!    This file is part of ELPA.
!
!    The ELPA library was originally created by the ELPA consortium,
!    consisting of the following organizations:
!
!    - Max Planck Computing and Data Facility (MPCDF), formerly known as
!      Rechenzentrum Garching der Max-Planck-Gesellschaft (RZG),
!    - Bergische Universität Wuppertal, Lehrstuhl für angewandte
!      Informatik,
!    - Technische Universität München, Lehrstuhl für Informatik mit
!      Schwerpunkt Wissenschaftliches Rechnen ,
!    - Fritz-Haber-Institut, Berlin, Abt. Theorie,
!    - Max-Plack-Institut für Mathematik in den Naturwissenschaften,
!      Leipzig, Abt. Komplexe Strukutren in Biologie und Kognition,
!      and
!    - IBM Deutschland GmbH
!
!    This particular source code file contains additions, changes and
!    enhancements authored by Intel Corporation which is not part of
!    the ELPA consortium.
!
!    More information can be found here:
!    http://elpa.mpcdf.mpg.de/
!
!    ELPA is free software: you can redistribute it and/or modify
!    it under the terms of the version 3 of the license of the
!    GNU Lesser General Public License as published by the Free
!    Software Foundation.
!
!    ELPA is distributed in the hope that it will be useful,
!    but WITHOUT ANY WARRANTY; without even the implied warranty of
!    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
!    GNU Lesser General Public License for more details.
!
!    You should have received a copy of the GNU Lesser General Public License
!    along with ELPA.  If not, see <http://www.gnu.org/licenses/>
!
!    ELPA reflects a substantial effort on the part of the original
!    ELPA consortium, and we ask you to respect the spirit of the
!    license that we chose: i.e., please contribute any changes you
!    may have back to the original ELPA library distribution, and keep
!    any derivatives of ELPA under the same license that we chose for
!    the original distribution, the GNU Lesser General Public License.
!
!
! ELPA1 -- Faster replacements for ScaLAPACK symmetric eigenvalue routines
!
! Copyright of the original code rests with the authors inside the ELPA
! consortium. The copyright of any additional modifications shall rest
! with their original authors, but shall adhere to the licensing terms
! distributed along with the original code in the file "COPYING".
!
! Author: A. Marek, MPCDF



#include "../../general/sanity.X90"

      use precision
      use elpa1_auxiliary_impl, only : elpa_solve_tridi_&
      &PRECISION&
      &_impl
      use elpa
      use elpa_abstract_impl
      implicit none
      integer(kind=ik)            :: na, nev, ldq, nblk, matrixCols, mpi_comm_rows, mpi_comm_cols
      real(kind=REAL_DATATYPE)    :: d(na), e(na)
#ifdef USE_ASSUMED_SIZE
      real(kind=REAL_DATATYPE)    :: q(ldq,*)
#else
      real(kind=REAL_DATATYPE)    :: q(ldq,matrixCols)
#endif

      logical, intent(in)         :: wantDebug
      logical                     :: success
      integer(kind=iK)            :: successInternal
      class(elpa_t), pointer      :: obj

      !call timer%start("elpa_solve_tridi_&
      !&PRECISION&
      !&_legacy_interface")

      success = .false.

      if (elpa_init(CURRENT_API_VERSION) /= ELPA_OK) then
        print *, "ELPA API version not supported"
        success = .false.
      endif

      obj => elpa_allocate()

      call obj%set("na", na)
      call obj%set("nev", nev)
      call obj%set("local_nrows", ldq)
      call obj%set("local_ncols", matrixCols)
      call obj%set("nblk", nblk)

      call obj%set("mpi_comm_rows", mpi_comm_rows)
      call obj%set("mpi_comm_cols", mpi_comm_cols)

      if (obj%setup() .ne. ELPA_OK) then
        print *, "Cannot setup ELPA instance"
        success = .false.
        return
      endif

      if (wantDebug) then
        call obj%set("debug",1)
      endif

      select type(obj)
        class is (elpa_abstract_impl_t)
          success = elpa_solve_tridi_&
          &PRECISION&
          &_impl(obj, d, e, q)
          !call obj%solve_tridi(d(1:na), e(1:na), q(1:ldq,1:matrixCols), successInternal)

          if (.not.(success)) then
            print *, "Cannot run solve_tridi"
            return
          endif
      end select
      call elpa_deallocate(obj)

      call elpa_uninit()

     !call timer%stop("elpa_solve_tridi_&
     !&PRECISION&
     !&_legacy_interface")

#undef REALCASE
#undef COMPLEXCASE
#undef DOUBLE_PRECISION
#undef SINGLE_PRECISION

! vim: syntax=fortran