</code>.  As usual, the strides etcetera of
<code>rfftwnd_real_to_complex</code> or <code>rfftwnd_complex_to_real</code> are no
specified in the advanced planner routines,
<code>fftw_plan_many_dft_r2c</code> or <code>fftw_plan_many_dft_c2r</code>.
</p>
<a name="Wisdom-2"></a>
<h3 class="heading">Wisdom</h3>

<p>In FFTW 2, you had to supply the <code>FFTW_USE_WISDOM</code> flag in order to
use wisdom; in FFTW 3, wisdom is always used.  (You could simulate the
FFTW 2 wisdom-less behavior by calling <code>fftw