Calculate conjugate of quaternion
n = quatconj(q)
n = quatconj(q) calculates the conjugate, n, for a given quaternion, q. Input q is an m-by-4 matrix containing m quaternions. n returns an m-by-4 matrix of conjugates. Each element of q must be a real number. Additionally, q has its scalar number as the first column.
The quaternion has the form of
The quaternion conjugate has the form of
 Stevens, Brian L., Frank L. Lewis, Aircraft Control and Simulation, Wiley–Interscience, 2nd Edition.