Taken out diagl/diagu, no longer used.
First draft of a complex RGMRES.psblas3-type-indexed
Salvatore Filippone
18 years ago
parent
028c2f2c96
commit
82c7ef87bd
@ -0,0 +1,574 @@
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!!$
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!!$ Parallel Sparse BLAS v2.0
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!!$ (C) Copyright 2006 Salvatore Filippone University of Rome Tor Vergata
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!!$ Alfredo Buttari University of Rome Tor Vergata
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!!$
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!!$ Contributions to this routine:
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!!$ Daniela di Serafino Second University of Naples
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!!$ Pasqua D'Ambra ICAR-CNR
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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 PSBLAS 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 PSBLAS 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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!!$ CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
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!!$ C C
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!!$ C References: C
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!!$ C [1] Duff, I., Marrone, M., Radicati, G., and Vittoli, C. C
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!!$ C Level 3 basic linear algebra subprograms for sparse C
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!!$ C matrices: a user level interface C
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!!$ C ACM Trans. Math. Softw., 23(3), 379-401, 1997. C
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!!$ C C
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!!$ C C
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!!$ C [2] S. Filippone, M. Colajanni C
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!!$ C PSBLAS: A library for parallel linear algebra C
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!!$ C computation on sparse matrices C
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!!$ C ACM Trans. on Math. Softw., 26(4), 527-550, Dec. 2000. C
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!!$ C C
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!!$ C [3] M. Arioli, I. Duff, M. Ruiz C
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!!$ C Stopping criteria for iterative solvers C
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!!$ C SIAM J. Matrix Anal. Appl., Vol. 13, pp. 138-144, 1992 C
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!!$ C C
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!!$ C C
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!!$ C [4] R. Barrett et al C
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!!$ C Templates for the solution of linear systems C
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!!$ C SIAM, 1993 C
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!!$ C C
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!!$ C C
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!!$ C [5] G. Sleijpen, D. Fokkema C
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!!$ C BICGSTAB(L) for linear equations involving unsymmetric C
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!!$ C matrices with complex spectrum C
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!!$ C Electronic Trans. on Numer. Analysis, Vol. 1, pp. 11-32, C
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!!$ C Sep. 1993 C
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!!$ C C
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!!$ C C
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!!$ CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
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! File: psb_dgmresr.f90
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!
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! Subroutine: psb_dgmres
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! This subroutine implements the restarted GMRES method with right
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! preconditioning.
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!
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! Parameters:
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! a - type(<psb_dspmat_type>). The sparse matrix containing A.
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! prec - type(<psb_prec_type>). The data structure containing the preconditioner.
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! b - real,dimension(:). The right hand side.
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! x - real,dimension(:). The vector of unknowns.
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! eps - real. The error tolerance.
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! desc_a - type(<psb_desc_type>). The communication descriptor.
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! info - integer. Eventually returns an error code.
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! itmax - integer(optional). The maximum number of iterations.
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! iter - integer(optional). The number of iterations performed.
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! err - real(optional). The error on return.
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! itrace - integer(optional). The unit to write messages onto.
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! irst - integer(optional). The restart value.
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! istop - integer(optional). The stopping criterium.
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!
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Subroutine psb_zgmresr(a,prec,b,x,eps,desc_a,info,&
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& itmax,iter,err,itrace,irst,istop)
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use psb_base_mod
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use psb_prec_mod
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implicit none
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!!$ Parameters
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Type(psb_zspmat_type), Intent(in) :: a
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Type(psb_zprec_type), Intent(in) :: prec
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Type(psb_desc_type), Intent(in) :: desc_a
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complex(Kind(1.d0)), Intent(in) :: b(:)
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complex(Kind(1.d0)), Intent(inout) :: x(:)
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Real(Kind(1.d0)), Intent(in) :: eps
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integer, intent(out) :: info
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Integer, Optional, Intent(in) :: itmax, itrace, irst,istop
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Integer, Optional, Intent(out) :: iter
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Real(Kind(1.d0)), Optional, Intent(out) :: err
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!!$ local data
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complex(Kind(1.d0)), allocatable, target :: aux(:),w(:),w1(:), v(:,:)
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complex(Kind(1.d0)), allocatable :: c(:),s(:), h(:,:), rs(:),rst(:),xt(:)
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Real(Kind(1.d0)) :: rerr, gm,tmp
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complex(kind(1.d0)) :: rti, rti1, scal
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Integer ::litmax, liter, naux, m, mglob, it,k, itrace_,&
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& np,me, n_row, n_col, nl, int_err(5)
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Logical, Parameter :: exchange=.True., noexchange=.False.
