Example of embedding python into C++ application

embed_python.cc

/*

VC++ Directories
----------------
  Include Directories: C:\Anaconda3\include
  Library Directories: C:\Anaconda3\libs

*/

#include <iostream>
#include <string>

#include <Python.h>


void pyCmd() {
  PyRun_SimpleString("import scipy as np\nprint(np.__version__)");
}


std::string CallPythonPlugIn(const std::string& s) {
  Py_Initialize();

  // Import the module "plugin" (from the file "plugin.py")
  PyObject* moduleName = PyUnicode_FromString("plugin");
  PyObject* pluginModule = PyImport_Import(moduleName);

  // Retrieve the "transform()" function from the module.
  PyObject* transformFunc = PyObject_GetAttrString(pluginModule, "transform");

  // Build an argument tuple containing the string.
  PyObject* argsTuple = Py_BuildValue("(s)", s.c_str());

  // Invoke the function, passing the argument tuple.
  PyObject* result = PyObject_CallObject(transformFunc, argsTuple);

  // Convert the result to a std::string.
  //std::string resultStr(PyString_AsString(result));
  char *my_result = 0;

  PyObject * temp_bytes = PyUnicode_AsEncodedString(result, "ASCII", "strict"); // Owned reference
  if (temp_bytes != NULL) {
    my_result = PyBytes_AS_STRING(temp_bytes); // Borrowed pointer
  } else {
    // TODO: Handle encoding error.
  }

  Py_DECREF(temp_bytes);

  // Free all temporary Python objects.
  Py_DECREF(moduleName);
  Py_DECREF(pluginModule);
  Py_DECREF(transformFunc);
  Py_DECREF(argsTuple);
  Py_DECREF(result);

  Py_Finalize();

  return my_result;
}

int main(int argc, char** argv) {
  std::string input;
  std::cout << "Enter string to transform: ";
  std::getline(std::cin, input);
  std::string transformed = CallPythonPlugIn(input);
  std::cout << "The transformed string is: " << transformed.c_str() <<
  std::endl;
}