! ! Parallel Sparse BLAS version 3.5 ! (C) Copyright 2006-2018 ! Salvatore Filippone ! Alfredo Buttari ! ! 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 PSBLAS group or the names of its contributors may ! not be used to endorse or promote products derived from this ! software without specific prior 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 PSBLAS 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: psb_d_nest_prec_cg_test.F90 ! ! Program: psb_d_nest_prec_cg_test ! ! Same matrix/RHS/CG check as psb_d_nest_cg_test, but the preconditioner is the ! specialized nested preconditioner: ! ! call preconditioner%init(context, 'NEST', info) ! call preconditioner%set('COMPOSITION', 'ADDITIVE', info) ! call preconditioner%set('BLOCK_SOLVE', 'DIAG', info) ! ! The matrix is the red-black reordered 1D Laplacian: ! ! M = [ 2I C ] ! [ C^T 2I ] ! ! With diagonal block solves this NEST/ADDITIVE preconditioner is a scalar ! rescaling of the identity on this problem, so CG should converge to the exact ! solution and reproduce the unpreconditioned iteration count. ! program psb_d_nest_prec_cg_test use psb_base_mod use psb_util_mod use psb_prec_mod use psb_linsolve_mod use psb_d_nest_mod implicit none type(psb_ctxt_type) :: context integer(psb_ipk_) :: my_rank, num_procs, info, i_local_row, entry_idx integer(psb_ipk_) :: field1_local_rows, field2_local_rows integer(psb_lpk_) :: field1_global_row, field2_global_row, field_size type(psb_d_nest_matrix) :: nested_matrix type(psb_dprec_type) :: preconditioner type(psb_d_vect_type) :: x_solution, rhs, x_exact integer(psb_lpk_), allocatable :: entry_rows(:), entry_cols(:) integer(psb_lpk_), allocatable :: field1_rows(:), field2_rows(:) real(psb_dpk_), allocatable :: entry_vals(:) real(psb_dpk_) :: diag_value, stop_tol, final_residual real(psb_dpk_) :: norm_x_exact, solution_error integer(psb_ipk_) :: max_iter, trace_level, n_iter, n_iter_none integer(psb_ipk_) :: stop_criterion real(psb_dpk_), parameter :: solution_tol = 1.0e-6_psb_dpk_ logical :: all_passed call psb_init(context) call psb_info(context, my_rank, num_procs) field_size = 512 diag_value = 2.0_psb_dpk_ stop_tol = 1.0e-9_psb_dpk_ max_iter = 4000 trace_level = 0 stop_criterion = 2 all_passed = .true. call nested_matrix%init(context, [field_size, field_size], info) if (info /= psb_success_) then if (my_rank == 0) write(*,*) 'FAIL: nested_matrix%init info=', info goto 9999 end if field1_rows = nested_matrix%get_owned_rows(1) field2_rows = nested_matrix%get_owned_rows(2) field1_local_rows = size(field1_rows) field2_local_rows = size(field2_rows) ! block (1,1) = diag*I allocate(entry_rows(field1_local_rows), entry_cols(field1_local_rows), entry_vals(field1_local_rows)) do i_local_row = 1, field1_local_rows field1_global_row = field1_rows(i_local_row) entry_rows(i_local_row) = field1_global_row entry_cols(i_local_row) = field1_global_row entry_vals(i_local_row) = diag_value end do call nested_matrix%ins(1, 1, field1_local_rows, entry_rows, entry_cols, entry_vals, info) deallocate(entry_rows, entry_cols, entry_vals) ! block (2,2) = diag*I allocate(entry_rows(field2_local_rows), entry_cols(field2_local_rows), entry_vals(field2_local_rows)) do i_local_row = 1, field2_local_rows field2_global_row = field2_rows(i_local_row) entry_rows(i_local_row) = field2_global_row entry_cols(i_local_row) = field2_global_row entry_vals(i_local_row) = diag_value end do call nested_matrix%ins(2, 2, field2_local_rows, entry_rows, entry_cols, entry_vals, info) deallocate(entry_rows, entry_cols, entry_vals) ! block (1,2) = C allocate(entry_rows(2*field1_local_rows), entry_cols(2*field1_local_rows), entry_vals(2*field1_local_rows)) entry_idx = 0 do i_local_row = 1, field1_local_rows field1_global_row = field1_rows(i_local_row) entry_idx = entry_idx + 1 entry_rows(entry_idx) = field1_global_row entry_cols(entry_idx) = field1_global_row entry_vals(entry_idx) = -1.0_psb_dpk_ if (field1_global_row > 1) then entry_idx = entry_idx + 1 entry_rows(entry_idx) = field1_global_row entry_cols(entry_idx) = field1_global_row - 1_psb_lpk_ entry_vals(entry_idx) = -1.0_psb_dpk_ end if end do call nested_matrix%ins(1, 