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Integer, Parameter :: irmax = 8
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Integer :: itx, i, isvch, ich, ictxt,istop_, err_act
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Logical, Parameter :: debug = .false.
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Real(Kind(1.d0)) :: rni, xni, bni, ani,bn2, dt
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real(kind(1.d0)), external :: dznrm2
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character(len=20) :: name
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info = 0
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name = 'psb_dgmres'
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call psb_erractionsave(err_act)
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If (debug) Write(0,*) 'entering psb_dgmres'
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ictxt = psb_cd_get_context(desc_a)
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Call psb_info(ictxt, me, np)
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If (debug) Write(0,*) 'psb_dgmres: from gridinfo',np,me
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mglob = psb_cd_get_global_rows(desc_a)
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n_row = psb_cd_get_local_rows(desc_a)
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n_col = psb_cd_get_local_cols(desc_a)
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if (present(istop)) then
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istop_ = istop
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else
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istop_ = 1
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endif
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!
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! ISTOP_ = 1: Normwise backward error, infinity norm
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! ISTOP_ = 2: ||r||/||b||, 2-norm
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!
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if ((istop_ < 1 ).or.(istop_ > 2 ) ) then
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write(0,*) 'psb_dgmres: invalid istop',istop_
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info=5001
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int_err(1)=istop_
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err=info
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call psb_errpush(info,name,i_err=int_err)
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goto 9999
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endif
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If (Present(itmax)) Then
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litmax = itmax
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Else
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litmax = 1000
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Endif
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If (Present(itrace)) Then
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itrace_ = itrace
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Else
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itrace_ = 0
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End If
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If (Present(irst)) Then
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nl = irst
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If (debug) Write(0,*) 'present: irst: ',irst,nl
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Else
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nl = 10
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If (debug) Write(0,*) 'not present: irst: ',irst,nl
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Endif
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if (nl <=0 ) then
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write(0,*) 'psb_dgmres: invalid irst ',nl
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info=5001
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int_err(1)=nl
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err=info
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call psb_errpush(info,name,i_err=int_err)
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goto 9999
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endif
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call psb_chkvect(mglob,1,size(x,1),1,1,desc_a,info)
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if(info /= 0) then
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info=4010
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call psb_errpush(info,name,a_err='psb_chkvect on X')
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goto 9999
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end if
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call psb_chkvect(mglob,1,size(b,1),1,1,desc_a,info)
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if(info /= 0) then
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info=4010
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call psb_errpush(info,name,a_err='psb_chkvect on B')
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goto 9999
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end if
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naux=4*n_col
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Allocate(aux(naux),h(nl+1,nl+1),&
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&c(nl+1),s(nl+1),rs(nl+1), rst(nl+1),stat=info)
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if (info == 0) Call psb_geall(v,desc_a,info,n=nl+1)
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if (info == 0) Call psb_geall(w,desc_a,info)
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if (info == 0) Call psb_geall(w1,desc_a,info)
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if (info == 0) Call psb_geall(xt,desc_a,info)
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if (info == 0) Call psb_geasb(v,desc_a,info)
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if (info == 0) Call psb_geasb(w,desc_a,info)
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if (info == 0) Call psb_geasb(w1,desc_a,info)
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if (info == 0) Call psb_geasb(xt,desc_a,info)
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if (info.ne.0) Then
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info=4011
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call psb_errpush(info,name)
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goto 9999
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End If
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if (debug) write(0,*) 'Size of V,W,W1 ',size(v),size(v,1),&
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&size(w),size(w,1),size(w1),size(w1,1), size(v(:,1))
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! Ensure global coherence for convergence checks.
