Re: wrapping vector<vector<double> > using boost::python

From: rwgk_at_[hidden]
Date: 2001-08-27 21:06:28

I have added a new example "nested.cpp" to the CVS tree:
http://cvs.sourceforge.net/cgi-
bin/viewcvs.cgi/boost/boost/libs/python/example/
This should answer your question.
Ralf

--- In boost_at_y..., elaine_y_at_y... wrote:
> Hi,
> 
> I have the basic functionality of creating an empty vector and being
> able to pass the vectors from c++ to python. Now, I want to be able
> to do it the other way. I'm having trouble fleshing out
> 
> matrix_double_wrapper::matrix_double_wrapper(PyObject* self, 
> python::tuple tuple)
>         : std::vector< std::vector<double> >(tuple.size())
>     {
>         std::vector< std::vector<double> >::iterator vd = begin();
>         for (int i = 0; i < tuple.size(); i++) {
>             std::vector<double> vrow;
>             // what to do next?
>             // tuple[i].get() gives me a reference
>             // how can I convert that reference to a tuple?
>             // then, I could parse that tuple to create a
>             // vector I could add to my row vector.
>             // python::tuple row = tuple[i].get() converted to 
tuple 
>           
>             for (int j=0; j<row.size(); j++){
>     vrow.push_back(BOOST_PYTHON_CONVERSION::from_python(row[i].get
(),
>                             python::type<double>()));
>             }
>             vd[i] = vrow;
>         }
>     }
> 
>     The other alternative I see is to do something like
>     vd[i] = BOOST_PYTHON_CONVERSION::from_python(tuple[i].get(),
>                 python::type< vector<double> >());
>     I did create a wrapper for vector<double> which works. However,
>     the above didn't work though it compiled. Not sure why.
> 
> Thanks,
> Elaine