Method col_factor

tests/test_buffers.cpp:252–252

        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;