Thread Subject: fft_ifft_conj

Know that ifft(fft(x))=x

But how do I get x out of conj(fft(x))?

Many thank for your help,

Jerry DiBona
gerald-dibona@uiowa.edu

"Gerald DiBona" <gerald-dibona@uiowa.edu> wrote in message
<g37quk$etc$1@fred.mathworks.com>...
> Know that ifft(fft(x))=x
>
> But how do I get x out of conj(fft(x))?
>
> Many thank for your help,
>
> Jerry DiBona
> gerald-dibona@uiowa.edu

ifft(conj(conj(x))); % (???)

ment

ifft(conj(conj(fft(x))))

On 17 Jun, 10:00, "Gerald DiBona" <gerald-dib...@uiowa.edu> wrote:
> Know that ifft(fft(x))=x
>
> But how do I get x out of conj(fft(x))?

Homework?

To solve this, look very closely at the formulas for the
DFT and IDFT. Is it possible to compute the Inverse DFT
using only the (forward) FFT function?

The answer is 'yes' and the key to find an answer your
question is to find out how one can do that.

Rune

Hi Rune!
But why not very simple

ifft(conj(conj(fft([1 2 3 4])))) % ???

Lars

On 18 Jun, 18:39, "Lars " <mustermann.klaus.TO.REM...@gmx.de> wrote:
> Hi Rune!
> But why not very simple
>
> ifft(conj(conj(fft([1 2 3 4])))) % ???

Because if the question is a homework question, the
OP will be supposed to figure that out for himself.

Rune