he signal.)
See the related function <tt>fft</tt> which supplies a default axis and
handedness.
</p>
<p>
The transform axis, <tt>A</tt> must be a pure quaternion (real or
complex) but it need not have unit modulus (although the transform itself
is computed using a unit-modulus axis, so that the axis is a root of -1).
</p>
<p>
This function uses the MATLAB&reg; <tt>fft</tt> function to compute two
or four complex inverse FFTs depending on whether <tt>X</tt> is real or complex.
If either or both are complex, 