George,
Running the below code:
*#include <iostream>#include <gnuradio/filter/firdes.h>using namespace
std;int main() { cout << "!!!Hello World!!!" << endl; // prints !!!Hello
World!!! std::vector<float> taps = gr::filter::firdes::low_pass(1, 1, 0.3,
0.1); for(int i = 0; i < taps.size(); i++) cout << "tap " << i << ":" <<
"\t" << taps[i] << "\n"; return 0;}*
*I get the output:*
!!!Hello World!!!
tap 0: -0.00124749
tap 1: 0.0026334
tap 2: -3.313e-18
tap 3: -0.00722382
tap 4: 0.00725102
tap 5: 0.0112526
tap 6: -0.0272494
tap 7: 1.54168e-17
tap 8: 0.0582835
tap 9: -0.0539706
tap 10: -0.0877955
tap 11: 0.298026
tap 12: 0.600081
tap 13: 0.298026
tap 14: -0.0877955
tap 15: -0.0539706
tap 16: 0.0582835
tap 17: 1.54168e-17
tap 18: -0.0272494
tap 19: 0.0112526
tap 20: 0.00725102
tap 21: -0.00722382
tap 22: -3.313e-18
tap 23: 0.0026334
tap 24: -0.00124749
śr., 23 lut 2022 o 02:39 George Edwards <gedwards....@gmail.com> napisał(a):
> Hi Marcin and Vasil,
>
> Thank you guys very much!
>
> Marcin: I did as you suggested and left out win_type and beta.
> Vasil: Based on the conversation exchanges between you Marcin, I followed
> your suggestion to link in the gnuradio-filter library - in
> lib/CMakeLists.txt in target_link_libraries() by adding gnuradio-filter.
> Thus, the target_link_libraries in the original OOT lib/CMakeLists.txt
> file was:
> target_link_libraries(gnuradio-ge_filters gnuradio::gnuradio-runtime)
> and I added to it as shown below:
> target_link_libraries(gnuradio-ge_filters gnuradio::gnuradio-runtime
> gnuradio-filter)
> The OOT program compiles and makes the intended Gnuradio block for me to
> load in a GRC flowgraph. For experimental purposes, I made the OOT block to
> output the filter coefficients. When I run the grc, the lowpass filter
> outputs all zeros, so something is wrong!
> Marcin: You had written a piece of code to print "Hello World". Please run
> your code to print out the returned filter coefficients and let me know if
> it works well because mine is having some problems.
>
> This is how I invoked the filter method (all parameters are defined):
> vector <float> lpfilter; //vector variable will contain the filter
> coeff's
> lpfilter = gr::filter::firdes::low_pass(gain, sampling_freq, cutoff_freq,
> transition_bandwidth);
>
> Thank you guys!
>
> George
>
>
> On Tue, Feb 22, 2022 at 3:41 PM Marcin Puchlik <m.puch...@is-wireless.com>
> wrote:
>
>> Geroge,
>> I posted the working code a few messages ago. Try to check this out. BTW
>> as far as I can see those two arguments are optional (window type and
>> beta). Try to run your code without them and check if it works.
>>
>>
>> wt., 22 lut 2022 o 19:25 George Edwards <gedwards....@gmail.com>
>> napisał(a):
>>
>>> 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
>>>>
>>>
