Re: [Discuss-gnuradio] How to make an FFT block in c++

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You're right; the following syntax is the least ambiguous for creating Blackmanharris windows in c++:

const std::vector< float >  fft_window = gr::filter::firdes::window(gr::filter::firdes::WIN_BLACKMAN_HARRIS, 1024, NULL);

Sincerely,

Tommy James Tracy II

Ph.D Student

High Performance Low Power Lab

University of Virginia

Phone: 913-775-2241

On Nov 1, 2013, at 6:04 AM, Alexandru Csete <oz9aec@gmail.com> wrote:

On Fri, Nov 1, 2013 at 6:16 AM, Tommy Tracy II <tjt7a@virginia.edu> wrote:

Thanks a lot. I do have a question about the 6.67 that you pass to the
gr::firdes::window(gr::filter::firdes::WIN_BLACKMAN_HARRIS, SIZE, 6.67);

What is the importance of this value? Is this the default BETA? I found that
when creating a BLACKMANHARRIS window in python and c++, I got two different
results.

If I recall correctly that parameter is only used for the Kaiser
window and not for the others.

Alex