# Guided Tutorials - Experience **URL:** \ **Category:** GNU Radio\ **Created:** [October 20, 2014, 10:07am UTC](https://www.ruby-forum.com/t/guided-tutorials-experience/232647 "2014-10-20T10:07:37Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![addis\_a](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/c4cdca/32.png) [@addis\_a](https://www.ruby-forum.com/u/addis_a)\ **Post date:** [October 20, 2014, 10:07am UTC](https://www.ruby-forum.com/t/guided-tutorials-experience/232647/1 "2014-10-20T10:07:37Z")
Hello, I did 2 of the Guided Tutorials - Programming GNU Radio in Python and C++ and want to tell you about my experiences. First thanks for making this tutorials! They really help me to get a good start with GNU Radio. Tutorial with Python: Since I don t have any programming experience in Pyton (and C++) I really liked it that it is very detailed! Could do it and understand everything! Tutorial with C++: Really had problems doing this tutorial. I must admit that my C++ knowledge is very low. - In the tutorial there is just written to edit the and how to edit the .cc file. But in the header there are also things to be edited. - After declaring the function get\_minimum\_distances in header file and trying to compile (make) I get the error: unknown variable d\_gray\_code. So I guess in the .cc file there has to be done some assignment like d\_gray\_code = gray\_code ? - After doing some editings in header and .cc file I managed to compile. - To prevent any errors I copied the given (on the tutorial page) .xml code into my .xml file. After cmake …/ → make → sudo make install → sudo ldconfig → restart GRC → new block did not appear ? - Maybe it s because the last 6 lines of xml file ? There appear 2 times. After editing the file made by gr\_modtool with the instructions it worked 🙂 But after having done a QA test as it is written on the tutorial I get wrong results (AssertError). Seems that although I call qpsk = tutorial.my\_qpsk\_demod\_cb(gray\_code) with gray\_code = false The code just enters the if clause with gray\_code == true? Do you have any idea why? Here are my files, which are nearly the same as the ones in examples. [https://dl.dropboxusercontent.com/u/33858807/my\_qpsk\_demod\_cb\_impl.cc](https://dl.dropboxusercontent.com/u/33858807/my_qpsk_demod_cb_impl.cc) [https://dl.dropboxusercontent.com/u/33858807/my\_qpsk\_demod\_cb\_impl.h](https://dl.dropboxusercontent.com/u/33858807/my_qpsk_demod_cb_impl.h) [https://dl.dropboxusercontent.com/u/33858807/qa\_my\_qpsk\_demod\_cb.py](https://dl.dropboxusercontent.com/u/33858807/qa_my_qpsk_demod_cb.py) Thank you in advance! Best regards, Vlad ---
**Author:** ![Vlad\_Stoica](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/58f4c7/32.png) [@Vlad\_Stoica](https://www.ruby-forum.com/u/Vlad_Stoica)\ **Post date:** [October 20, 2014, 1:39pm UTC](https://www.ruby-forum.com/t/guided-tutorials-experience/232647/2 "2014-10-20T13:39:26Z")
Vlad, thanks for going through the guided tutorials, and thanks for your feedback. We’ll address those soon and fix the tutorials. As for your solution, I’m not sure. I recommend putting a couple of print statements so you can tell what’s going on. cheers, M ---
**Author:** ![Vlad\_Stoica](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/58f4c7/32.png) [@Vlad\_Stoica](https://www.ruby-forum.com/u/Vlad_Stoica)\ **Post date:** [October 22, 2014, 11:33am UTC](https://www.ruby-forum.com/t/guided-tutorials-experience/232647/3 "2014-10-22T11:33:09Z")
On 20.10.2014 13:37, Martin B. wrote: > Hello Martin, thank you for the hint! After printing the variable, I noticed I assigned a variable wrongly. However, now everything works fine 🙂 If there is someone else who has problems doing this tutorial, here is the code : [https://dl.dropboxusercontent.com/u/33858807/GNURadio/my\_qpsk\_demod\_2\_cb\_impl.cc](https://dl.dropboxusercontent.com/u/33858807/GNURadio/my_qpsk_demod_2_cb_impl.cc) [https://dl.dropboxusercontent.com/u/33858807/GNURadio/my\_qpsk\_demod\_2\_cb\_impl.h](https://dl.dropboxusercontent.com/u/33858807/GNURadio/my_qpsk_demod_2_cb_impl.h) [https://dl.dropboxusercontent.com/u/33858807/GNURadio/qa\_my\_qpsk\_demod\_2\_cb.py](https://dl.dropboxusercontent.com/u/33858807/GNURadio/qa_my_qpsk_demod_2_cb.py) [https://dl.dropboxusercontent.com/u/33858807/GNURadio/tutorial\_my\_qpsk\_demod\_2\_cb.xml](https://dl.dropboxusercontent.com/u/33858807/GNURadio/tutorial_my_qpsk_demod_2_cb.xml) Best regards, Vlad ---
**Author:** ![Vlad\_Stoica](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/58f4c7/32.png) [@Vlad\_Stoica](https://www.ruby-forum.com/u/Vlad_Stoica)\ **Post date:** [October 22, 2014, 11:39am UTC](https://www.ruby-forum.com/t/guided-tutorials-experience/232647/4 "2014-10-22T11:39:06Z")
On 10/22/2014 11:26 AM, Vlad Stoica wrote: > thank you for the hint! After printing the variable, I noticed I > assigned a variable wrongly. > > However, now everything works fine 🙂 > > If there is someone else who has problems doing this tutorial, here is > the code : I would like to point out that we _do_ provide the ‘solutions’ in a dedicated repo: > **[GitHub - gnuradio/gr-tutorial: A tutorial OOT module for GNU Radio](https://github.com/gnuradio/gr-tutorial)** > > A tutorial OOT module for GNU Radio Cheers, M ---
**Author:** ![Vlad\_Stoica](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/v/58f4c7/32.png) [@Vlad\_Stoica](https://www.ruby-forum.com/u/Vlad_Stoica)\ **Post date:** [October 22, 2014, 12:16pm UTC](https://www.ruby-forum.com/t/guided-tutorials-experience/232647/5 "2014-10-22T12:16:36Z")
> I would like to point out that we _do_ provide the ‘solutions’ in a > dedicated repo: > > [GitHub - gnuradio/gr-tutorial: A tutorial OOT module for GNU Radio · GitHub](https://github.com/gnuradio/gr-tutorial) > > Cheers, > M Oops, sorry! I somehow missed that…