You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
amg4psblas/mlprec/mld_dilu_bld.f90

288 lines
11 KiB
Fortran

!!$
!!$
!!$ MLD2P4 version 1.1
!!$ MultiLevel Domain Decomposition Parallel Preconditioners Package
!!$ based on PSBLAS (Parallel Sparse BLAS version 2.3.1)
!!$
!!$ (C) Copyright 2008,2009
!!$
!!$ Salvatore Filippone University of Rome Tor Vergata
!!$ Alfredo Buttari CNRS-IRIT, Toulouse
!!$ Pasqua D'Ambra ICAR-CNR, Naples
!!$ Daniela di Serafino Second University of Naples
!!$
!!$ 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 MLD2P4 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 MLD2P4 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.
!!$
!!$
! File: mld_dilu_bld.f90
!
! Subroutine: mld_dilu_bld
! Version: real
!
! This routine computes an incomplete LU (ILU) factorization of the diagonal
! blocks of a distributed matrix. This factorization is used to build the
! 'base preconditioner' (block-Jacobi preconditioner/solver, Additive Schwarz
! preconditioner) corresponding to a certain level of a multilevel preconditioner.
!
! The following factorizations are available:
! - ILU(k), i.e. ILU factorization with fill-in level k,
! - MILU(k), i.e. modified ILU factorization with fill-in level k,
! - ILU(k,t), i.e. ILU with threshold (i.e. drop tolerance) t and k additional
! entries in each row of the L and U factors with respect to the initial
! sparsity pattern.
! Note that the meaning of k in ILU(k,t) is different from that in ILU(k) and
! MILU(k).
!
! For details on the above factorizations see
! Y. Saad, Iterative Methods for Sparse Linear Systems, Second Edition,
! SIAM, 2003, Chapter 10.
!
! Note that that this routine handles the ILU(0) factorization separately,
! through mld_ilu0_fact, for performance reasons.
!
!
! Arguments:
! a - type(psb_dspmat_type), input.
! The sparse matrix structure containing the local matrix.
! Note that if p%iprcparm(mld_sub_ovr_) > 0, i.e. the
! 'base' Additive Schwarz preconditioner has overlap greater than
! 0, and p%iprcparm(mld_sub_ren_) = 0, i.e. a reordering of the
! matrix has not been performed (see mld_fact_bld), then a contains
! only the 'original' local part of the distributed matrix,
! i.e. the rows of the matrix held by the calling process according
! to the initial data distribution.
! p - type(mld_dbaseprec_type), input/output.
! The 'base preconditioner' data structure. In input, p%iprcparm
! contains information on the type of factorization to be computed.
! In output, p%av(mld_l_pr_) and p%av(mld_u_pr_) contain the
! incomplete L and U factors (without their diagonals), and p%d
! contains the diagonal of the incomplete U factor. For more
! details on p see its description in mld_prec_type.f90.
! info - integer, output.
! Error code.
! blck - type(psb_dspmat_type), input, optional.
! The sparse matrix structure containing the remote rows of the
! distributed matrix, that have been retrieved by mld_as_bld
! to build an Additive Schwarz base preconditioner with overlap
! greater than 0. If the overlap is 0 or the matrix has been reordered
! (see mld_fact_bld), then blck does not contain any row.
!
subroutine mld_dilu_bld(a,p,upd,info,blck)
use psb_sparse_mod
use mld_inner_mod, mld_protect_name => mld_dilu_bld
implicit none
! Arguments
type(psb_d_sparse_mat), intent(in), target :: a
type(mld_dbaseprec_type), intent(inout) :: p
character, intent(in) :: upd
integer, intent(out) :: info
type(psb_d_sparse_mat), intent(in), optional :: blck
! Local Variables
integer :: i, nztota, err_act, n_row, nrow_a
character :: trans, unitd
integer :: debug_level, debug_unit
integer :: ictxt,np,me
character(len=20) :: name, ch_err
if(psb_get_errstatus().ne.0) return
info=psb_success_
name='mld_dilu_bld'
call psb_erractionsave(err_act)
debug_unit = psb_get_debug_unit()
debug_level = psb_get_debug_level()
ictxt = psb_cd_get_context(p%desc_data)
call psb_info(ictxt, me, np)
if (debug_level >= psb_debug_outer_) &
& write(debug_unit,*) me,' ',trim(name),' start'
trans = 'N'
unitd = 'U'
n_row = psb_cd_get_local_rows(p%desc_data)
if (psb_toupper(upd) == 'F') then
!
