{\boldsymbol{v}}{||\boldsymbol{v}||}\sinh(||\boldsymbol{v}||)\]

where \(\boldsymbol{v} = [x, y, z].\)

Parameters

q	a quaternion.

For example

Quatd q(1,2,3,4);
cos(q);

cosh()

template<typename T >

Quat< T > cv::cosh

(

const Quat< T > &

q

)

#include <opencv2/core/quaternion.hpp>

\[\cosh(p) = \cosh(w) * \cos(||\boldsymbol{v}||) + \sinh(w)\frac{\boldsymbol{v}}{||\boldsymbol{v}||}\sin(||\boldsymbol{v}||)\]

where \(\boldsymbol{v} = [x, y, z].\)

Parameters

q	a quaternion.

For example

Quatd q(1,2,3,4);
cosh(q);

crossProduct()

template<typename T >

Quat< T > cv::crossProduct	(	const Quat< T > &	p,
		const Quat< T > &	q )

#include <opencv2/core/quaternion.hpp>

\[p \times q = \frac{pq- qp}{2}\]

\[p \times q = \boldsymbol{u} \times \boldsymbol{v}\]

\[p \times q = (cz-dy)i + (dx-bz)j + (by-xc)k \]

For example

Quatd q{1,2,3,4};
Quatd p{5,6,7,8};
crossProduct(p, q);

exp()

template<typename T >

Quat< T > cv::exp

(

const Quat< T > &

q

)

Python:
	cv.exp(	src[, dst]	) ->	dst

#include <opencv2/core/quaternion.hpp>

\[\exp(q) = e^w (\cos||\boldsymbol{v}||+ \frac{v}{||\boldsymbol{v}||})\sin||\boldsymbol{v}||\]

where \(\boldsymbol{v} = [x, y, z].\)

Parameters

q	a quaternion.

For example:

Quatd q{1,2,3,4};
cout << exp(q) << endl;

inv()

template<typename T >

Quat< T > cv::inv	(	const Quat< T > &	q,
		QuatAssumeType	assumeUnit = QUAT_ASSUME_NOT_UNIT )

#include <opencv2/core/quaternion.hpp>

Parameters

q	a quaternion.
assumeUnit	if QUAT_ASSUME_UNIT, quaternion q assume to be a unit quaternion and this function will save some computations.

For example

Quatd q(1,2,3,4);
inv(q);
 
QuatAssumeType assumeUnit = QUAT_ASSUME_UNIT;
q = q.normalize();
inv(q, assumeUnit);//This assumeUnit means p is a unit quaternion

log()

template<typename T >

Quat< T > cv::log	(	const Quat< T > &	q,
		QuatAssumeType	assumeUnit = QUAT_ASSUME_NOT_UNIT )

Python:
	cv.log(	src[, dst]	) ->	dst

#include <opencv2/core/quaternion.hpp>

\[\ln(q) = \ln||q|| + \frac{\boldsymbol{v}}{||\boldsymbol{v}||}\arccos\frac{w}{||q||}.\]

where \(\boldsymbol{v} = [x, y, z].\)

Parameters

q	a quaternion.
assumeUnit	if QUAT_ASSUME_UNIT, q assume to be a unit quaternion and this function will save some computations.

For example

Quatd q1{1,2,3,4};
cout << log(q1) << endl;

operator*() [1/2]

template<typename T >

Quat< T > cv::operator*	(	const Quat< T > &	,
		const T	)

#include <opencv2/core/quaternion.hpp>

operator*() [2/2]

template<typename T >

Quat< T > cv::operator*	(	const T	,
		const Quat< T > &	)

#include <opencv2/core/quaternion.hpp>

operator<<() [1/3]

template<typename _Tp >

std::ostream & cv::operator<<	(	std::ostream &	,
		const DualQuat< _Tp > &	)

#include <opencv2/core/dualquaternion.hpp>

operator<<() [2/3]

template<typename _Tp >

std::ostream & cv::operator<<	(	std::ostream &	,
		const Quat< _Tp > &	)

