I have a native Windows library written in C++ and compiled with the MSVC compiler which contains one class (we’ll call it MyClass since I can’t provide the actual code for security reasons). MyClass has some std::vector<double> members that serve as input data to a MyClass member function (void myFun()–no input or output args) and also has some std::vector<double> members that serve as output parameters from that function.
I have also used clibgen to build a shared library so that MATLAB can use MyClass. However, I need to make sure that the outputs I get when both matlab and C++ call the function are EXACTLY the same, which I haven’t been able to achieve. To test equality between matlab and c++ I am doing the following:
Create a MyClass object in c++ (cppobj)
Populate the input parameters of cppobj
Run myFun() from cppobj
Write the input and output (all elements) of cppobj to binary files
Load the data of these binary files into two matlab objects, one with both inputs and outputs (matobj_cppout), and one with just inputs (matobj_matout)
Run myFun() on matobj_matout
Compare the output parameters of matobj_cppout and matobj_matout
I’ve calculated small differences in the output values even though they SHOULD be exactly the same, since the function is deterministic and the input parameters in matobj_cppout and matobj_matout are identical. This leads me to believe that MATLAB is doing some kind of conversion either when the binary files or read or when the values are stored to the native MyClass object using the "clib" functionality. I’ve verified that I’m using fp:precise both when building the native library and when running clibgen.
Any ideas of what could be causing these discrepancies?I have a native Windows library written in C++ and compiled with the MSVC compiler which contains one class (we’ll call it MyClass since I can’t provide the actual code for security reasons). MyClass has some std::vector<double> members that serve as input data to a MyClass member function (void myFun()–no input or output args) and also has some std::vector<double> members that serve as output parameters from that function.
I have also used clibgen to build a shared library so that MATLAB can use MyClass. However, I need to make sure that the outputs I get when both matlab and C++ call the function are EXACTLY the same, which I haven’t been able to achieve. To test equality between matlab and c++ I am doing the following:
Create a MyClass object in c++ (cppobj)
Populate the input parameters of cppobj
Run myFun() from cppobj
Write the input and output (all elements) of cppobj to binary files
Load the data of these binary files into two matlab objects, one with both inputs and outputs (matobj_cppout), and one with just inputs (matobj_matout)
Run myFun() on matobj_matout
Compare the output parameters of matobj_cppout and matobj_matout
I’ve calculated small differences in the output values even though they SHOULD be exactly the same, since the function is deterministic and the input parameters in matobj_cppout and matobj_matout are identical. This leads me to believe that MATLAB is doing some kind of conversion either when the binary files or read or when the values are stored to the native MyClass object using the "clib" functionality. I’ve verified that I’m using fp:precise both when building the native library and when running clibgen.
Any ideas of what could be causing these discrepancies? I have a native Windows library written in C++ and compiled with the MSVC compiler which contains one class (we’ll call it MyClass since I can’t provide the actual code for security reasons). MyClass has some std::vector<double> members that serve as input data to a MyClass member function (void myFun()–no input or output args) and also has some std::vector<double> members that serve as output parameters from that function.
I have also used clibgen to build a shared library so that MATLAB can use MyClass. However, I need to make sure that the outputs I get when both matlab and C++ call the function are EXACTLY the same, which I haven’t been able to achieve. To test equality between matlab and c++ I am doing the following:
Create a MyClass object in c++ (cppobj)
Populate the input parameters of cppobj
Run myFun() from cppobj
Write the input and output (all elements) of cppobj to binary files
Load the data of these binary files into two matlab objects, one with both inputs and outputs (matobj_cppout), and one with just inputs (matobj_matout)
Run myFun() on matobj_matout
Compare the output parameters of matobj_cppout and matobj_matout
I’ve calculated small differences in the output values even though they SHOULD be exactly the same, since the function is deterministic and the input parameters in matobj_cppout and matobj_matout are identical. This leads me to believe that MATLAB is doing some kind of conversion either when the binary files or read or when the values are stored to the native MyClass object using the "clib" functionality. I’ve verified that I’m using fp:precise both when building the native library and when running clibgen.
Any ideas of what could be causing these discrepancies? clibgen, native, c++ MATLAB Answers — New Questions

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