Hello Vasil and Marcin, Thanks very much for your help.
I have all the relevant #include header files and invoke the low_pass filter as follows: lpfilter = gr::filter::firdes::low_pass(gain, sampling_freq, cutoff_freq, transition_bandwidth, fft::window::win_type::WIN_HAMMING, beta); Observations: Using the mouse to hover over WIN_HAMMING, I can see that it interprets the win_type enum variable and correctly assigns it a value of "0" (which is the value stated in the Gnuradio C++ API Reference manual). However, there is a squidly under beta. Hovering over beta, the error message is: Argument of type "double" is incompatible with parameter of type "gr::fft::window::win_type" If one of you has a working code fragment using one of the C++ Gnuradio filter methods that you can cut, paste and send in your next email I would appreciate it. Thanks for your help. George On Tue, Feb 22, 2022 at 6:15 AM Vasil Velichkov <vvvelich...@gmail.com> wrote: > Hi George, > > On 21/02/2022 18.31, George Edwards wrote: > > lpfilter = gr::filter::firdes::low_pass(gain, sampling_freq, > cutoff_freq, transition_bandwidth, > > fft::window::win_type < > https://www.gnuradio.org/doc/doxygen/classgr_1_1fft_1_1window.html#a599d7e9625d6cc77203a8b877c4911e2>window > = fft::window::win_type::WIN_HAMMING, beta = 6.76); > > > > This failed and showed a squidly across the line with > fft::window::win_type....! > > Try adding "gr::" before "fft::window" and make sure gnuradio/fft/window.h > is included. > > #include <gnuradio/fft/window.h> > > lpfilter = gr::filter::firdes::low_pass(gain, sampling_freq, > cutoff_freq, transition_bandwidth, > gr::fft::window::win_type window = > fft::window::win_type::WIN_HAMMING, beta = 6.76); > > If this does not fix it then provide the exact error you are getting. > > Regards, > Vasil >
