Struct Quaternion 

pub struct Quaternion {
    pub w: f32,
    pub x: f32,
    pub y: f32,
    pub z: f32,
}

The four components of a rotation quaternion, Hamilton convention, by name.

Named rather than an array because the order of four numbers is the one convention no type can check: PX4’s q[4] and ArduPilot’s Quaternion put the scalar first, while ROS, Eigen, glam’s to_array and nalgebra’s coords and From<[f32; 4]> put it last. A quaternion read in the other order is still a finite unit quaternion, and rotates the wrong way. So there is no conversion from an array and no positional constructor: a caller writes Quaternion { w: q.w, x: q.i, y: q.j, z: q.k } from nalgebra, or { w: q[0], x: q[1], .. } from PX4, and the order is on the page.

It carries no frames; Attitude’s constructors say which rotation it is.

Fields

w: f32

The scalar part, cos(θ/2).

x: f32

The first vector component, sin(θ/2) times the axis’s first.

y: f32

The second vector component.

z: f32

The third vector component.

Implementations

impl Quaternion

pub const IDENTITY: Self

No rotation.

Trait Implementations

impl Clone for Quaternion

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Quaternion

impl Debug for Quaternion

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Format for Quaternion

Available on crate feature defmt only.

fn format(&self, f: Formatter<'_>)

Writes the defmt representation of self to fmt.

impl PartialEq for Quaternion

fn eq(&self, other: &Self) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Quaternion