* \param [in] st - the structure of grid ( \b without considering ghost cells).
* \param [in] part - the part in the structure ( \b without considering ghost cells) contained in grid whose structure is defined by \a st.
* \param [in] factor - the factor, the tuples in \a da will be multiply by.
* \param [in] st - the structure of grid ( \b without considering ghost cells).
* \param [in] part - the part in the structure ( \b without considering ghost cells) contained in grid whose structure is defined by \a st.
* \param [in] factor - the factor, the tuples in \a da will be multiply by.