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call psb_set_coher(ictxt,isvch)
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if (istop_ == 1) then
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ani = psb_spnrmi(a,desc_a,info)
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bni = psb_geamax(b,desc_a,info)
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else if (istop_ == 2) then
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bn2 = psb_genrm2(b,desc_a,info)
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endif
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if (info.ne.0) Then
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info=4011
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call psb_errpush(info,name)
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goto 9999
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End If
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itx = 0
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restart: Do
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! compute r0 = b-ax0
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! check convergence
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! compute v1 = r0/||r0||_2
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If (debug) Write(0,*) 'restart: ',itx,it
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it = 0
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Call psb_geaxpby(zone,b,zzero,v(:,1),desc_a,info)
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if (info.ne.0) Then
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info=4011
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call psb_errpush(info,name)
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goto 9999
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End If
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Call psb_spmm(-zone,a,x,zone,v(:,1),desc_a,info,work=aux)
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if (info.ne.0) Then
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info=4011
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call psb_errpush(info,name)
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goto 9999
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End If
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rs(1) = psb_genrm2(v(:,1),desc_a,info)
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rs(2:) = zzero
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if (info.ne.0) Then
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info=4011
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call psb_errpush(info,name)
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goto 9999
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End If
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scal=done/rs(1) ! rs(1) MIGHT BE VERY SMALL - USE DSCAL TO DEAL WITH IT?
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If (debug) Write(0,*) 'on entry to amax: b: ',Size(b),rs(1),scal
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!
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! check convergence
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!
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if (istop_ == 1) then
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rni = psb_geamax(v(:,1),desc_a,info)
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xni = psb_geamax(x,desc_a,info)
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rerr = rni/(ani*xni+bni)
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else if (istop_ == 2) then
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rni = psb_genrm2(v(:,1),desc_a,info)
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rerr = rni/bn2
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endif
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if (info.ne.0) Then
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info=4011
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call psb_errpush(info,name)
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goto 9999
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End If
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If (rerr<=eps) Then
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Exit restart
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End If
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If (itrace_ > 0) then
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if ((mod(itx,itrace_)==0).and.(me == 0))&
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& write(*,'(a,i4,3(2x,es10.4))') 'gmres(l): ',itx,rerr
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end If
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v(:,1) = v(:,1) * scal
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If (itx.Ge.litmax) Exit restart
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!
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! inner iterations
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!
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inner: Do i=1,nl
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itx = itx + 1
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call psb_precaply(prec,v(:,i),w1,desc_a,info)
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Call psb_spmm(zone,a,w1,zzero,w,desc_a,info,work=aux)
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!
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do k = 1, i
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h(k,i) = psb_gedot(v(:,k),w,desc_a,info)
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call psb_geaxpby(-h(k,i),v(:,k),zone,w,desc_a,info)
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end do
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h(i+1,i) = psb_genrm2(w,desc_a,info)
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scal=done/h(i+1,i)
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call psb_geaxpby(scal,w,zzero,v(:,i+1),desc_a,info)
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do k=2,i
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call zrot(1,h(k-1,i),1,h(k,i),1,real(c(k-1)),s(k-1))
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enddo
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rti = h(i,i)
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rti1 = h(i+1,i)
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call zrotg(rti,rti1,tmp,s(i))
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c(i) = cmplx(tmp,zzero)
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call zrot(1,h(i,i),1,h(i+1,i),1,real(c(i)),s(i))
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h(i+1,i) = zzero
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call zrot(1,rs(i),1,rs(i+1),1,real(c(i)),s(i))
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if (istop_ == 1) then
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!
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! build x and then compute the residual and its infinity norm
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!
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rst = rs
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xt = zzero
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call ztrsm('l','u','n','n',i,1,zone,h,size(h,1),rst,size(rst,1))
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if (debug) write(0,*) 'Rebuild x-> RS:',rst(1:nl)
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do k=1, i
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call psb_geaxpby(rst(k),v(:,k),zone,xt,desc_a,info)
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end do
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call psb_precaply(prec,xt,desc_a,info)
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call psb_geaxpby(zone,x,zone,xt,desc_a,info)
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call psb_geaxpby(zone,b,zzero,w1,desc_a,info)
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call psb_spmm(-zone,a,xt,zone,w1,desc_a,info,work=aux)
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rni = psb_geamax(w1,desc_a,info)
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xni = psb_geamax(xt,desc_a,info)
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rerr = rni/(ani*xni+bni)
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!
