Crate quaternion_core

Source
Expand description

Quaternion library written in Rust.

This provides Quaternion operations and interconversion with several attitude representations as generic functions (supports f32 & f64).

§Generics

Functions implementing the QuaternionOps trait can take both Quaternion<T> and Vector3<T> as arguments. In this case, Vector3<T> is treated as a Pure Quaternion.

For example:

use quaternion_core::{Vector3, Quaternion, add};
 
// --- Vector3 --- //
let v1: Vector3<f32> = [1.0, 2.0, 3.0];
let v2: Vector3<f32> = [0.1, 0.2, 0.3];
println!("{:?}", add(v1, v2));  // <--- It's [1.1, 2.2, 3.3]
 
// --- Quaternion --- //
let q1: Quaternion<f64> = (1.0, [2.0, 3.0, 4.0]);
let q2: Quaternion<f64> = (0.1, [0.2, 0.3, 0.4]);
println!("{:?}", add(q1, q2));  // <--- It's (1.1, [2.2, 3.3, 4.4])

§Versor

Versor refers to a Quaternion representing a rotation, the norm of which is 1.

The documentation for this crate basically writes Versor instead of Unit Quaternion, but the difference in usage is not clear. Please think Versor = Unit Quaternion.

Enums§

Traits§

  • QuaternionOps
    This trait provides operations common to Quaternions and Pure Quaternions (Vector3).

Functions§

  • add
    Addition of two quaternions (or vectors): a + b
  • conj
    Calculate the conjugate of Quaternion.
  • cross
    Cross product of two quaternions (or vectors): a × b
  • dot
    Dot product of two quaternions (or vectors): a · b
  • exp
    Exponential function of Quaternion or Pure Quaternion (Vector3).
  • frame_rotation
    Frame rotation by quaternion (Frame Rotation - Point Fixed)
  • from_axis_angle
    Generate Versor by specifying rotation angle[rad] and axis vector.
  • from_dcm
    Convert a DCM to a Versor representing the q v q* rotation (Point Rotation - Frame Fixed).
  • from_euler_angles
    Convert euler angles to versor.
  • from_rotation_vector
    Convert Rotation vector to Versor.
  • hadamard
    Calculate the element-wise product of two quaternions (or vectors)
  • hadamard_add
    Hadamard product and addition in one step.
  • identity
    Generate identity quaternion.
  • inv
    Calculate the inverse of Quaternion or Pure Quaternion (Vector3).
  • lerp
    Lerp (Linear interpolation)
  • ln
    Natural logarithm of Quaternion.
  • ln_versor
    Natural logarithm of Versor.
  • matrix_product
    Product of DCM and Vector3
  • mul
    Multiplication of two quaternions (or vectors).
  • negate
    Invert the sign of a Vector3 or Quaternion.
  • norm
    Calculate L2 norm of Vector3 or Quaternion.
  • normalize
    Normalization of Vector3 or Quaternion.
  • point_rotation
    Point rotation by quaternion (Point Rotation - Frame Fixed)
  • pow
    Power function of Quaternion.
  • pow_versor
    Power function of Versor.
  • rotate_a_to_b
    Calculate the versor to rotate from vector a to vector b (Without singularity!).
  • rotate_a_to_b_shortest
    Calculate the versor to rotate from vector a to vector b by the shortest path.
  • scale
    Multiplies each component of the quaternion (or vector) by a given real number, scaling the entire quaternion uniformly: s * a.
  • scale_add
    Scaling and addition in one step: s * a + b
  • slerp
    Slerp (Spherical linear interpolation)
  • sqrt
    Square root of Quaternion.
  • sqrt_versor
    Square root of Versor.
  • sub
    Subtraction of two quaternions (or vectors): a - b
  • sum
    Calculate the sum of each element of a quaternion (or vector).
  • to_axis_angle
    Calculate the rotation axis (unit vector) and the rotation angle[rad] around the axis from the Versor.
  • to_dcm
    Convert a Versor to a DCM representing the q v q* rotation (Point Rotation - Frame Fixed).
  • to_euler_angles
    Convert versor to euler angles.
  • to_rotation_vector
    Convert Versor to Rotation vector.

Type Aliases§