real_fft


This routine performs a forward or backward Fast Fourier Transformation on its argument data.


Location in HEALPix directory tree: src/f90/mod/healpix_fft.F90 or src/f90/mod/healpix_fftw.F90 (module healpix_fft in either case)


FORMAT

call real_fft( data, backward )


ARGUMENTS

name & dimensionality kind in/out description
       
data(:) XXX INOUT array containing the input and output data. Can be of type real(sp) or real(dp)
backward LGT IN Optional argument. If present and true, perform backward transformation, else forward


EXAMPLE:

use healpix_fft
call real_fft (data, backward=.true.)

Performs a backward FFT on data.


RELATED ROUTINES

This section lists the routines related to real_fft


complex_fft
routine for FFT of complex data

Eric Hivon 2005-08-31