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else if (istop_ == 2) then
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!
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! compute the residual 2-norm as byproduct of the solution
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! procedure of the least-squares problem
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!
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rni = abs(rs(i+1))
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rerr = rni/bn2
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endif
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if (rerr < eps ) then
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if (istop_ == 1) then
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x = xt
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else if (istop_ == 2) then
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!
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! build x
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!
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call ztrsm('l','u','n','n',i,1,zone,h,size(h,1),rs,size(rs,1))
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if (debug) write(0,*) 'Rebuild x-> RS:',rs(21:nl)
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w1 = zzero
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do k=1, i
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call psb_geaxpby(rs(k),v(:,k),zone,w1,desc_a,info)
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end do
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call psb_precaply(prec,w1,w,desc_a,info)
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call psb_geaxpby(zone,w,zone,x,desc_a,info)
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end if
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exit restart
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end if
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If (itrace_ > 0) then
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if ((mod(itx,itrace_)==0).and.(me == 0))&
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& write(*,'(a,i4,3(2x,es10.4))') 'gmres(l): ',itx,rerr
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end If
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end Do inner
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if (istop_ == 1) then
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x = xt
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else if (istop_ == 2) then
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!
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! build x
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!
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call ztrsm('l','u','n','n',nl,1,zone,h,size(h,1),rs,size(rs,1))
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if (debug) write(0,*) 'Rebuild x-> RS:',rs(21:nl)
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w1 = zzero
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do k=1, nl
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call psb_geaxpby(rs(k),v(:,k),zone,w1,desc_a,info)
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end do
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call psb_precaply(prec,w1,w,desc_a,info)
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call psb_geaxpby(zone,w,zone,x,desc_a,info)
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end if
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End Do restart
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If (itrace_ > 0) then
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if (me == 0) write(*,'(a,i4,3(2x,es10.4))') 'gmres(l): ',itx,rerr
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end If
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If (Present(err)) err=rerr
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If (Present(iter)) iter = itx
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If ((rerr>eps).and. (me == 0)) Then
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Write(0,*) 'gmresr(l) failed to converge to ',eps,&
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& ' in ',itx,' iterations '
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End If
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Deallocate(aux,h,c,s,rs,rst, stat=info)
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Call psb_gefree(v,desc_a,info)
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Call psb_gefree(w,desc_a,info)
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Call psb_gefree(w1,desc_a,info)
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Call psb_gefree(xt,desc_a,info)
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! restore external global coherence behaviour
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call psb_restore_coher(ictxt,isvch)
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if (info /= 0) then
|
||||
info=4011
|
||||
call psb_errpush(info,name)
|
||||
goto 9999
|
||||
end if
|
||||
|
||||
call psb_erractionrestore(err_act)
|
||||
return
|
||||
|
||||
9999 continue
|
||||
call psb_erractionrestore(err_act)
|
||||
if (err_act.eq.psb_act_abort_) then
|
||||
call psb_error()
|
||||
return
|
||||
end if
|
||||
return
|
||||
|
||||
|
||||
contains
|
||||
function safe_dn2(a,b)
|
||||
real(kind(1.d0)), intent(in) :: a, b
|
||||
real(kind(1.d0)) :: safe_dn2
|
||||
real(kind(1.d0)) :: t
|
||||
|
||||
t = max(abs(a),abs(b))
|
||||
if (t==0.d0) then
|
||||
safe_dn2 = 0.d0
|
||||
else
|
||||
safe_dn2 = t * sqrt(abs(a/t)**2 + abs(b/t)**2)
|
||||
endif
|
||||
return
|
||||
end function safe_dn2
|
||||
|
||||
|
||||
End Subroutine psb_zgmresr
|
||||
|
||||
|
||||
subroutine zrot( n, cx, incx, cy, incy, c, s )
|
||||
!
|
||||
! -- lapack auxiliary routine (version 3.0) --
|
||||
! univ. of tennessee, univ. of california berkeley, nag ltd.,
|
||||
! courant institute, argonne national lab, and rice university
|
||||
! october 31, 1992
|
||||
!
|
||||
! .. scalar arguments ..
|
||||
integer incx, incy, n
|
||||
real(kind(1.d0)) c
|
||||
complex(kind(1.d0)) s
|
||||
! ..
