mple, if wisdom is not available
one may wish to allocate new arrays for planning so that user data is
not overwritten.

</li></ul>

<a name="Algorithm_002drestriction-flags"></a>
<h4 class="subsubheading">Algorithm-restriction flags</h4>
<ul>
<li> <a name="index-FFTW_005fDESTROY_005fINPUT"></a>
<code>FFTW_DESTROY_INPUT</code> specifies that an out-of-place transform is
allowed to <em>overwrite its input</em> array with arbitrary data; this
can sometimes allow more efficient algorithms to be employed.
<a na