Output model from Python to C/C++ in if/else format

[sami043]

Is there any built in method to export the model to .c/.cpp in if/else format? I could potentially parse the text model but that may be a little more prone to error. I saw on here someone had created a python script to do it for binary but for multiclaas it requires modifications. Specifically, what does a decision type of '2' represent?

[guolinke]

We have this feature.
refer to our test here: https://github.com/Microsoft/LightGBM/tree/master/tests/cpp_test

BTW, the decision_type = 2 is out of date now. maybe you need to retrain your model with the latest code.

@wxchan can you add more documents for the if-else conversion ?

[sami043]

I just built the latest lightGBM yesterday so that's strange that I am getting that decision type. With save_model?

[guolinke]

@sami043 It is updated today (f2bec2b). decision_type is still there, but its value range is changed.
if you model file has num_cat field, it is up to date.

[wxchan]

@sami043 you can add convert_model=SOME_PATH and convert_model_language=cpp to params , 1st is output address and 2nd is output language(now c++ is only option). And you need to re-compile c++ and python to make it work.

I actually never tried it from python. You can take a try.

@guolinke I will write some docs maybe tomorrow.

[sami043]

@wxchan, params = { 'task': 'train', 'convert_model_language': 'cpp', 'convert_model': 'C:\Some\Path\' } did not yield any outputs. @guolinke just updated to latest. I have num_cat but decision_type = 2 is still present.

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On Wed, Aug 2, 2017 at 10:38 AM, wxchan ***@***.***> wrote: @sami043 <https://github.com/sami043> you can add convert_model=SOME_PATH and convert_model_language=cpp to params , 1st is output address and 2nd is output language(now c++ is only option). And you need to re-compile c++ and python to make it work. I actually never tried it from python. You can take a try. @guolinke <https://github.com/guolinke> I will write some docs maybe tomorrow. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#769 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AdPb5hM6rmIOd5yt7TBOjx3XSUG8mPX_ks5sUJgNgaJpZM4OrNXX> .

[wxchan]

@sami043 sorry, I forgot. It is only implemented in command line version now.

[sami043]

@wxchan

Thanks for the quick replies.

Are there plans to expand it to non-command line later on? Or would it be possible to load a .txt model through the command line interface and export the .cpp code?

[wxchan]

@sami043 for 2nd one, yes, set task : convert_model, you can see #469

for 1st one, maybe in the future, I am a little busy these days.

[sami043]

That did the trick! Thanks!

[beutlgb]

Hey,
I have a model.txt file, i understand thet i can use the CLI to convert it to an if-else code. but i didnt understand exactly how to do it.
can you write the command line i need to use to convert the model.txt file.
can i do this from the pyhton interface?
Thanks very much'
Great package!!

[SoftwareApe]

Is there also a guide somewhere on how to use the converted C++ model? I can't find anything using Google.