! ! ! MLD2P4 version 2.2 ! MultiLevel Domain Decomposition Parallel Preconditioners Package ! based on PSBLAS (Parallel Sparse BLAS version 3.5) ! ! (C) Copyright 2008-2018 ! ! Salvatore Filippone ! Pasqua D'Ambra ! Daniela di Serafino ! ! 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_daggrmat_nosmth_bld.F90 ! ! Subroutine: mld_daggrmat_nosmth_bld ! Version: real ! ! 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 the piecewise constant interpolation operator corresponding ! the fine-to-coarse level mapping built by mld_aggrmap_bld. ! ! 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 mld_dprecinit and mld_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. ! ! For details see ! P. D'Ambra, D. di Serafino and S. Filippone, On the development of ! PSBLAS-based parallel two-level Schwarz preconditioners, Appl. Num. Math., ! 57 (2007), 1181-1196. ! ! ! Arguments: ! a - type(psb_dspmat_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(mld_d_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(mld_dml_parms), input ! Parameters controlling the choice of algorithm ! ac - type(psb_dspmat_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_dspmat_type), input/output ! The tentative prolongator on input, the computed prolongator on output ! ! op_restr - type(psb_dspmat_type), output ! The restrictor operator; normally, it is the transpose of the prolongator. ! ! info - integer, output. ! Error code. ! ! subroutine mld_daggrmat_nosmth_bld(a,desc_a,ilaggr,nlaggr,parms,ac,op_prol,op_restr,info) use psb_base_mod use mld_base_prec_type use mld_d_inner_mod, mld_protect_name => mld_daggrmat_nosmth_bld implicit none ! Arguments type(psb_dspmat_type), intent(in) :: a type(psb_desc_type), intent(in) :: desc_a integer(psb_lpk_), intent(inout) :: ilaggr(:), nlaggr(:) type(mld_dml_parms), intent(inout) :: parms type(psb_ldspmat_type), intent(inout) :: op_prol type(psb_ldspmat_type), intent(out) :: ac,op_restr integer(psb_ipk_), intent(out) :: info ! Local variables integer(psb_ipk_) :: err_act integer(psb_ipk_) :: ictxt, np, me, icomm, minfo character(len=20) :: name integer(psb_ipk_) :: ierr(5) type(psb_ldspmat_type) :: la type(psb_ld_coo_sparse_mat) :: ac_coo, tmpcoo type(psb_ld_csr_sparse_mat) :: acsr1, acsr2 integer(psb_ipk_) :: debug_level, debug_unit integer(psb_lpk_) :: nrow, nglob, ncol, ntaggr, nzl, ip, & & naggr, nzt, naggrm1, naggrp1, i, k name = 'mld_aggrmat_nosmth_bld' info = psb_success_ call psb_erractionsave(err_act) if (psb_errstatus_fatal()) then info = psb_err_internal_error_; goto 9999 end if ictxt = desc_a%get_context() icomm = desc_a%get_mpic() call psb_info(ictxt, me, np) nglob = desc_a%get_global_rows() nrow = desc_a%get_local_rows() ncol = desc_a%get_local_cols() naggr = nlaggr(me+1) ntaggr = sum(nlaggr) naggrm1 = sum(nlaggr(1:me)) naggrp1 = sum(nlaggr(1:me+1)) call op_prol%cp_to(tmpcoo) call op_prol%cscnv(info,type='csr',dupl=psb_dupl_add_) call tmpcoo%transp() ! ! Now we have to fix this. The only rows of tmpcoo/op_restr that are correct ! are those corresponding to "local" aggregates, i.e. indices in ilaggr(:) ! nzl = tmpcoo%get_nzeros() i = 0 do k = 1, nzl if ((naggrm1 < tmpcoo%ia(k)) .and.(tmpcoo%ia(k) <= naggrp1)) then i = i+1 tmpcoo%val(i) = tmpcoo%val(k) tmpcoo%ia(i) = tmpcoo%ia(k) tmpcoo%ja(i) = tmpcoo%ja(k) end if end do call tmpcoo%set_nzeros(i) ! call tmpcoo%trim() call op_restr%mv_from(tmpcoo) call op_restr%cscnv(info,type='csr',dupl=psb_dupl_add_) if (info /= psb_success_) goto 9999 call a%cp_to(ac_coo) nzt = ac_coo%get_nzeros() k = 0 do i = 1, nzt k = k + 1 ac_coo%ia(k) = ilaggr(ac_coo%ia(i)) ac_coo%ja(k) = ilaggr(ac_coo%ja(i)) ac_coo%val(k) = ac_coo%val(i) ! At this point, there may be negative entries, ! because that's how ILAGGR marks singletons ! If this is the case, roll back K if ((ac_coo%ia(k)<=0).or.(ac_coo%ja(k)<=0)) k = k-1 enddo call ac_coo%set_nrows(naggr) call ac_coo%set_ncols(naggr) call ac_coo%set_nzeros(k) call ac_coo%set_dupl(psb_dupl_add_) call ac_coo%fix(info) call ac_coo%trim() call ac%mv_from(ac_coo) call psb_erractionrestore(err_act) return 9999 call psb_error_handler(err_act) return end subroutine mld_daggrmat_nosmth_bld