|
||||
! .. array arguments ..
|
||||
complex(kind(1.d0)) cx( * ), cy( * )
|
||||
! ..
|
||||
!
|
||||
! purpose
|
||||
! =======
|
||||
!
|
||||
! zrot applies a plane rotation, where the cos (c) is real and the
|
||||
! sin (s) is complex, and the vectors cx and cy are complex.
|
||||
!
|
||||
! arguments
|
||||
! =========
|
||||
!
|
||||
! n (input) integer
|
||||
! the number of elements in the vectors cx and cy.
|
||||
!
|
||||
! cx (input/output) complex*16 array, dimension (n)
|
||||
! on input, the vector x.
|
||||
! on output, cx is overwritten with c*x + s*y.
|
||||
!
|
||||
! incx (input) integer
|
||||
! the increment between successive values of cy. incx <> 0.
|
||||
!
|
||||
! cy (input/output) complex*16 array, dimension (n)
|
||||
! on input, the vector y.
|
||||
! on output, cy is overwritten with -conjg(s)*x + c*y.
|
||||
!
|
||||
! incy (input) integer
|
||||
! the increment between successive values of cy. incx <> 0.
|
||||
!
|
||||
! c (input) double precision
|
||||
! s (input) complex*16
|
||||
! c and s define a rotation
|
||||
! [ c s ]
|
||||
! [ -conjg(s) c ]
|
||||
! where c*c + s*conjg(s) = 1.0.
|
||||
!
|
||||
! =====================================================================
|
||||
!
|
||||
! .. local scalars ..
|
||||
integer i, ix, iy
|
||||
complex(kind(1.d0)) stemp
|
||||
! ..
|
||||
! .. intrinsic functions ..
|
||||
intrinsic dconjg
|
||||
! ..
|
||||
! .. executable statements ..
|
||||
!
|
||||
if( n.le.0 ) return
|
||||
if( incx.eq.1 .and. incy.eq.1 ) then
|
||||
!
|
||||
! code for both increments equal to 1
|
||||
!
|
||||
do i = 1, n
|
||||
stemp = c*cx(i) + s*cy(i)
|
||||
cy(i) = c*cy(i) - dconjg(s)*cx(i)
|
||||
cx(i) = stemp
|
||||
end do
|
||||
else
|
||||
!
|
||||
! code for unequal increments or equal increments not equal to 1
|
||||
!
|
||||
ix = 1
|
||||
iy = 1
|
||||
if( incx.lt.0 )ix = ( -n+1 )*incx + 1
|
||||
if( incy.lt.0 )iy = ( -n+1 )*incy + 1
|
||||
do i = 1, n
|
||||
stemp = c*cx(ix) + s*cy(iy)
|
||||
cy(iy) = c*cy(iy) - dconjg(s)*cx(ix)
|
||||
cx(ix) = stemp
|
||||
ix = ix + incx
|
||||
iy = iy + incy
|
||||
end do
|
||||
end if
|
||||
return
|
||||
return
|
||||
end subroutine zrot
|
||||
!
|
||||
!
|
||||
subroutine zrotg(ca,cb,c,s)
|
||||
complex(kind(1.d0)) ca,cb,s
|
||||
real(kind(1.d0)) c
|
||||
real(kind(1.d0)) norm,scale
|
||||
complex(kind(1.d0)) alpha
|
||||
!
|
||||
if (cdabs(ca) == 0.0d0) then
|
||||
!
|
||||
c = 0.0d0
|
||||
s = (1.0d0,0.0d0)
|
||||
ca = cb
|
||||
return
|
||||
end if
|
||||
!
|
||||
|
||||
scale = cdabs(ca) + cdabs(cb)
|
||||
norm = scale*dsqrt((cdabs(ca/dcmplx(scale,0.0d0)))**2 +&
|
||||
& (cdabs(cb/dcmplx(scale,0.0d0)))**2)
|
||||
alpha = ca /cdabs(ca)
|
||||
c = cdabs(ca) / norm
|
||||
s = alpha * dconjg(cb) / norm
|
||||
ca = alpha * norm
|
||||
!
|
||||
|
||||
return
|
||||
end subroutine zrotg
|
||||
Loading…
Reference in New Issue