frc::Quaternion Class Reference

Represents a quaternion. More...

#include <frc/geometry/Quaternion.h>

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

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

Detailed Description

Represents a quaternion.

Constructor & Destructor Documentation

Quaternion() [1/2]

frc::Quaternion::Quaternion ( )

constexprdefault

Constructs a quaternion with a default angle of 0 degrees.

Quaternion() [2/2]

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

inlineconstexpr

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

inlineconstexpr

Returns the conjugate of the quaternion.

Dot()

double frc::Quaternion::Dot ( const Quaternion & other ) const

inlineconstexpr

Returns the elementwise product of two quaternions.

Exp() [1/2]

Quaternion frc::Quaternion::Exp ( ) const

inlineconstexpr

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

inlineconstexpr

Matrix exponential of a quaternion.

Parameters

other

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

FromRotationVector()

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

inlinestaticconstexpr

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

inlineconstexpr

Returns the inverse of the quaternion.

Log() [1/2]

Quaternion frc::Quaternion::Log ( ) const

inlineconstexpr

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

inlineconstexpr

Log operator of a quaternion.

Parameters

other

The quaternion to map this quaternion onto

Norm()

double frc::Quaternion::Norm ( ) const

inlineconstexpr

Calculates the L2 norm of the quaternion.

Normalize()

Quaternion frc::Quaternion::Normalize ( ) const

inlineconstexpr

Normalizes the quaternion.

operator*() [1/2]

Quaternion frc::Quaternion::operator* ( const Quaternion & other ) const

inlineconstexpr

Multiply with another quaternion.

Parameters

other

The other quaternion.

operator*() [2/2]

Quaternion frc::Quaternion::operator* ( double other ) const

inlineconstexpr

Multiples with a scalar value.

Parameters

other

the scalar value

operator+()

Quaternion frc::Quaternion::operator+ ( const Quaternion & other ) const

inlineconstexpr

Adds with another quaternion.

Parameters

other

the other quaternion

operator-()

Quaternion frc::Quaternion::operator- ( const Quaternion & other ) const

inlineconstexpr

Subtracts another quaternion.

Parameters

other

the other quaternion

operator/()

Quaternion frc::Quaternion::operator/ ( double other ) const

inlineconstexpr

Divides by a scalar value.

Parameters

other

the scalar value

operator==()

bool frc::Quaternion::operator== ( const Quaternion & other ) const

inlineconstexpr

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 ( double t ) const

inlineconstexpr

Calculates this quaternion raised to a power.

Parameters

t	the power to raise this quaternion to.

ToRotationVector()

Eigen::Vector3d frc::Quaternion::ToRotationVector ( ) const

inlineconstexpr

Returns the rotation vector representation of this quaternion.

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

W()

double frc::Quaternion::W ( ) const

inlineconstexpr

Returns W component of the quaternion.

X()

double frc::Quaternion::X ( ) const

inlineconstexpr

Returns X component of the quaternion.

Y()

double frc::Quaternion::Y ( ) const

inlineconstexpr

Returns Y component of the quaternion.

Z()

double frc::Quaternion::Z ( ) const

inlineconstexpr

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