! Check the memory available to hold the incomplete L and U factors
! and allocate it if needed
!
if (allocated(p%av)) then
if (size(p%av) < mld_bp_ilu_avsz_) then
do i=1, size(p%av)
call p%av(i)%free()
enddo
deallocate(p%av,stat=info)
endif
end if
if (.not.allocated(p%av)) then
allocate(p%av(mld_max_avsz_),stat=info)
if (info /= psb_success_) then
call psb_errpush(psb_err_alloc_dealloc_,name)
goto 9999
end if
endif
nrow_a = a%get_nrows()
nztota = a%get_nzeros()
if (present(blck)) then
nztota = nztota + blck%get_nzeros()
end if
call p%av(mld_l_pr_)%csall(n_row,n_row,info,nztota)
if (info == psb_success_) call p%av(mld_u_pr_)%csall(n_row,n_row,info,nztota)
if(info /= psb_success_) then
info=psb_err_from_subroutine_
ch_err='psb_sp_all'
call psb_errpush(info,name,a_err=ch_err)
goto 9999
end if
if (allocated(p%d)) then
if (size(p%d) < n_row) then
deallocate(p%d)
endif
endif
if (.not.allocated(p%d)) then
allocate(p%d(n_row),stat=info)
if (info /= psb_success_) then
call psb_errpush(psb_err_from_subroutine_,name,a_err='Allocate')
goto 9999
end if
endif
select case(p%iprcparm(mld_sub_solve_))
case (mld_ilu_t_)
!
! ILU(k,t)
!
select case(p%iprcparm(mld_sub_fillin_))
case(:-1)
! Error: fill-in <= -1
call psb_errpush(psb_err_input_value_invalid_i_,name,i_err=(/3,p%iprcparm(mld_sub_fillin_),0,0,0/))
goto 9999
case(0:)
! Fill-in >= 0
call mld_ilut_fact(p%iprcparm(mld_sub_fillin_),p%rprcparm(mld_sub_iluthrs_),&
& a, p%av(mld_l_pr_),p%av(mld_u_pr_),p%d,info,blck=blck)
end select
if(info /= psb_success_) then
info=psb_err_from_subroutine_
ch_err='mld_ilut_fact'
call psb_errpush(info,name,a_err=ch_err)
goto 9999
end if
case(mld_ilu_n_,mld_milu_n_)
!
! ILU(k) and MILU(k)
!
select case(p%iprcparm(mld_sub_fillin_))
case(:-1)
! Error: fill-in <= -1
call psb_errpush(psb_err_input_value_invalid_i_,name,i_err=(/3,p%iprcparm(mld_sub_fillin_),0,0,0/))
goto 9999
case(0)
! Fill-in 0
! Separate implementation of ILU(0) for better performance.
! There seems to be a problem with the separate implementation of MILU(0),
! contained into mld_ilu0_fact. This must be investigated. For the time being,
! resort to the implementation of MILU(k) with k=0.
if (p%iprcparm(mld_sub_solve_) == mld_ilu_n_) then
call mld_ilu0_fact(p%iprcparm(mld_sub_solve_),a,p%av(mld_l_pr_),p%av(mld_u_pr_),&
& p%d,info,blck=blck,upd=upd)
else
call mld_iluk_fact(p%iprcparm(mld_sub_fillin_),p%iprcparm(mld_sub_solve_),&
& a,p%av(mld_l_pr_),p%av(mld_u_pr_),p%d,info,blck=blck)
endif
case(1:)
! Fill-in >= 1
! The same routine implements both ILU(k) and MILU(k)
call mld_iluk_fact(p%iprcparm(mld_sub_fillin_),p%iprcparm(mld_sub_solve_),&
& a,p%av(mld_l_pr_),p%av(mld_u_pr_),p%d,info,blck=blck)
end select
if (info /= psb_success_) then
info=psb_err_from_subroutine_
ch_err='mld_iluk_fact'
call psb_errpush(info,name,a_err=ch_err)
goto 9999
end if
case default
! If we end up here, something was wrong up in the call chain.
call psb_errpush(psb_err_alloc_dealloc_,name)
goto 9999
end select
else
! Here we should add checks for reuse of L and U.
! For the time being just throw an error.
info = 31
call psb_errpush(info, name, i_err=(/3,0,0,0,0/),a_err=upd)
goto 9999
!
! What is an update of a factorization??
! A first attempt could be to reuse EXACTLY the existing indices
! as if it was an ILU(0) (since, effectively, the sparsity pattern
! should not grow beyond what is already there).
!
call mld_ilu0_fact(p%iprcparm(mld_sub_solve_),a,&
& p%av(mld_l_pr_),p%av(mld_u_pr_),&
& p%d,info,blck=blck,upd=upd)
end if
call p%av(mld_l_pr_)%set_asb()
call p%av(mld_l_pr_)%trim()
call p%av(mld_u_pr_)%set_asb()
call p%av(mld_u_pr_)%trim()
if (debug_level >= psb_debug_outer_) &
& write(debug_unit,*) me,' ',trim(name),' end'
call psb_erractionrestore(err_act)
return
9999 continue
call psb_erractionrestore(err_act)
if (err_act.eq.psb_act_abort_) then
call psb_error()
return
end if
return
end subroutine mld_dilu_bld