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514 lines
19 KiB
Fortran
514 lines
19 KiB
Fortran
!
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!
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! AMG4PSBLAS version 1.0
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! Algebraic Multigrid Package
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! based on PSBLAS (Parallel Sparse BLAS version 3.7)
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!
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! (C) Copyright 2021
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!
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! Salvatore Filippone
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! Pasqua D'Ambra
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! Fabio Durastante
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!
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! Redistribution and use in source and binary forms, with or without
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! modification, are permitted provided that the following conditions
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! are met:
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! 1. Redistributions of source code must retain the above copyright
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! notice, this list of conditions and the following disclaimer.
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! 2. Redistributions in binary form must reproduce the above copyright
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! notice, this list of conditions, and the following disclaimer in the
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! documentation and/or other materials provided with the distribution.
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! 3. The name of the AMG4PSBLAS group or the names of its contributors may
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! not be used to endorse or promote products derived from this
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! software without specific written permission.
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!
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! THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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! ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
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! TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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! PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AMG4PSBLAS GROUP OR ITS CONTRIBUTORS
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! BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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! CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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! SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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! INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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! CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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! ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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! POSSIBILITY OF SUCH DAMAGE.
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!
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!
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!
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! The aggregator object hosts the aggregation method for building
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! the multilevel hierarchy.
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!
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module amg_s_base_aggregator_mod
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use amg_base_prec_type, only : amg_sml_parms, amg_saggr_data
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use psb_base_mod, only : psb_sspmat_type, psb_lsspmat_type, psb_s_vect_type, &
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& psb_s_base_vect_type, psb_slinmap_type, psb_spk_, &
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& psb_ls_csr_sparse_mat, psb_ls_coo_sparse_mat, &
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& psb_s_csr_sparse_mat, psb_s_coo_sparse_mat, &
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& psb_ipk_, psb_epk_, psb_lpk_, psb_desc_type, psb_i_base_vect_type, &
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& psb_erractionsave, psb_error_handler, psb_success_, psb_toupper
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!
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!
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!
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!> \class amg_s_base_aggregator_type
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!!
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!! It is the data type containing the basic interface definition for
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!! building a multigrid hierarchy by aggregation. The base object has no attributes,
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!! it is intended to be essentially an abstract type.
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!!
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!!
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!! type amg_s_base_aggregator_type
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!! end type
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!!
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!!
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!! Methods:
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!!
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!! bld_tprol - Build a tentative prolongator
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!!
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!! mat_bld - Build prolongator/restrictor and coarse matrix ac
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!!
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!! mat_asb - Convert prolongator/restrictor/coarse matrix
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!! and fix their descriptor(s)
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!!
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!! update_next - Transfer information to the next level; default is
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!! to do nothing, i.e. aggregators at different
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!! levels are independent.
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!!
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!! default - Apply defaults
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!! set_aggr_type - For aggregator that have internal options.
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!! fmt - Return a short string description
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!! descr - Print a more detailed description
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!!
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!! cseti, csetr, csetc - Set internal parameters, if any
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!
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type amg_s_base_aggregator_type
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! Do we want to purge explicit zeros when aggregating?
