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/amgprec/impl/aggregator/amg_caggrmat_smth_bld.f90

353 lines
13 KiB
Fortran

!
!
! AMG4PSBLAS version 1.0
! Algebraic Multigrid Package
! based on PSBLAS (Parallel Sparse BLAS version 3.7)
!
! (C) Copyright 2021
!
! Salvatore Filippone
! Pasqua D'Ambra
! Fabio Durastante
!
! 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 AMG4PSBLAS 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 AMG4PSBLAS 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: amg_caggrmat_smth_bld.F90
!
! Subroutine: amg_caggrmat_smth_bld
! Version: complex
!
! This routine builds a coarse-level matrix A_C from a fine-level matrix A
! by using the Galerkin approach, i.e.
!
! A_C = P_C^T A P_C,
!
! where P_C is a prolongator from the coarse level to the fine one.
!
! The prolongator P_C is built according to a smoothed aggregation algorithm,
! i.e. it is obtained by applying a damped Jacobi smoother to the piecewise
! constant interpolation operator P corresponding to the fine-to-coarse level
! mapping built by the amg_aggrmap_bld subroutine:
!
! P_C = (I - omega*D^(-1)A) * P,
!
! where D is the diagonal matrix with main diagonal equal to the main diagonal
! of A, and omega is a suitable smoothing parameter. An estimate of the spectral
! radius of D^(-1)A, to be used in the computation of omega, is provided,
! according to the value of p%parms%aggr_omega_alg, specified by the user
! through amg_cprecinit and amg_zprecset.
!
! The coarse-level matrix A_C is distributed among the parallel processes or
! replicated on each of them, according to the value of p%parms%coarse_mat,
! specified by the user through amg_cprecinit and amg_zprecset.
! On output from this routine the entries of AC, op_prol, op_restr
! are still in "global numbering" mode; this is fixed in the calling routine
! aggregator%mat_bld.
!
!
! Arguments:
! a - type(psb_cspmat_type), input.
! The sparse matrix structure containing the local part of
! the fine-level matrix.
! desc_a - type(psb_desc_type), input.
! The communication descriptor of the fine-level matrix.
! p - type(amg_c_onelev_type), input/output.
! The 'one-level' data structure that will contain the local
! part of the matrix to be built as well as the information
! concerning the prolongator and its transpose.
! parms - type(amg_sml_parms), input
! Parameters controlling the choice of algorithm
! ac - type(psb_cspmat_type), output
! The coarse matrix on output
!
! ilaggr - integer, dimension(:), input
! The mapping between the row indices of the coarse-level
! matrix and the row indices of the fine-level matrix.
! ilaggr(i)=j means that node i in the adjacency graph
! of the fine-level matrix is mapped onto node j in the
! adjacency graph of the coarse-level matrix. Note that the indices
! are assumed to be shifted so as to make sure the ranges on
! the various processes do not overlap.
! nlaggr - integer, dimension(:) input
! nlaggr(i) contains the aggregates held by process i.
! op_prol - type(psb_cspmat_type), input/output
! The tentative prolongator on input, the computed prolongator on output
!
! op_restr - type(psb_cspmat_type), output
! The restrictor operator; normally, it is the transpose of the prolongator.
!
! info - integer, output.
! Error code.
!
subroutine amg_caggrmat_smth_bld(a,desc_a,ilaggr,nlaggr,parms,&
& ac,desc_ac,op_prol,op_restr,t_prol,info)
use psb_base_mod
use amg_base_prec_type
use amg_c_inner_mod, amg_protect_name => amg_caggrmat_smth_bld
use amg_c_base_aggregator_mod
implicit none
! Arguments
type(psb_cspmat_type), intent(in) :: a
type(psb_desc_type), intent(inout) :: desc_a
integer(psb_lpk_), intent(inout) :: ilaggr(:), nlaggr(:)
type(amg_sml_parms), intent(inout) :: parms
type(psb_cspmat_type), intent(inout) :: op_prol,ac,op_restr
type(psb_lcspmat_type), intent(inout) :: t_prol
type(psb_desc_type), intent(inout) :: desc_ac
integer(psb_ipk_), intent(out) :: info
! Local variables
integer(psb_lpk_) :: nrow, nglob, ncol, ntaggr, ip, &
& naggr, nzl,naggrm1,naggrp1, i, j, k, jd, icolF, nrw
integer(psb_ipk_) :: inaggr, nzlp
type(psb_ctxt_type) :: ctxt
integer(psb_ipk_) :: np, me
character(len=20) :: name
type(psb_lc_coo_sparse_mat) :: tmpcoo
type(psb_c_coo_sparse_mat) :: coo_prol, coo_restr
type(psb_c_csr_sparse_mat) :: acsr1, acsrf, csr_prol, acsr
complex(psb_spk_), allocatable :: adiag(:)
real(psb_spk_), allocatable :: arwsum(:)
integer(psb_ipk_) :: ierr(5)
logical :: filter_mat
integer(psb_ipk_) :: debug_level, debug_unit, err_act
integer(psb_ipk_), parameter :: ncmax=16
real(psb_spk_) :: anorm, omega, tmp, dg, theta
logical, parameter :: debug_new=.false.
