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Mathematics

Quaternions vs. Matrices for Representing Rotations in 3D Space

Quick fact

Quaternions require only 4 numbers to represent a rotation, while a rotation matrix needs 9—yet quaternions avoid a notorious failure mode called gimbal lock that can make Euler-angle systems freeze up.

Why this is interesting

You can rotate an object in 3D using a 3×3 matrix or a 4‑number quaternion. Both do the same job, so why do animators and spacecraft engineers ditch matrices for quaternions?