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Re: Why does the default fft data number change for a identification data
Posted:
Apr 4, 2013 3:11 PM


On Thu, 04 Apr 2013 09:46:14 0700, fl wrote: > I try to run a snippnet of identification toolbox user guide: > > % Load input u2 and output y2 load dryer2; > % Create iddata object tdata = iddata(y2,u2,0.08); > % Take the Fourier transform of the data % transforming it to frequency > domain fdata = fft(tdata) > % Get property values of data get(fdata) > > The length of tdata is 1000 while the length of fdata is 501. I have > check function fft and I do not find anything can explain it to me. > Could you help me on this question?
What did you notice about workspace arrays when you copied, pasted, and ran one of the example programs in the section "Help > Matlab > Mathematics > Fourier Analysis and Filtering"?
> Thanks,
for what?



