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FFT wierdness in WAVE [message #6088]

Wed, 27 March 1996 00:00

howie
Messages: 5
Registered: May 1994

Junior Member

Can anyone here enlighten me on why the plots produced with the
following commands are so different?

Other vector lengths which produce this strange behavior are;

5788 5788+16 5788+48
9848 9848-16 9848-32
and others

> plot,abs(fft(findgen(8395),-1)) - works!
> plot,abs(fft(findgen(8396),-1)) - fails! Peaks where none should be.

The contents of the vector do not matter. When the vector length is
8396 you get a spike on top of the proper spectrum.

Any ideas?

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FFT wierdness in WAVE

By: howie on Wed, 27 March 1996 00:00

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