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logical :: do_clean_zeros
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contains
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procedure, pass(ag) :: bld_tprol => amg_s_base_aggregator_build_tprol
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procedure, pass(ag) :: mat_bld => amg_s_base_aggregator_mat_bld
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procedure, pass(ag) :: mat_asb => amg_s_base_aggregator_mat_asb
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procedure, pass(ag) :: bld_map => amg_s_base_aggregator_bld_map
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procedure, pass(ag) :: update_next => amg_s_base_aggregator_update_next
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procedure, pass(ag) :: clone => amg_s_base_aggregator_clone
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procedure, pass(ag) :: free => amg_s_base_aggregator_free
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procedure, pass(ag) :: default => amg_s_base_aggregator_default
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procedure, pass(ag) :: descr => amg_s_base_aggregator_descr
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procedure, pass(ag) :: sizeof => amg_s_base_aggregator_sizeof
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procedure, pass(ag) :: set_aggr_type => amg_s_base_aggregator_set_aggr_type
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procedure, nopass :: fmt => amg_s_base_aggregator_fmt
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procedure, pass(ag) :: cseti => amg_s_base_aggregator_cseti
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procedure, pass(ag) :: csetr => amg_s_base_aggregator_csetr
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procedure, pass(ag) :: csetc => amg_s_base_aggregator_csetc
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generic, public :: set => cseti, csetr, csetc
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procedure, nopass :: xt_desc => amg_s_base_aggregator_xt_desc
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end type amg_s_base_aggregator_type
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abstract interface
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subroutine amg_s_soc_map_bld(iorder,theta,clean_zeros,a,desc_a,nlaggr,ilaggr,info)
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import :: psb_sspmat_type, psb_desc_type, psb_spk_, psb_ipk_, psb_lpk_
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implicit none
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integer(psb_ipk_), intent(in) :: iorder
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logical, intent(in) :: clean_zeros
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type(psb_sspmat_type), intent(in) :: a
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type(psb_desc_type), intent(in) :: desc_a
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real(psb_spk_), intent(in) :: theta
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integer(psb_lpk_), allocatable, intent(out) :: ilaggr(:),nlaggr(:)
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integer(psb_ipk_), intent(out) :: info
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end subroutine amg_s_soc_map_bld
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end interface
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interface amg_ptap_bld
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subroutine amg_s_ptap_bld(a_csr,desc_a,nlaggr,parms,ac,&
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& coo_prol,desc_cprol,coo_restr,info,desc_ax)
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import :: psb_s_csr_sparse_mat, psb_sspmat_type, psb_desc_type, &
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& psb_s_coo_sparse_mat, amg_sml_parms, psb_spk_, psb_ipk_, psb_lpk_
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implicit none
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type(psb_s_csr_sparse_mat), intent(inout) :: a_csr
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type(psb_desc_type), intent(inout) :: desc_a
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integer(psb_lpk_), intent(inout) :: nlaggr(:)
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type(amg_sml_parms), intent(inout) :: parms
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type(psb_s_coo_sparse_mat), intent(inout) :: coo_prol, coo_restr
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type(psb_desc_type), intent(inout) :: desc_cprol
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type(psb_sspmat_type), intent(out) :: ac
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integer(psb_ipk_), intent(out) :: info
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type(psb_desc_type), intent(inout), optional :: desc_ax
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end subroutine amg_s_ptap_bld
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end interface amg_ptap_bld
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interface amg_rap
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subroutine amg_s_rap(a_csr,desc_a,nlaggr,parms,ac,&
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& coo_prol,desc_cprol,coo_restr,info)
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import :: psb_s_csr_sparse_mat, psb_sspmat_type, psb_desc_type, &
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& psb_s_coo_sparse_mat, amg_sml_parms, psb_spk_, psb_ipk_, psb_lpk_
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implicit none
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type(psb_s_csr_sparse_mat), intent(inout) :: a_csr
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type(psb_desc_type), intent(inout) :: desc_a
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integer(psb_lpk_), intent(inout) :: nlaggr(:)
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type(amg_sml_parms), intent(inout) :: parms
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type(psb_s_coo_sparse_mat), intent(inout) :: coo_prol, coo_restr
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type(psb_desc_type), intent(inout) :: desc_cprol
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type(psb_sspmat_type), intent(out) :: ac
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integer(psb_ipk_), intent(out) :: info
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end subroutine amg_s_rap
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end interface amg_rap
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contains
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subroutine amg_s_base_aggregator_cseti(ag,what,val,info,idx)
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Implicit None
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! Arguments
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class(amg_s_base_aggregator_type), intent(inout) :: ag
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character(len=*), intent(in) :: what
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integer(psb_ipk_), intent(in) :: val
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integer(psb_ipk_), intent(out) :: info
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integer(psb_ipk_), intent(in), optional :: idx
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! Do nothing
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info = 0
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end subroutine amg_s_base_aggregator_cseti
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subroutine amg_s_base_aggregator_csetr(ag,what,val,info,idx)
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Implicit None
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! Arguments
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class(amg_s_base_aggregator_type), intent(inout) :: ag
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character(len=*), intent(in) :: what
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real(psb_spk_), intent(in) :: val
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integer(psb_ipk_), intent(out) :: info
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integer(psb_ipk_), intent(in), optional :: idx
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! Do nothing
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info = 0
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end subroutine amg_s_base_aggregator_csetr
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subroutine amg_s_base_aggregator_csetc(ag,what,val,info,idx)
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Implicit None
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! Arguments
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class(amg_s_base_aggregator_type), intent(inout) :: ag
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character(len=*), intent(in) :: what
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character(len=*), intent(in) :: val
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integer(psb_ipk_), intent(out) :: info
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integer(psb_ipk_), intent(in), optional :: idx
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! Set clean zeros, or do nothing.