#include <opencv2/core/quaternion.hpp>

operator<<() [3/3]

template<typename S >

std::ostream & cv::operator<<	(	std::ostream &	,
		const Quat< S > &	)

#include <opencv2/core/quaternion.hpp>

power() [1/2]

template<typename T >

Quat< T > cv::power	(	const Quat< T > &	q,
		const Quat< T > &	p,
		QuatAssumeType	assumeUnit = QUAT_ASSUME_NOT_UNIT )

#include <opencv2/core/quaternion.hpp>

\[p^q = e^{q\ln(p)}.\]

Parameters

p	base quaternion of power function.
q	index quaternion of power function.
assumeUnit	if QUAT_ASSUME_UNIT, quaternion \(p\) assume to be a unit quaternion and this function will save some computations.

For example

Quatd p(1,2,3,4);
Quatd q(5,6,7,8);
power(p, q);
 
QuatAssumeType assumeUnit = QUAT_ASSUME_UNIT;
p = p.normalize();
power(p, q, assumeUnit); //This assumeUnit means p is a unit quaternion

power() [2/2]

template<typename T >

Quat< T > cv::power	(	const Quat< T > &	q,
		const T	x,
		QuatAssumeType	assumeUnit = QUAT_ASSUME_NOT_UNIT )

#include <opencv2/core/quaternion.hpp>

\[q^x = ||q||(cos(x\theta) + \boldsymbol{u}sin(x\theta))).\]

Parameters

q	a quaternion.
x	index of exponentiation.
assumeUnit	if QUAT_ASSUME_UNIT, quaternion q assume to be a unit quaternion and this function will save some computations.

For example

Quatd q(1,2,3,4);
power(q, 2.0);
 
QuatAssumeType assumeUnit = QUAT_ASSUME_UNIT;
double angle = CV_PI;
Vec3d axis{0, 0, 1};
Quatd q1 = Quatd::createFromAngleAxis(angle, axis); //generate a unit quat by axis and angle
power(q1, 2.0, assumeUnit);//This assumeUnit means q1 is a unit quaternion.

Note

the type of the index should be the same as the quaternion.

sin()

template<typename T >

Quat< T > cv::sin

(

const Quat< T > &

q

)

#include <opencv2/core/quaternion.hpp>

\[\sin(p) = \sin(w) * \cosh(||\boldsymbol{v}||) + \cos(w)\frac{\boldsymbol{v}}{||\boldsymbol{v}||}\sinh(||\boldsymbol{v}||)\]

where \(\boldsymbol{v} = [x, y, z].\)

Parameters

q	a quaternion.

For example

Quatd q(1,2,3,4);
sin(q);

sinh()

template<typename T >

Quat< T > cv::sinh

(

const Quat< T > &

q

)

#include <opencv2/core/quaternion.hpp>

\[\sinh(p) = \sin(w)\cos(||\boldsymbol{v}||) + \cosh(w)\frac{v}{||\boldsymbol{v}||}\sin||\boldsymbol{v}||\]

where \(\boldsymbol{v} = [x, y, z].\)

Parameters

q	a quaternion.

For example

Quatd q(1,2,3,4);
sinh(q);

sqrt()

template<typename S >

Quat< S > cv::sqrt	(	const Quat< S > &	q,
		QuatAssumeType	assumeUnit = QUAT_ASSUME_NOT_UNIT )

Python:
	cv.sqrt(	src[, dst]	) ->	dst

#include <opencv2/core/quaternion.hpp>

tan()

template<typename T >

Quat< T > cv::tan

(

const Quat< T > &

q

)

#include <opencv2/core/quaternion.hpp>

\[\tan(q) = \frac{\sin(q)}{\cos(q)}.\]

Parameters

q	a quaternion.

For example

Quatd q(1,2,3,4);
tan(q);

tanh()

template<typename T >

Quat< T > cv::tanh

(

const Quat< T > &

q

)

#include <opencv2/core/quaternion.hpp>

\[ \tanh(q) = \frac{\sinh(q)}{\cosh(q)}.\]

Parameters

q	a quaternion.

For example

Quatd q(1,2,3,4);
tanh(q);

See also

sinh, cosh