>fftw_alloc</samp>&rsquo; to
ensure aligned memory for maximum performance (see <a href="Allocating-aligned-memory-in-Fortran.html#Allocating-aligned-memory-in-Fortran">Allocating aligned memory in Fortran</a>); this also makes it easy to reference the
same memory as both a real array and a complex array.
</p>
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<div class="example">
<pre class="example">  real(C_DOUBLE), pointer :: in(:,:,:)
  complex(C_DOUBLE_COMPLEX)