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select case (psb_toupper(trim(what)))
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case('AGGR_CLEAN_ZEROS')
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select case (psb_toupper(trim(val)))
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case('TRUE','T')
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ag%do_clean_zeros = .true.
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case('FALSE','F')
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ag%do_clean_zeros = .false.
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end select
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end select
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info = 0
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end subroutine amg_s_base_aggregator_csetc
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subroutine amg_s_base_aggregator_update_next(ag,agnext,info)
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implicit none
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class(amg_s_base_aggregator_type), target, intent(inout) :: ag, agnext
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integer(psb_ipk_), intent(out) :: info
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!
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! Base version does nothing.
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!
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info = 0
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end subroutine amg_s_base_aggregator_update_next
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subroutine amg_s_base_aggregator_clone(ag,agnext,info)
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implicit none
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class(amg_s_base_aggregator_type), intent(inout) :: ag
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class(amg_s_base_aggregator_type), allocatable, intent(inout) :: agnext
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integer(psb_ipk_), intent(out) :: info
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info = 0
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if (allocated(agnext)) then
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call agnext%free(info)
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if (info == 0) deallocate(agnext,stat=info)
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end if
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if (info /= 0) return
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allocate(agnext,source=ag,stat=info)
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end subroutine amg_s_base_aggregator_clone
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subroutine amg_s_base_aggregator_free(ag,info)
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implicit none
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class(amg_s_base_aggregator_type), intent(inout) :: ag
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integer(psb_ipk_), intent(out) :: info
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info = psb_success_
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return
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end subroutine amg_s_base_aggregator_free
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subroutine amg_s_base_aggregator_default(ag)
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implicit none
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class(amg_s_base_aggregator_type), intent(inout) :: ag
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! Only one default setting
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ag%do_clean_zeros = .true.
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return
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end subroutine amg_s_base_aggregator_default
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function amg_s_base_aggregator_fmt() result(val)
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implicit none
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character(len=32) :: val
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val = "Default aggregator "
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end function amg_s_base_aggregator_fmt
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function amg_s_base_aggregator_sizeof(ag) result(val)
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implicit none
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class(amg_s_base_aggregator_type), intent(in) :: ag
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integer(psb_epk_) :: val
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val = 1
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end function amg_s_base_aggregator_sizeof
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function amg_s_base_aggregator_xt_desc() result(val)
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implicit none
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logical :: val
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val = .false.
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end function amg_s_base_aggregator_xt_desc
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subroutine amg_s_base_aggregator_descr(ag,parms,iout,info,prefix)
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implicit none
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class(amg_s_base_aggregator_type), intent(in) :: ag
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type(amg_sml_parms), intent(in) :: parms
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integer(psb_ipk_), intent(in) :: iout
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integer(psb_ipk_), intent(out) :: info
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character(len=*), intent(in), optional :: prefix
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character(1024) :: prefix_
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if (present(prefix)) then
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prefix_ = prefix
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else
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prefix_ = ""
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end if
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write(iout,*) trim(prefix_),' ', 'Aggregator object type: ',ag%fmt()
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call parms%mldescr(iout,info,prefix=prefix)
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return
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end subroutine amg_s_base_aggregator_descr
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subroutine amg_s_base_aggregator_set_aggr_type(ag,parms,info)
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implicit none
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class(amg_s_base_aggregator_type), intent(inout) :: ag
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type(amg_sml_parms), intent(in) :: parms
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integer(psb_ipk_), intent(out) :: info
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! Do nothing
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return
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end subroutine amg_s_base_aggregator_set_aggr_type
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!
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!> Function bld_tprol:
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!! \memberof amg_s_base_aggregator_type
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!! \brief Build a tentative prolongator.
