 that the output data be stored in an FFTW-defined
&ldquo;scrambled&rdquo; format.  (In particular, this is the analogue of
transposed output in the multidimensional case: scrambled output saves
a communications step.)  If you pass <code>FFTW_MPI_SCRAMBLED_OUT</code> in
the flags, then the output is stored in this (undocumented) scrambled
order.  Conversely, to perform the inverse transform of data in
scrambled order, pass the <code>FFTW_MPI_SCRAMBLED_IN</code> flag. 
<a name="index-FFTW_005fMPI_005fSCRAMBL