I'm running into a strange issue while trying to perform an FFT on a 4PAM modulated signal sampled at 100KHz with a symbol duration of 100 samples.

u_t_4PAM = <1x100000 double>

Relevant code:
fft_4PAM = ftt(u_t_4PAM,length(u_t_4PAM))/length(u_t_4PAM)

??? Undefined function or method 'ftt' for input arguments of type 'double'.

Eric wrote:
....

> Relevant code:
> fft_4PAM = ftt(u_t_4PAM,length(u_t_4PAM))/length(u_t_4PAM)
> 
> ??? Undefined function or method 'ftt' for input arguments of type 
> 'double'.

What do

which fft
whos fft

return?

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"Eric " <eric.williams.neu+matlabcentral@gmail.notthis.com> wrote in message <ib1i2b$kub$1@fred.mathworks.com>...
> I'm running into a strange issue while trying to perform an FFT on a 4PAM modulated signal sampled at 100KHz with a symbol duration of 100 samples.
> 
> u_t_4PAM = <1x100000 double>
> 
> Relevant code:
> fft_4PAM = ftt(u_t_4PAM,length(u_t_4PAM))/length(u_t_4PAM)
> 
> ??? Undefined function or method 'ftt' for input arguments of type 'double'.

There is only one among eight is good
TFF, FTT, FTF, FFT, TFT, TTF, FFF, TTT

Bruno 

"Bruno Luong" <b.luong@fogale.findmycountry> wrote in message <ib1ims$3r0$1@fred.mathworks.com>...
> "Eric " <eric.williams.neu+matlabcentral@gmail.notthis.com> wrote in message <ib1i2b$kub$1@fred.mathworks.com>...
> > I'm running into a strange issue while trying to perform an FFT on a 4PAM modulated signal sampled at 100KHz with a symbol duration of 100 samples.
> > 
> > u_t_4PAM = <1x100000 double>
> > 
> > Relevant code:
> > fft_4PAM = ftt(u_t_4PAM,length(u_t_4PAM))/length(u_t_4PAM)
> > 
> > ??? Undefined function or method 'ftt' for input arguments of type 'double'.
> 
> There is only one among eight is good
> TFF, FTT, FTF, FFT, TFT, TTF, FFF, TTT
> 
> Bruno 

Thank you so much Bruno. I need to leave my lab immediately. It's obviously just time to give up for the day :-).

Eric wrote:
....

>> > fft_4PAM = ftt(u_t_4PAM,length(u_t_4PAM))/length(u_t_4PAM)
>> > > ??? Undefined function or method 'ftt' for input arguments of type 
>> 'double'.
>>
>> There is only one among eight is good
>> TFF, FTT, FTF, FFT, TFT, TTF, FFF, TTT
>>
>> Bruno 
> 
> Thank you so much Bruno. I need to leave my lab immediately. It's 
> obviously just time to give up for the day :-).

And I missed it, too, ...  :(

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