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!! The routine will map the local matrix entries to aggregates.
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!! The mapping is store in ILAGGR; for each local row index I,
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!! ILAGGR(I) contains the index of the aggregate to which index I
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!! will contribute, in global numbering.
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!! Many aggregations produce a binary tentative prolongator, but some
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!! do not, hence we also need the OP_PROL output.
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!! AG_DATA is passed here just in case some of the
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!! aggregators need it internally, most of them will ignore.
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!!
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!! \param ag The input aggregator object
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!! \param parms The auxiliary parameters object
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!! \param ag_data Auxiliary global aggregation info
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!! \param a The local matrix part
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!! \param desc_a The descriptor
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!! \param ilaggr Output aggregation map
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!! \param nlaggr Sizes of ilaggr on all processes
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!! \param op_prol The tentative prolongator operator
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!! \param info Return code
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!!
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!
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subroutine amg_s_base_aggregator_build_tprol(ag,parms,ag_data,&
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& a,desc_a,ilaggr,nlaggr,t_prol,info)
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use psb_base_mod
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implicit none
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class(amg_s_base_aggregator_type), target, intent(inout) :: ag
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type(amg_sml_parms), intent(inout) :: parms
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type(amg_saggr_data), intent(in) :: ag_data
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type(psb_sspmat_type), intent(inout) :: a
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type(psb_desc_type), intent(inout) :: desc_a
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integer(psb_lpk_), allocatable, intent(out) :: ilaggr(:),nlaggr(:)
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type(psb_lsspmat_type), intent(out) :: t_prol
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integer(psb_ipk_), intent(out) :: info
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integer(psb_ipk_) :: err_act
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character(len=20) :: name='s_base_aggregator_build_tprol'
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call psb_erractionsave(err_act)
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info = psb_err_missing_override_method_
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call psb_errpush(info,name)
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goto 9999
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call psb_erractionrestore(err_act)
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return
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9999 call psb_error_handler(err_act)
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return
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end subroutine amg_s_base_aggregator_build_tprol
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!
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!> Function mat_bld
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!! \memberof amg_s_base_aggregator_type
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!! \brief Build prolongator/restrictor/coarse matrix.
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!!
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!!
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!! \param ag The input aggregator object
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!! \param parms The auxiliary parameters object
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!! \param a The local matrix part
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!! \param desc_a The descriptor
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!! \param ilaggr Aggregation map
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!! \param nlaggr Sizes of ilaggr on all processes
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!! \param ac On output the coarse matrix
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!! \param op_prol On input, the tentative prolongator operator, on output
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!! the final prolongator
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!! \param op_restr On output, the restrictor operator;
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!! in many cases it is the transpose of the prolongator.
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!! \param info Return code
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!!
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subroutine amg_s_base_aggregator_mat_bld(ag,parms,a,desc_a,ilaggr,nlaggr,&
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& ac,desc_ac,op_prol,op_restr,t_prol,info)
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use psb_base_mod
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implicit none
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class(amg_s_base_aggregator_type), target, intent(inout) :: ag
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type(amg_sml_parms), intent(inout) :: parms
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type(psb_sspmat_type), intent(in) :: a
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type(psb_desc_type), intent(inout) :: desc_a
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integer(psb_lpk_), intent(inout) :: ilaggr(:), nlaggr(:)
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type(psb_lsspmat_type), intent(inout) :: t_prol
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type(psb_sspmat_type), intent(out) :: op_prol, ac,op_restr
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type(psb_desc_type), intent(inout) :: desc_ac
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integer(psb_ipk_), intent(out) :: info
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integer(psb_ipk_) :: err_act
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character(len=20) :: name='s_base_aggregator_mat_bld'
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call psb_erractionsave(err_act)
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info = psb_err_missing_override_method_
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call psb_errpush(info,name)
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goto 9999
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call psb_erractionrestore(err_act)
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return
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9999 call psb_error_handler(err_act)
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return
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end subroutine amg_s_base_aggregator_mat_bld
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!
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!> Function mat_asb
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!! \memberof amg_s_base_aggregator_type
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!! \brief Build prolongator/restrictor/coarse matrix.
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!!
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!!
