frc::Quaternion Class Reference

Represents a quaternion. More...

#include <frc/geometry/Quaternion.h>

Public Member Functions
	Quaternion ()=default
	Constructs a quaternion with a default angle of 0 degrees. More...
	Quaternion (double w, double x, double y, double z)
	Constructs a quaternion with the given components. More...
Quaternion	operator+ (const Quaternion &other) const
	Adds with another quaternion. More...
Quaternion	operator- (const Quaternion &other) const
	Subtracts another quaternion. More...
Quaternion	operator* (const double other) const
	Multiples with a scalar value. More...
Quaternion	operator/ (const double other) const
	Divides by a scalar value. More...
Quaternion	operator* (const Quaternion &other) const
	Multiply with another quaternion. More...
bool	operator== (const Quaternion &other) const
	Checks equality between this Quaternion and another object. More...
double	Dot (const Quaternion &other) const
	Returns the elementwise product of two quaternions. More...
Quaternion	Conjugate () const
	Returns the conjugate of the quaternion. More...
Quaternion	Inverse () const
	Returns the inverse of the quaternion. More...
Quaternion	Normalize () const
	Normalizes the quaternion. More...
double	Norm () const
	Calculates the L2 norm of the quaternion. More...
Quaternion	Pow (const double t) const
	Calculates this quaternion raised to a power. More...
Quaternion	Exp (const Quaternion &other) const
	Matrix exponential of a quaternion. More...
Quaternion	Exp () const
	Matrix exponential of a quaternion. More...
Quaternion	Log (const Quaternion &other) const
	Log operator of a quaternion. More...
Quaternion	Log () const
	Log operator of a quaternion. More...
double	W () const
	Returns W component of the quaternion. More...
double	X () const
	Returns X component of the quaternion. More...
double	Y () const
	Returns Y component of the quaternion. More...
double	Z () const
	Returns Z component of the quaternion. More...
Eigen::Vector3d	ToRotationVector () const
	Returns the rotation vector representation of this quaternion. More...

Static Public Member Functions
static Quaternion	FromRotationVector (const Eigen::Vector3d &rvec)
	Returns the quaternion representation of this rotation vector. More...

Detailed Description

Represents a quaternion.

Constructor & Destructor Documentation

Quaternion() [1/2]

frc::Quaternion::Quaternion ( )

default

Constructs a quaternion with a default angle of 0 degrees.

Quaternion() [2/2]

frc::Quaternion::Quaternion	(	double	w,
		double	x,
		double	y,
		double	z
	)

Constructs a quaternion with the given components.

Parameters

w	W component of the quaternion.
x	X component of the quaternion.
y	Y component of the quaternion.
z	Z component of the quaternion.

Member Function Documentation

Conjugate()

Quaternion frc::Quaternion::Conjugate

(

)

const

Returns the conjugate of the quaternion.

Dot()

double frc::Quaternion::Dot

(

const Quaternion &

other

)

const

Returns the elementwise product of two quaternions.

Exp() [1/2]

Quaternion frc::Quaternion::Exp

(

)

const

Matrix exponential of a quaternion.

source: wpimath/algorithms.md

If this quaternion is in 𝖘𝖔(3) and you are looking for an element of SO(3), use FromRotationVector

Exp() [2/2]

Quaternion frc::Quaternion::Exp

(

const Quaternion &

other

)

const

Matrix exponential of a quaternion.

Parameters

other

the "Twist" that will be applied to this quaternion.

FromRotationVector()

static Quaternion frc::Quaternion::FromRotationVector ( const Eigen::Vector3d &  rvec )

static

Returns the quaternion representation of this rotation vector.

This is also the exp operator of 𝖘𝖔(3).

source: wpimath/algorithms.md

Inverse()

Quaternion frc::Quaternion::Inverse

(

)

const

Returns the inverse of the quaternion.

Log() [1/2]

Quaternion frc::Quaternion::Log

(

)

const

Log operator of a quaternion.

source: wpimath/algorithms.md

If this quaternion is in SO(3) and you are looking for an element of 𝖘𝖔(3), use ToRotationVector

Log() [2/2]

Quaternion frc::Quaternion::Log

(

const Quaternion &

other

)

const

Log operator of a quaternion.

Parameters

other

The quaternion to map this quaternion onto

Norm()

double frc::Quaternion::Norm

(

)

const

Calculates the L2 norm of the quaternion.

Normalize()

Quaternion frc::Quaternion::Normalize

(

)

const

Normalizes the quaternion.

operator*() [1/2]

Quaternion frc::Quaternion::operator*

(

const double

other

)

const

Multiples with a scalar value.

Parameters

other

the scalar value

operator*() [2/2]

Quaternion frc::Quaternion::operator*

(

const Quaternion &

other

)

const

Multiply with another quaternion.

Parameters

other

The other quaternion.

operator+()

Quaternion frc::Quaternion::operator+

(

const Quaternion &

other

)

const

Adds with another quaternion.

Parameters

other

the other quaternion

operator-()

Quaternion frc::Quaternion::operator-

(

const Quaternion &

other

)

const

Subtracts another quaternion.

Parameters

other

the other quaternion

operator/()

Quaternion frc::Quaternion::operator/

(

const double

other

)

const

Divides by a scalar value.

Parameters

other

the scalar value

operator==()

bool frc::Quaternion::operator==

(

const Quaternion &

other

)

const

Checks equality between this Quaternion and another object.

Parameters

other

The other object.

Returns

Whether the two objects are equal.

Pow()

Quaternion frc::Quaternion::Pow

(

const double

t

)

const

Calculates this quaternion raised to a power.

Parameters

t	the power to raise this quaternion to.

ToRotationVector()

Eigen::Vector3d frc::Quaternion::ToRotationVector

(

)

const

Returns the rotation vector representation of this quaternion.

This is also the log operator of SO(3).

W()

double frc::Quaternion::W

(

)

const

Returns W component of the quaternion.

X()

double frc::Quaternion::X

(

)

const

Returns X component of the quaternion.

Y()

double frc::Quaternion::Y

(

)

const

Returns Y component of the quaternion.

Z()

double frc::Quaternion::Z

(

)

const

Returns Z component of the quaternion.

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

• frc/geometry/Quaternion.h