character(len=80) :: filename
logical, parameter :: do_timings=.false.
integer(psb_ipk_), save :: idx_spspmm=-1, idx_phase1=-1, idx_gtrans=-1, idx_phase2=-1, idx_refine=-1
integer(psb_ipk_), save :: idx_phase3=-1, idx_cdasb=-1, idx_ptap=-1
name='amg_aggrmat_smth_bld'
info=psb_success_
call psb_erractionsave(err_act)
if (psb_errstatus_fatal()) then
info = psb_err_internal_error_; goto 9999
end if
debug_unit = psb_get_debug_unit()
debug_level = psb_get_debug_level()
ctxt = desc_a%get_context()
call psb_info(ctxt, me, np)
if ((do_timings).and.(idx_spspmm==-1)) &
& idx_spspmm = psb_get_timer_idx("DEC_SMTH_BLD: par_spspmm")
if ((do_timings).and.(idx_phase1==-1)) &
& idx_phase1 = psb_get_timer_idx("DEC_SMTH_BLD: phase1 ")
if ((do_timings).and.(idx_phase2==-1)) &
& idx_phase2 = psb_get_timer_idx("DEC_SMTH_BLD: phase2 ")
if ((do_timings).and.(idx_phase3==-1)) &
& idx_phase3 = psb_get_timer_idx("DEC_SMTH_BLD: phase3 ")
if ((do_timings).and.(idx_gtrans==-1)) &
& idx_gtrans = psb_get_timer_idx("DEC_SMTH_BLD: gtrans ")
if ((do_timings).and.(idx_refine==-1)) &
& idx_refine = psb_get_timer_idx("DEC_SMTH_BLD: refine ")
if ((do_timings).and.(idx_cdasb==-1)) &
& idx_cdasb = psb_get_timer_idx("DEC_SMTH_BLD: cdasb ")
if ((do_timings).and.(idx_ptap==-1)) &
& idx_ptap = psb_get_timer_idx("DEC_SMTH_BLD: ptap_bld ")
nglob = desc_a%get_global_rows()
nrow = desc_a%get_local_rows()
ncol = desc_a%get_local_cols()
theta = parms%aggr_thresh
naggr = nlaggr(me+1)
ntaggr = sum(nlaggr)
naggrm1 = sum(nlaggr(1:me))
naggrp1 = sum(nlaggr(1:me+1))
filter_mat = (parms%aggr_filter == amg_filter_mat_)
!
! naggr: number of local aggregates
! nrow: local rows.
!
if (do_timings) call psb_tic(idx_phase1)
! Get the diagonal D
adiag = a%get_diag(info)
if (info == psb_success_) &
& call psb_realloc(ncol,adiag,info)
if (info == psb_success_) &
& call psb_halo(adiag,desc_a,info)
if (info == psb_success_) call a%cp_to(acsr)
if(info /= psb_success_) then
call psb_errpush(psb_err_from_subroutine_,name,a_err='sp_getdiag')
goto 9999
end if
if (debug_level >= psb_debug_outer_) &
& write(debug_unit,*) me,' ',trim(name),&
& ' Initial copies done.'
call acsr%cp_to_fmt(acsrf,info)
if (filter_mat) then
!
! Build the filtered matrix Af from A
!
