Quaternion operators i, j and k
qi/qj/qk
These three functions return constant quaternions with values corresponding to the three quaternion operators i, j and k.
The symbol i is a builtin MATLAB® operator for the complex root of -1, and therefore it cannot be used for the quaternion i. This is why the notation qi is used.
>> qi + qj + qk ans = 1 * I + 1 * J + 1 * K