!   
!                Parallel Sparse BLAS  version 3.5
!      (C) Copyright 2006-2018
!        Salvatore Filippone    
!        Alfredo Buttari      
!   
!    Redistribution and use in source and binary forms, with or without
!    modification, are permitted provided that the following conditions
!    are met:
!      1. Redistributions of source code must retain the above copyright
!         notice, this list of conditions and the following disclaimer.
!      2. Redistributions in binary form must reproduce the above copyright
!         notice, this list of conditions, and the following disclaimer in the
!         documentation and/or other materials provided with the distribution.
!      3. The name of the PSBLAS group or the names of its contributors may
!         not be used to endorse or promote products derived from this
!         software without specific written permission.
!   
!    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
!    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
!    TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
!    PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE PSBLAS GROUP OR ITS CONTRIBUTORS
!    BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
!    CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
!    SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
!    INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
!    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
!    ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
!    POSSIBILITY OF SUCH DAMAGE.
!   
!    
module psb_s_mat_dist_mod
  use psb_base_mod, only :  psb_ipk_, psb_spk_, psb_desc_type, psb_parts, &
       & psb_sspmat_type, psb_s_base_sparse_mat, psb_s_vect_type

  interface psb_matdist
    subroutine psb_smatdist(a_glob, a, ictxt, desc_a,&
         & info, parts, v, inroot,fmt,mold)
      !
      ! an utility subroutine to distribute a matrix among processors
      ! according to a user defined data distribution, using
      ! sparse matrix subroutines.
      !
      !  type(psb_sspmat)                       :: a_glob
      !     on entry: this contains the global sparse matrix as follows:
      !
      !  type(psb_sspmat_type)                            :: a
      !     on exit : this will contain the local sparse matrix.
      !
      !       interface parts
      !         !   .....user passed subroutine.....
      !         subroutine parts(global_indx,n,np,pv,nv)
      !           implicit none
      !           integer(psb_ipk_), intent(in)  :: global_indx, n, np
      !           integer(psb_ipk_), intent(out) :: nv
      !           integer(psb_ipk_), intent(out) :: pv(*)
      !
      !       end subroutine parts
      !       end interface
      !     on entry:  subroutine providing user defined data distribution.
      !        for each global_indx the subroutine should return
      !        the list  pv of all processes owning the row with
      !        that index; the list will contain nv entries.
      !        usually nv=1; if nv >1 then we have an overlap in the data
      !        distribution.
      !
      !  integer(psb_ipk_) :: ictxt
      !     on entry: the PSBLAS parallel environment context.
      !
      !  type (desc_type)                  :: desc_a
      !     on exit : the updated array descriptor
      !
      !
      !  integer(psb_ipk_), optional    :: inroot
      !     on entry: specifies processor holding a_glob. default: 0
      !     on exit : unchanged.
      !
      import :: psb_ipk_, psb_sspmat_type, psb_spk_, psb_desc_type,&
           & psb_s_base_sparse_mat, psb_s_vect_type, psb_parts
      implicit none

      ! parameters
      type(psb_sspmat_type)      :: a_glob
      integer(psb_ipk_) :: ictxt
      type(psb_sspmat_type)      :: a
      type(psb_desc_type)        :: desc_a
      integer(psb_ipk_), intent(out)       :: info
      integer(psb_ipk_), optional       :: inroot
      character(len=*), optional :: fmt
      class(psb_s_base_sparse_mat), optional :: mold
      procedure(psb_parts), optional  :: parts
      integer(psb_ipk_), optional     :: v(:)
    end subroutine psb_smatdist
  end interface

end module psb_s_mat_dist_mod
