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jvs:fscan:manual:chapter2:expression:fft

fScan Reference Manual, Chapter 2 (CmdLineOptions:Expr): fft

fft -- Perform a fast Fourier transform

usage: -expr fft flag [outwdsiz]

The FFT expression performs a fast Fourier transform (FFT) on an entire data set.
The FLAG argument controls options as:

FLAG:

  • 1 - frequency space to image space (default: image to frequency)1-dimensional FFT
  • 2 - 2-dimensional FFT (default: 1-dimensional FFT)
  • 4 - input has phase (default: magnitude only, set phase to 0)
  • 8 - output is complex (default: single value, magnitude only)
  • 16 - output is phase only
  • 32 - output is real only
  • 48 - output is imaginary only
  • 64 - magnitude and phase are highest dimension (default: lowest dimension)

OUTWDSIZ is the output word size. The default is float32 if FLAG indicates single values ((FLAG&56)!=8), or cpx_float32 if (FLAG&56)==8.

See Also:
fScan Home,
fScan Manual,
CmdLineOptions,
Expression Command,
Manual Help

jvs/fscan/manual/chapter2/expression/fft.txt · Last modified: 2014/08/04 16:03 (external edit)