MatrixToNumpy.h

Go to the documentation of this file.

// Mantid Repository : https://github.com/mantidproject/mantid
//
// Copyright © 2012 ISIS Rutherford Appleton Laboratory UKRI,
//   NScD Oak Ridge National Laboratory, European Spallation Source,
//   Institut Laue - Langevin & CSNS, Institute of High Energy Physics, CAS
// SPDX - License - Identifier: GPL - 3.0 +
#pragma once
 
#include "MantidKernel/Matrix.h"
#include "MantidPythonInterface/core/Converters/CloneToNDArray.h"
#include "MantidPythonInterface/core/Converters/MatrixToNDArray.h"
#include "MantidPythonInterface/core/NDArray.h"
 
#include <type_traits>
 
#include <boost/mpl/and.hpp>
#include <boost/mpl/if.hpp>
 
namespace Mantid {
namespace PythonInterface {
namespace Policies {
 
namespace // anonymous
{
//-----------------------------------------------------------------------
// MPL helper structs
//-----------------------------------------------------------------------
template <typename T> struct is_matrix : boost::false_type {};
 
template <typename T> struct is_matrix<Kernel::Matrix<T>> : boost::true_type {};
 
//-----------------------------------------------------------------------
// MatrixRefToNumpyImpl - Policy for reference returns
//-----------------------------------------------------------------------
template <typename MatrixType, typename ConversionPolicy> struct MatrixRefToNumpyImpl {
  inline PyObject *operator()(const MatrixType &cmatrix) const {
    return Converters::MatrixToNDArray<typename MatrixType::value_type, ConversionPolicy>()(cmatrix);
  }
 
  inline PyTypeObject const *get_pytype() const { return ndarrayType(); }
};
 
template <typename T> struct MatrixRefToNumpy_Requires_Reference_To_Matrix_Return_Type {};
} // namespace
 
template <typename ConversionPolicy> struct MatrixRefToNumpy {
  // The boost::python framework calls return_value_policy::apply<T>::type
  template <class T> struct apply {
    // Typedef that removes and const or reference qualifiers from the return
    // type
    using non_const_type = typename std::remove_const<typename std::remove_reference<T>::type>::type;
    // MPL compile-time check that T is a reference to a Kernel::Matrix
    using type = typename boost::mpl::if_c<boost::mpl::and_<std::is_reference<T>, is_matrix<non_const_type>>::value,
                                           MatrixRefToNumpyImpl<non_const_type, ConversionPolicy>,
                                           MatrixRefToNumpy_Requires_Reference_To_Matrix_Return_Type<T>>::type;
  };
};
 
//-----------------------------------------------------------------------
// MatrixToNumpy return_value_policy
//-----------------------------------------------------------------------
namespace {
template <typename MatrixType> struct MatrixToNumpyImpl {
  inline PyObject *operator()(const MatrixType &cvector) const {
    return Converters::MatrixToNDArray<typename MatrixType::value_type, Converters::Clone>()(cvector);
  }
 
  inline PyTypeObject const *get_pytype() const { return ndarrayType(); }
};
 
template <typename T> struct MatrixToNumpy_Requires_Matrix_Return_By_Value {};
} // namespace
 
struct MatrixToNumpy {
  // The boost::python framework calls return_value_policy::apply<T>::type
  template <class T> struct apply {
    // Typedef that removes any const from the type
    using non_const_type = typename std::remove_const<T>::type;
    // MPL compile-time check that T is a std::vector
    using type = typename boost::mpl::if_c<is_matrix<non_const_type>::value,
                                           MatrixRefToNumpyImpl<non_const_type, Converters::Clone>,
                                           MatrixToNumpy_Requires_Matrix_Return_By_Value<T>>::type;
  };
};
} // namespace Policies
} // namespace PythonInterface
} // namespace Mantid