将输入转换为类时C ++ Boost矩阵错误

Question

First of all, I use boost library, and if it changes anything, the code is compiled on a Windows Machine. The code itself contains a lot more of function acting upon matrices but only this one triggers the error. Well, I am trying to transform matrix like : {001 100 010} To something like : {1 3 2} But strangely I can't compile my code and I can't find the error so I would be glad if anyone could help me. Below the code :

using namespace boost::numeric::ublas;

typedef matrix <float, row_major, unbounded_array<float>> MATRIXf;
MATRIXf matrix_to_class (const MATRIXf inputM)
{   
    MATRIXf output;
    for (std::size_t line = 0; line < inputM.size1(); line++)
    {                                                           
        for (std::size_t column = 0; column < inputM.size2(); column++)
        {                                                       
            if (column == 1)                                            
            {                                                   
                output.insert_element(line,0.0,column);
            }                                                   
        }                                                       
    }

    return output;
}       

Here is the error code:

1>c:\program files (x86)\microsoft visual studio 14.0\vc\include\xutility(2372): error C4996: 'std::copy::_Unchecked_iterators::_Deprecate': Call to 'std::copy' with parameters that may be unsafe - this call relies on the caller to check that the passed values are correct. To disable this warning, use -D_SCL_SECURE_NO_WARNINGS. See documentation on how to use Visual C++ 'Checked Iterators'
1>  c:\program files (x86)\microsoft visual studio 14.0\vc\include\xutility(2372): note: see declaration of 'std::copy::_Unchecked_iterators::_Deprecate'
1>  e:\c++ libraries\general\boost_1_65_0\boost\numeric\ublas\storage.hpp(204): note: see reference to function template instantiation '_OutIt *std::copy<float*,float*>(_InIt,_InIt,_OutIt)' being compiled
1>          with
1>          [
1>              _OutIt=float *,
1>              _InIt=float *
1>          ]
1>  e:\c++ libraries\general\boost_1_65_0\boost\numeric\ublas\storage.hpp(201): note: while compiling class template member function 'boost::numeric::ublas::unbounded_array<float,std::allocator<T>> &boost::numeric::ublas::unbounded_array<T,std::allocator<T>>::operator =(const boost::numeric::ublas::unbounded_array<T,std::allocator<T>> &)'
1>          with
1>          [
1>              T=float
1>          ]
1>  e:\c++ libraries\general\boost_1_65_0\boost\numeric\ublas\matrix.hpp(310): note: see reference to function template instantiation 'boost::numeric::ublas::unbounded_array<float,std::allocator<T>> &boost::numeric::ublas::unbounded_array<T,std::allocator<T>>::operator =(const boost::numeric::ublas::unbounded_array<T,std::allocator<T>> &)' being compiled
1>          with
1>          [
1>              T=float
1>          ]
1>  e:\c++ libraries\general\boost_1_65_0\boost\numeric\ublas\matrix.hpp(102): note: see reference to class template instantiation 'boost::numeric::ublas::unbounded_array<float,std::allocator<T>>' being compiled
1>          with
1>          [
1>              T=float
1>          ]
1>  g:\c++ python\travail\visualstudio\visualstudio\guigui\neural net\neural net\utils.hpp(21): note: see reference to class template instantiation 'boost::numeric::ublas::matrix<float,boost::numeric::ublas::row_major,boost::numeric::ublas::unbounded_array<float,std::allocator<T>>>' being compiled
1>          with
1>          [
1>              T=float
1>          ]
1>c:\program files (x86)\microsoft visual studio 14.0\vc\include\xmemory(102): error C4996: 'std::uninitialized_copy::_Unchecked_iterators::_Deprecate': Call to 'std::uninitialized_copy' with parameters that may be unsafe - this call relies on the caller to check that the passed values are correct. To disable this warning, use -D_SCL_SECURE_NO_WARNINGS. See documentation on how to use Visual C++ 'Checked Iterators'
1>  c:\program files (x86)\microsoft visual studio 14.0\vc\include\xmemory(102): note: see declaration of 'std::uninitialized_copy::_Unchecked_iterators::_Deprecate'
1>  e:\c++ libraries\general\boost_1_65_0\boost\numeric\ublas\storage.hpp(94): note: see reference to function template instantiation '_FwdIt *std::uninitialized_copy<const float*,float*>(_InIt,_InIt,_FwdIt)' being compiled
1>          with
1>          [
1>              _FwdIt=float *,
1>              _InIt=const float *
1>          ]
1>  e:\c++ libraries\general\boost_1_65_0\boost\numeric\ublas\storage.hpp(89): note: while compiling class template member function 'boost::numeric::ublas::unbounded_array<float,std::allocator<T>>::unbounded_array(const boost::numeric::ublas::unbounded_array<T,std::allocator<T>> &)'
1>          with
1>          [
1>              T=float
1>          ]
1>  e:\c++ libraries\general\boost_1_65_0\boost\numeric\ublas\matrix.hpp(162): note: see reference to function template instantiation 'boost::numeric::ublas::unbounded_array<float,std::allocator<T>>::unbounded_array(const boost::numeric::ublas::unbounded_array<T,std::allocator<T>> &)' being compiled
1>          with
1>          [
1>              T=float
1>          ]
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

Trying to locate the error brings me to the function above. Thanks in advance.

Answer 1

Near the end of the first error message is the text, "To disable this warning, use -D_SCL_SECURE_NO_WARNINGS". https://msdn.microsoft.com/en-us/library/ttcz0bys.aspx has a more detailed discussion of warnings and checked iterators. In essence, Microsoft created "safe" mutations of Standard C++ functions to help developers avoid invalid iterator usage. The error message suggests that you define _SCL_SECURE_NO_WARNINGS. This can be done in the project properties C/C++/Preprocessor/Preprocessor Definitions. In a project I worked on in the past, we disabled all the "safe" versions of the functions because of the performance hit.

You may be interested in reading the above Microsoft page for more information about the checked iterator topic.