Class DiscontiguousMatrix

tests/test_buffers.cpp:217–257

A matrix that uses a discontiguous underlying memory block.

    // A matrix that uses a discontiguous underlying memory block.
    class DiscontiguousMatrix : public Matrix {
    public:
        DiscontiguousMatrix(py::ssize_t rows,
                            py::ssize_t cols,
                            py::ssize_t row_factor,
                            py::ssize_t col_factor)
            : Matrix(rows * row_factor, cols * col_factor), m_row_factor(row_factor),
              m_col_factor(col_factor) {
            print_created(this,
                          std::to_string(rows) + "(*" + std::to_string(row_factor) + ")x"
                              + std::to_string(cols) + "(*" + std::to_string(col_factor)
                              + ") matrix");
        }
        DiscontiguousMatrix(const DiscontiguousMatrix &) = delete;
        ~DiscontiguousMatrix() {
            print_destroyed(this,
                            std::to_string(rows() / m_row_factor) + "(*"
                                + std::to_string(m_row_factor) + ")x"
                                + std::to_string(cols() / m_col_factor) + "(*"
                                + std::to_string(m_col_factor) + ") matrix");
        }

        float operator()(py::ssize_t i, py::ssize_t j) const {
            return Matrix::operator()(i * m_row_factor, j * m_col_factor);
        }

        float &operator()(py::ssize_t i, py::ssize_t j) {
            return Matrix::operator()(i * m_row_factor, j * m_col_factor);
        }

        using Matrix::data;

        py::ssize_t rows() const { return Matrix::rows() / m_row_factor; }
        py::ssize_t cols() const { return Matrix::cols() / m_col_factor; }
        py::ssize_t row_factor() const { return m_row_factor; }
        py::ssize_t col_factor() const { return m_col_factor; }

    private:
        py::ssize_t m_row_factor;
        py::ssize_t m_col_factor;
    };
    py::class_<DiscontiguousMatrix, Matrix>(m, "DiscontiguousMatrix", py::buffer_protocol())
        .def(py::init<py::ssize_t, py::ssize_t, py::ssize_t, py::ssize_t>())