\descript{Get \texttt{schur} local unkown number.}
         {Get the number of unkowns in the part of the \texttt{schur}
         local to the \texttt{MPI }task.\\
         With this information, user can allocate the local part of
         the \texttt{schur} complement and give to \pastix{}
         with \texttt{pastix\_setSchurArray}
         (\ref{proto:pastix_setSchurArray})\\
         This function must be called after the analysis and before
         the numerical factorization.}