!$OMP parallel do private(i,j,tmp,jd) schedule(static)
do i=1, nrow
tmp = czero
jd = -1
do j=acsrf%irp(i),acsrf%irp(i+1)-1
if (acsrf%ja(j) == i) jd = j
if (abs(acsrf%val(j)) < theta*sqrt(abs(adiag(i)*adiag(acsrf%ja(j))))) then
tmp=tmp+acsrf%val(j)
acsrf%val(j)=czero
endif
enddo
if (jd == -1) then
write(0,*) 'Wrong input: we need the diagonal!!!!', i
else
acsrf%val(jd)=acsrf%val(jd)-tmp
end if
enddo
!$OMP end parallel do
! Take out zeroed terms
call acsrf%clean_zeros(info)
end if
!$OMP parallel do private(i) schedule(static)
do i=1,size(adiag)
if (adiag(i) /= czero) then
adiag(i) = cone / adiag(i)
else
adiag(i) = cone
end if
end do
!$OMP end parallel do
if (parms%aggr_omega_alg == amg_eig_est_) then
if (parms%aggr_eig == amg_max_norm_) then
allocate(arwsum(nrow))
call acsr%arwsum(arwsum)
anorm = maxval(abs(adiag(1:nrow)*arwsum(1:nrow)))
call psb_amx(ctxt,anorm)
omega = 4.d0/(3.d0*anorm)
parms%aggr_omega_val = omega
else
info = psb_err_internal_error_
call psb_errpush(info,name,a_err='invalid amg_aggr_eig_')
goto 9999
end if
else if (parms%aggr_omega_alg == amg_user_choice_) then
omega = parms%aggr_omega_val
else if (parms%aggr_omega_alg /= amg_user_choice_) then
info = psb_err_internal_error_
call psb_errpush(info,name,a_err='invalid amg_aggr_omega_alg_')
goto 9999
end if
if (do_timings) call psb_toc(idx_phase1)
if (do_timings) call psb_tic(idx_phase2)
call acsrf%scal(adiag,info)
if (info /= psb_success_) goto 9999
call t_prol%mv_to(tmpcoo)
inaggr = naggr
call psb_cdall(ctxt,desc_ac,info,nl=inaggr)
nzlp = tmpcoo%get_nzeros()
call desc_ac%indxmap%g2lip_ins(tmpcoo%ja(1:nzlp),info)
call tmpcoo%set_ncols(desc_ac%get_local_cols())
call tmpcoo%mv_to_ifmt(csr_prol,info)
call psb_cdasb(desc_ac,info)
call psb_cd_reinit(desc_ac,info)
if (do_timings) call psb_toc(idx_phase2)
if (do_timings) call psb_tic(idx_phase3)
!
! Build the smoothed prolongator using either A or Af
! acsr1 = (I-w*D*A) Prol acsr1 = (I-w*D*Af) Prol
! This is always done through the variable acsrf which
! is a bit less readable, but saves space and one matrix copy
!
call omega_smooth(omega,acsrf)
call psb_par_spspmm(acsrf,desc_a,csr_prol,acsr1,desc_ac,info)
if(info /= psb_success_) then
call psb_errpush(psb_err_from_subroutine_,name,a_err='spspmm 1')
goto 9999
end if
if (do_timings) call psb_toc(idx_phase3)
if (do_timings) call psb_tic(idx_ptap)
if (debug_level >= psb_debug_outer_) &
& write(debug_unit,*) me,' ',trim(name),&
& 'Done SPSPMM 1'
nzl = acsr1%get_nzeros()
call acsr1%mv_to_coo(coo_prol,info)
call amg_ptap_bld(acsr,desc_a,nlaggr,parms,ac,&
& coo_prol,desc_ac,coo_restr,info)
call op_prol%mv_from(coo_prol)
call op_restr%mv_from(coo_restr)
if (do_timings) call psb_toc(idx_ptap)
if (debug_level >= psb_debug_outer_) &
& write(debug_unit,*) me,' ',trim(name),&
& 'Done smooth_aggregate '
call psb_erractionrestore(err_act)
return
9999 continue
call psb_errpush(info,name)
call psb_error_handler(err_act)
return
contains
subroutine omega_smooth(omega,acsr)
implicit none
real(psb_spk_),intent(in) :: omega
type(psb_c_csr_sparse_mat), intent(inout) :: acsr
!
integer(psb_lpk_) :: i,j
do i=1,acsr%get_nrows()
do j=acsr%irp(i),acsr%irp(i+1)-1
if (acsr%ja(j) == i) then
acsr%val(j) = cone - omega*acsr%val(j)
else
acsr%val(j) = - omega*acsr%val(j)
end if
end do
end do
end subroutine omega_smooth
end subroutine amg_caggrmat_smth_bld