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!! \param ag The input aggregator object
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!! \param parms The auxiliary parameters object
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!! \param a The local matrix part
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!! \param desc_a The descriptor
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!! \param ilaggr Aggregation map
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!! \param nlaggr Sizes of ilaggr on all processes
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!! \param ac On output the coarse matrix
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!! \param op_prol On input, the tentative prolongator operator, on output
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!! the final prolongator
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!! \param op_restr On output, the restrictor operator;
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!! in many cases it is the transpose of the prolongator.
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!! \param info Return code
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|
!!
|
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subroutine amg_s_base_aggregator_mat_asb(ag,parms,a,desc_a,&
|
|
& ac,desc_ac, op_prol,op_restr,info)
|
|
use psb_base_mod
|
|
implicit none
|
|
class(amg_s_base_aggregator_type), target, intent(inout) :: ag
|
|
type(amg_sml_parms), intent(inout) :: parms
|
|
type(psb_sspmat_type), intent(in) :: a
|
|
type(psb_desc_type), intent(inout) :: desc_a
|
|
type(psb_sspmat_type), intent(inout) :: op_prol,ac,op_restr
|
|
type(psb_desc_type), intent(inout) :: desc_ac
|
|
integer(psb_ipk_), intent(out) :: info
|
|
integer(psb_ipk_) :: err_act
|
|
character(len=20) :: name='s_base_aggregator_mat_asb'
|
|
|
|
call psb_erractionsave(err_act)
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|
|
|
info = psb_err_missing_override_method_
|
|
call psb_errpush(info,name)
|
|
goto 9999
|
|
|
|
call psb_erractionrestore(err_act)
|
|
return
|
|
|
|
9999 call psb_error_handler(err_act)
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|
|
|
return
|
|
end subroutine amg_s_base_aggregator_mat_asb
|
|
|
|
!
|
|
!> Function bld_map
|
|
!! \memberof amg_s_base_aggregator_type
|
|
!! \brief Build linear map between hierarchy levels
|
|
!!
|
|
!!
|
|
!! \param ag The input aggregator object
|
|
!! \param desc_a The fine space descriptor
|
|
!! \param desc_ac The coarse space descriptor
|
|
!! \param ilaggr Aggregation map vector
|
|
!! \param nlaggr Sizes of ilaggr on all processes
|
|
!! \param op_prol The prolongator operator
|
|
!! \param op_restr The restrictor operator
|
|
!! \param map The output map
|
|
!! \param info Return code
|
|
!!
|
|
subroutine amg_s_base_aggregator_bld_map(ag,desc_a,desc_ac,ilaggr,nlaggr,&
|
|
& op_restr,op_prol,map,info)
|
|
use psb_base_mod
|
|
implicit none
|
|
class(amg_s_base_aggregator_type), target, intent(inout) :: ag
|
|
type(psb_desc_type), intent(in), target :: desc_a, desc_ac
|
|
integer(psb_lpk_), intent(inout) :: ilaggr(:), nlaggr(:)
|
|
type(psb_sspmat_type), intent(inout) :: op_restr, op_prol
|
|
type(psb_slinmap_type), intent(out) :: map
|
|
integer(psb_ipk_), intent(out) :: info
|
|
integer(psb_ipk_) :: err_act
|
|
character(len=20) :: name='s_base_aggregator_bld_map'
|
|
|
|
call psb_erractionsave(err_act)
|
|
!
|
|
! Copy the prolongation/restriction matrices into the descriptor map.
|
|
! op_restr => PR^T i.e. restriction operator
|
|
! op_prol => PR i.e. prolongation operator
|
|
!
|
|
! WARNING: need to check whether the copy into IOP_RESTR/IOP_PROL
|
|
! is safe or not.
|
|
!
|
|
! This default implementation reuses desc_a/desc_ac through
|
|
! pointers in the map structure.
|
|
!
|
|
map = psb_linmap(psb_map_aggr_,desc_a,&
|
|
& desc_ac,op_restr,op_prol,ilaggr,nlaggr)
|
|
|
|
call psb_erractionrestore(err_act)
|
|
return
|
|
|
|
9999 call psb_error_handler(err_act)
|
|
|
|
return
|
|
end subroutine amg_s_base_aggregator_bld_map
|
|
|
|
|
|
end module amg_s_base_aggregator_mod
|