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# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
# AIFTXR -- Inverse fourier transform (complex transform, real arrays).
# The inverse transform of the real arrays FR and FI containing complex data
# pairs is computed and the complex spatial data coefficients are returned in
# the real arrays SR and SI. The transformation may be performed in place if
# desired. NPIX must be a power of 2.
procedure aiftxr (fr, fi, sr, si, npix)
real fr[ARB], fi[ARB] # transform, frequency domain (input)
real sr[ARB], si[ARB] # data, spatial domain (output)
int npix
int ier
begin
# The following are no-ops if the transform is being performed
# in place.
call amovr (fr, sr, npix)
call amovr (fi, si, npix)
# Compute the inverse transform.
call fft842 (1, npix, sr, si, ier)
if (ier == 1)
call fatal (1, "afftxr: npix not a power of 2")
end
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