Embed Sympy in Qt C++ application

[J. Javan]

Hey guys,
I have a C++ application and I want to embed sympy in it.
Application is statically linked against python.
However, I'm facing a problem when importing sympy module which simply doesn't get imported.
Are there any examples on this?

Below is my code:

const char * python_home = "\"C:\\Program Files\\Python3.6.4\"";

int main(int argc, char *argv[])
{
    PyObject *pName = nullptr;

    PyObject *pModule = nullptr;

    PyObject *pDict = nullptr;

    PyObject *pFunc = nullptr;

    PyObject *pValue = nullptr;

    PyObject *pMainModule = nullptr;

    Py_SetProgramName((wchar_t *) APP_NAME);

    Py_Initialize();
    Py_SetPythonHome((wchar_t *) python_home);
    PyRun_SimpleString("import sys");


    PyRun_SimpleString("sys.path.append(\"C:\\Program Files\\Python3.6.4\")");
    if(PyErr_Occurred())
    {
        // error handling    }
    pName = PyBytes_FromString("sympy");
    if(nullptr == pName)
    {
        // error handling
    }

    // Below function call always fails
    pModule = PyImport_Import(pName);
    if(nullptr == pModule) 
    {
        PyObject *ptype, *ptraceback;
        PyObject *pystr = nullptr;
        char *str;
        PyObject *pErrMsg = nullptr;
        PyErr_Fetch(&ptype, &pErrMsg, &ptraceback);        
        str = PyBytes_AsString(pystr);    // str is always null
    }
    
    return 0;
}

I have Installed python and ran below command to install sympy:

pip3 install sympy

Dev Environment:
Qt_v5.9
Windows 7
Python_v3.6.4

[Kasper Peeters]

I know you didn't ask for this, but I can strongly recommend using pybind11 (https://github.com/pybind/pybind11) if you want nice C++ bindings for Python. It shields you from a lot of low-level details.

[J. Javan]

Thank you for your reply. I'll have a look.
I managed to get around the problem by simply changing below line of code

pName = PyBytes_FromString("sympy");

to

pModuleName = PyUnicode_FromString("sympy.combinatorics");