Hi Ron,
Sorry for bothering some more!
In Debugging it appears that dst is not pointing to the input data (
input_items[0]), which we pointed to with pointer variable in at the start
of the work(...) method
(const gr_complex *in = (const gr_complex *) input_items[0];
Here is a snippet of my Debugging code and the values I see in ge_in =
dst[i] while single stepping through the code are all zeros.
gr_complex * dst; // copy from your code:
dst = ofdm_fft.get_inbuf(); //copy from your code
//****** my debug code starts **********
gr_complex ge_in;
for(int i = 0; i < 8; i++) // I am inputting 8 samples
{
ge_in = dst[i]; // extracting the values in dst shows
zero's
}
// ******my debug code ends *********
It appears that setting dst = ofdm_fft.get_inbuf() is not pointing to the
actual input samples values.
I did not see anywhere in your code where there is an explicit binding
between in and get_inbuf().
I will appreciate it if you can help me here!
Thank you!
George
On Wed, Dec 15, 2021 at 12:32 AM Ron Economos <w...@comcast.net> wrote:
> FFT support is built in to GNU Radio with FFTW. Here's how it's done.
> First, define it in your foo_impl.h file. The options are fft_complex_fwd,
> fft_complex_rev, fft_real_fwd and fft_real_rev.
>
> https://github.com/drmpeg/gr-paint/blob/master/lib/paint_bc_impl.h#L25
>
> https://github.com/drmpeg/gr-paint/blob/master/lib/paint_bc_impl.h#L41
>
> Then initialize it in your foo_impl.cc constructor.
>
> https://github.com/drmpeg/gr-paint/blob/master/lib/paint_bc_impl.cc#L47
>
> Then execute it.
>
>
> https://github.com/drmpeg/gr-paint/blob/master/lib/paint_bc_impl.cc#L175-L179
>
> You'll need to add the component in the top level CMakeLists.txt.
>
> https://github.com/drmpeg/gr-paint/blob/master/CMakeLists.txt#L78
>
> And link with it in lib/CMakeLists.txt
>
> https://github.com/drmpeg/gr-paint/blob/master/lib/CMakeLists.txt#L25
>
> If you need a window, you can look at the block implementation file for
> details.
>
> https://github.com/gnuradio/gnuradio/blob/master/gr-fft/lib/fft_v_fftw.cc
>
> Ron
> On 12/14/21 7:53 PM, George Edwards wrote:
>
> Dear GNURadio Community:
>
> I am writing a C++ OOT block where the signal processing requires
> the computation of both fft and ifft. Is there any Gnuradio C++ functions
> for the fft and ifft? If not, is there any way to wrap in Python's
> libraries with these methods into C++ OOT?
>
> Thank you!
>
> Regards,
> George
>
>
