!!$
!!$
!!$ MLD2P4 version 2.0
!!$ MultiLevel Domain Decomposition Parallel Preconditioners Package
!!$ based on PSBLAS (Parallel Sparse BLAS version 3.3)
!!$
!!$ (C) Copyright 2008, 2010, 2012, 2015
!!$
!!$ 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_zprecinit.f90
!
! Subroutine: mld_zprecinit
! Version: complex
!
! This routine allocates and initializes the preconditioner data structure,
! according to the preconditioner type chosen by the user.
!
! A default preconditioner is set for each preconditioner type
! specified by the user:
!
! 'NOPREC' - no preconditioner
!
! 'DIAG' - diagonal preconditioner
!
! 'PJAC' - point Jacobi preconditioner
!
! 'BJAC' - block Jacobi preconditioner, with ILU(0)
! on the local blocks
!
! 'AS' - Restricted Additive Schwarz (RAS), with
! overlap 1 and ILU(0) on the local submatrices
!
! 'ML' - Multilevel hybrid preconditioner (additive on the
! same level and multiplicative through the levels),
! with 2 levels, pre and post-smoothing, RAS with
! overlap 1 and ILU(0) on the local blocks is
! applied as post-smoother at each level, but the
! coarsest one; four sweeps of the block-Jacobi solver,
! with LU from UMFPACK on the blocks, are applied at
! the coarsest level, on the distributed coarse matrix.
! The smoothed aggregation algorithm with threshold 0
! is used to build the coarse matrix.
!
! For the multilevel preconditioners, the levels are numbered in increasing
! order starting from the finest one, i.e. level 1 is the finest level.
!
!
! Arguments:
! p - type(mld_zprec_type), input/output.
! The preconditioner data structure.
! ptype - character(len=*), input.
! The type of preconditioner. Its values are 'NOPREC',
! 'DIAG', 'BJAC', 'AS', 'ML' (and the corresponding
! lowercase strings).
! info - integer, output.
! Error code.
! nlev - integer, optional, input.
! The number of levels of the multilevel preconditioner.
! If nlev is not present and ptype='ML', then nlev=2
! is assumed. If ptype /= 'ML', nlev is ignored.
!
subroutine mld_zprecinit(p,ptype,info,nlev)
use psb_base_mod
use mld_z_prec_mod, mld_protect_name => mld_zprecinit
use mld_z_jac_smoother
use mld_z_as_smoother
use mld_z_id_solver
use mld_z_diag_solver
use mld_z_ilu_solver
#if defined(HAVE_UMF_)
use mld_z_umf_solver
#endif
#if defined(HAVE_SLU_)
use mld_z_slu_solver
#endif
implicit none
! Arguments
type(mld_zprec_type), intent(inout) :: p
character(len=*), intent(in) :: ptype
integer(psb_ipk_), intent(out) :: info
integer(psb_ipk_), optional, intent(in) :: nlev
! Local variables
integer(psb_ipk_) :: nlev_, ilev_
real(psb_dpk_) :: thr, scale
character(len=*), parameter :: name='mld_precinit'
info = psb_success_
if (allocated(p%precv)) then
call mld_precfree(p,info)
if (info /= psb_success_) then
! Do we want to do something?
endif
endif
p%coarse_aggr_size = -1
select case(psb_toupper(ptype(1:len_trim(ptype))))
case ('NOPREC','NONE')
nlev_ = 1
ilev_ = 1
allocate(p%precv(nlev_),stat=info)
allocate(mld_z_base_smoother_type :: p%precv(ilev_)%sm, stat=info)
if (info /= psb_success_) return
allocate(mld_z_id_solver_type :: p%precv(ilev_)%sm%sv, stat=info)
call p%precv(ilev_)%default()
case ('JAC','DIAG','JACOBI')
nlev_ = 1
ilev_ = 1
allocate(p%precv(nlev_),stat=info)
allocate(mld_z_jac_smoother_type :: p%precv(ilev_)%sm, stat=info)
if (info /= psb_success_) return
allocate(mld_z_diag_solver_type :: p%precv(ilev_)%sm%sv, stat=info)
call p%precv(ilev_)%default()
case ('BJAC')
nlev_ = 1
ilev_ = 1
allocate(p%precv(nlev_),stat=info)
allocate(mld_z_jac_smoother_type :: p%precv(ilev_)%sm, stat=info)
if (info /= psb_success_) return
allocate(mld_z_ilu_solver_type :: p%precv(ilev_)%sm%sv, stat=info)
call p%precv(ilev_)%default()
case ('AS')
nlev_ = 1
ilev_ = 1
allocate(p%precv(nlev_),stat=info)
allocate(mld_z_as_smoother_type :: p%precv(ilev_)%sm, stat=info)
if (info /= psb_success_) return
allocate(mld_z_ilu_solver_type :: p%precv(ilev_)%sm%sv, stat=info)
call p%precv(ilev_)%default()
case ('ML')
if (present(nlev)) then
nlev_ = max(1,nlev)
p%n_prec_levs = nlev_
else
nlev_ = 3
p%n_prec_levs = -ione
end if
ilev_ = 1
allocate(p%precv(nlev_),stat=info)
allocate(mld_z_as_smoother_type :: p%precv(ilev_)%sm, stat=info)
if (info /= psb_success_) return
allocate(mld_z_ilu_solver_type :: p%precv(ilev_)%sm%sv, stat=info)
call p%precv(ilev_)%default()
if (nlev_ == 1) return
do ilev_ = 2, nlev_ -1
allocate(mld_z_as_smoother_type :: p%precv(ilev_)%sm, stat=info)
if (info /= psb_success_) return
allocate(mld_z_ilu_solver_type :: p%precv(ilev_)%sm%sv, stat=info)
call p%precv(ilev_)%default()
end do
ilev_ = nlev_
allocate(mld_z_jac_smoother_type :: p%precv(ilev_)%sm, stat=info)
if (info /= psb_success_) return
#if defined(HAVE_UMF_)
allocate(mld_z_umf_solver_type :: p%precv(ilev_)%sm%sv, stat=info)
#elif defined(HAVE_SLU_)
allocate(mld_z_slu_solver_type :: p%precv(ilev_)%sm%sv, stat=info)
#else
allocate(mld_z_ilu_solver_type :: p%precv(ilev_)%sm%sv, stat=info)
#endif
call p%precv(ilev_)%default()
p%precv(ilev_)%parms%coarse_solve = mld_bjac_
call p%precv(ilev_)%set(mld_smoother_sweeps_,4_psb_ipk_,info)
call p%precv(ilev_)%set(mld_sub_restr_,psb_none_,info)
call p%precv(ilev_)%set(mld_sub_prol_,psb_none_,info)
call p%precv(ilev_)%set(mld_sub_ovr_,izero,info)
thr = 0.05
scale = 1.0
do ilev_=1,nlev_
call p%precv(ilev_)%set(mld_aggr_thresh_,thr,info)
call p%precv(ilev_)%set(mld_aggr_scale_,scale,info)
end do
case default
write(psb_err_unit,*) name,&
&': Warning: Unknown preconditioner type request "',ptype,'"'
info = psb_err_pivot_too_small_
end select
end subroutine mld_zprecinit