You could probably cut and paste the high level main code showing how you
are generating the sine wave, how you are calling the rfft( ) and how you
are calculating the magnitude.  Then perhaps myself (and others) will be
able to help you, but I can't commit to debugging your project for you via
this newsgroup.

-Shawn


"Eugene" <johnbesel@web.de> wrote in message
news:6484110f.0412170527.75cdf065@posting.google.com...
> hello Shawn Steenhagen,
> I thank you for your answer.
>
> I've done so you said me.
> I took the magnitude of the result of rfft().
>
> then I plotted it in ccs, but I haven't got the expected result. I
> expected to see only one peak, that correspond to the frequency of the
> sine.
>
> And if I take a rectangle input, then I don't see Harmonic waves and
> any peaks.
>
> I would like to sent you my quellcode or show you it somehow. It can
> be possible, that I write only one Line false, and that make my plott
> fals.
>
> can I upload my project somewhere on this site or like attachment in
> my message?
>
> thank you.

hello Shawn Steenhagen,
I thank you for your answer.

I've done so you said me. 
I took the magnitude of the result of rfft().

then I plotted it in ccs, but I haven't got the expected result. I
expected to see only one peak, that correspond to the frequency of the
sine.

And if I take a rectangle input, then I don't see Harmonic waves and
any peaks.

I would like to sent you my quellcode or show you it somehow. It can
be possible, that I write only one Line false, and that make my plott
fals.

can I upload my project somewhere on this site or like attachment in
my message?

thank you.