2, entry_idx, entry_rows, entry_cols, entry_vals, info) deallocate(entry_rows, entry_cols, entry_vals) ! block (2,1) = C^T allocate(entry_rows(2*field2_local_rows), entry_cols(2*field2_local_rows), entry_vals(2*field2_local_rows)) entry_idx = 0 do i_local_row = 1, field2_local_rows field2_global_row = field2_rows(i_local_row) entry_idx = entry_idx + 1 entry_rows(entry_idx) = field2_global_row entry_cols(entry_idx) = field2_global_row entry_vals(entry_idx) = -1.0_psb_dpk_ if (field2_global_row < field_size) then entry_idx = entry_idx + 1 entry_rows(entry_idx) = field2_global_row entry_cols(entry_idx) = field2_global_row + 1_psb_lpk_ entry_vals(entry_idx) = -1.0_psb_dpk_ end if end do call nested_matrix%ins(2, 1, entry_idx, entry_rows, entry_cols, entry_vals, info) deallocate(entry_rows, entry_cols, entry_vals) call nested_matrix%asb(info) if (info /= psb_success_) then if (my_rank == 0) write(*,*) 'FAIL: nested_matrix%asb info=', info goto 9999 end if call psb_geall(x_exact, nested_matrix%desc_glob, info) call psb_geasb(x_exact, nested_matrix%desc_glob, info) call x_exact%set(done) call psb_geall(rhs, nested_matrix%desc_glob, info) call psb_geasb(rhs, nested_matrix%desc_glob, info) call psb_spmm(done, nested_matrix%a_glob, x_exact, dzero, rhs, nested_matrix%desc_glob, info) if (info /= psb_success_) then if (my_rank == 0) write(*,*) 'FAIL: psb_spmm (RHS) info=', info goto 9999 end if norm_x_exact = psb_genrm2(x_exact, nested_matrix%desc_glob, info) if (my_rank == 0) write(*,'(a,i0,a,i0)') ' np=', num_procs, ' N(global)=', 2*field_size ! Baseline: no preconditioner. call preconditioner%init(context, 'NONE', info) call preconditioner%build(nested_matrix%a_glob, nested_matrix%desc_glob, info) call psb_geall(x_solution, nested_matrix%desc_glob, info) call psb_geasb(x_solution, nested_matrix%desc_glob, info) call psb_krylov('CG', nested_matrix%a_glob, preconditioner, rhs, x_solution, stop_tol, & & nested_matrix%desc_glob, info, & & itmax=max_iter, iter=n_iter_none, err=final_residual, itrace=trace_level, istop=stop_criterion) if (info /= psb_success_) then if (my_rank == 0) write(*,*) 'FAIL: psb_krylov(CG,NONE) info=', info all_passed = .false. end if if (my_rank == 0) write(*,'(a,i6,a,es12.4)') & & ' prec=NONE CG iterations=', n_iter_none, ' residual=', final_residual call psb_gefree(x_solution, nested_matrix%desc_glob, info) call preconditioner%free(info) ! Specialized nested preconditioner: additive block-diagonal field split. call preconditioner%init(context, 'NEST', info) call preconditioner%set('COMPOSITION', 'ADDITIVE', info) call preconditioner%set('BLOCK_SOLVE', 'DIAG', info) call preconditioner%build(nested_matrix%a_glob, nested_matrix%desc_glob, info) if (info /= psb_success_) then if (my_rank == 0) write(*,*) 'FAIL: nested prec%build info=', info all_passed = .false. goto 9999 end if call psb_geall(x_solution, nested_matrix%desc_glob, info) call psb_geasb(x_solution, nested_matrix%desc_glob, info) call psb_krylov('CG', nested_matrix%a_glob, preconditioner, rhs, x_solution, stop_tol, & & nested_matrix%desc_glob, info, & & itmax=max_iter, iter=n_iter, err=final_residual, itrace=trace_level, istop=stop_criterion) if (info /= psb_success_) then if (my_rank == 0) write(*,*) 'FAIL: psb_krylov(CG,NEST) info=', info all_passed = .false. end if call psb_geaxpby(-done, x_exact, done, x_solution, nested_matrix%desc_glob, info) solution_error = psb_genrm2(x_solution, nested_matrix%desc_glob, info) / norm_x_exact if (my_rank == 0) then write(*,'(a,i6,a,es12.4,a,es12.4)') & & ' prec=NEST CG iterations=', n_iter, ' residual=', final_residual, & & ' ||x-x_ex||/||x_ex||=', solution_error end if if ((n_iter >= max_iter) .or. (solution_error > solution_tol)) all_passed = .false. if (n_iter /= n_iter_none) all_passed = .false. if (my_rank == 0) then if (all_passed) then write(*,*) '[PASS] CG converges with the specialized NEST preconditioner' else write(*,*) '[FAIL] CG with specialized NEST preconditioner' end if end if call psb_gefree(x_solution, nested_matrix%desc_glob, info) call preconditioner%free(info) call nested_matrix%free(info) 9999 continue call psb_exit(context) end program psb_d_nest_prec_cg_test