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psblas3/test/pargen/ppde90.f90

739 lines
22 KiB
Fortran

19 years ago
!
! This sample program shows how to build and solve a sparse linear
!
! The program solves a linear system based on the partial differential
! equation
!
!
!
! the equation generated is:
! b1 d d (u) b2 d d (u) a1 d (u)) a2 d (u)))
! - ------ - ------ + ----- + ------ + a3 u = 0
! dx dx dy dy dx dy
!
!
! with Dirichlet boundary conditions on the unit cube
!
! 0<=x,y,z<=1
!
! The equation is discretized with finite differences and uniform stepsize;
! the resulting discrete equation is
!
! ( u(x,y,z)(2b1+2b2+a1+a2)+u(x-1,y)(-b1-a1)+u(x,y-1)(-b2-a2)+
! -u(x+1,y)b1-u(x,y+1)b2)*(1/h**2)
!
! Example taken from: C.T.Kelley
! Iterative Methods for Linear and Nonlinear Equations
! SIAM 1995
!
!
! In this sample program the index space of the discretized
! computational domain is first numbered sequentially in a standard way,
! then the corresponding vector is distributed according to an HPF BLOCK
! distribution directive.
!
! Boundary conditions are set in a very simple way, by adding
! equations of the form
!
! u(x,y) = rhs(x,y)
!
program pde90
use psb_sparse_mod
use psb_error_mod
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implicit none
interface
!.....user passed subroutine.....
subroutine part_block(glob_index,n,np,pv,nv)
integer, intent(in) :: glob_index, n, np
integer, intent(out) :: nv
integer, intent(out) :: pv(*)
end subroutine part_block
end interface
! input parameters
character :: cmethd*10, prec*10, afmt*5
integer :: idim, iret
! miscellaneous
character, parameter :: order='r'
integer :: iargc,convert_descr,dim, check_descr
real(kind(1.d0)), parameter :: dzero = 0.d0, one = 1.d0
real(kind(1.d0)) :: mpi_wtime, t1, t2, tprec, tsolve, t3, t4
external mpi_wtime
! sparse matrix and preconditioner
type(psb_dspmat_type) :: a, l, u, h
type(psb_dprec_type) :: pre
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! descriptor
type(psb_desc_type) :: desc_a, desc_a_out
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! dense matrices
real(kind(1.d0)), pointer :: b(:), x(:), d(:),ld(:)
integer, pointer :: work(:)
! blacs parameters
integer :: nprow, npcol, icontxt, iam, np, myprow, mypcol
! solver parameters
integer :: iter, itmax,ierr,itrace, methd,iprec, istopc,&
& iparm(20), ml
real(kind(1.d0)) :: err, eps, rparm(20)
! other variables
integer :: i,info
integer :: internal, m,ii
character(len=10) :: ptype
character(len=20) :: name,ch_err
info=0
name='pde90'
call psb_set_errverbosity(2)
call psb_set_erraction(0)
! initialize blacs
call blacs_pinfo(iam, np)
call blacs_get(izero, izero, icontxt)
! rectangular grid, p x 1
call blacs_gridinit(icontxt, order, np, ione)
call blacs_gridinfo(icontxt, nprow, npcol, myprow, mypcol)
!
! get parameters
!
call get_parms(icontxt,cmethd,prec,afmt,idim,istopc,itmax,itrace,ml)
!
! allocate and fill in the coefficient matrix, rhs and initial guess
!
call blacs_barrier(icontxt,'ALL')
t1 = mpi_wtime()
call create_matrix(idim,a,b,x,desc_a,part_block,icontxt,afmt,info)
t2 = mpi_wtime() - t1
if(info.ne.0) then
info=4010
ch_err='create_matrix'
call psb_errpush(info,name,a_err=ch_err)
goto 9999
end if
dim=size(a%aspk)
!!$ allocate(h%aspk(dim),h%ia1(dim),h%ia2(dim),h%pl(size(a%pl)),&
!!$ & h%pl(size(a%pl)),d(size(a%pl)),&
!!$ & desc_a_out%matrix_data(size(desc_a%matrix_data)),&
!!$ & desc_a_out%halo_index(size(desc_a%halo_index)),&
!!$ & desc_a_out%ovrlap_index(size(desc_a%ovrlap_index)),&
!!$ & desc_a_out%ovrlap_elem(size(desc_a%ovrlap_elem)),&
!!$ & desc_a_out%loc_to_glob(size(desc_a%loc_to_glob)),&
!!$ & desc_a_out%glob_to_loc(size(desc_a%glob_to_loc)), work(1024))
!!$ check_descr=15
! work(5)=9
!!$ write(0,*)'calling verify'
!!$ call f90_psverify(d,a,desc_a,check_descr,convert_descr,h,&
!!$ & desc_a_out,work)
!!$ write(0,*)'verify done',convert_descr
! deallocate(work)
call dgamx2d(icontxt,'a',' ',ione, ione,t2,ione,t1,t1,-1,-1,-1)
if (iam.eq.0) write(6,*) 'matrix creation time : ',t2
!
! prepare the preconditioner.
!
write(0,*)'precondizionatore=',prec
select case (prec)
case ('ILU')
iprec = 2
ptype='bja'
call psb_precset(pre,ptype)
case ('DIAGSC')
iprec = 1
ptype='diagsc'
call psb_precset(pre,ptype)
case ('NONE')
iprec = 0
ptype='noprec'
call psb_precset(pre,ptype)
case default
info=5003
ch_err(1:3)=prec(1:3)
call psb_errpush(info,name,a_err=ch_err)
goto 9999
end select
write(0,*)'preconditioner set'
call blacs_barrier(icontxt,'ALL')
t1 = mpi_wtime()
call psb_precbld(a,pre,desc_a,info)!,'f')
if(info.ne.0) then
info=4010
ch_err='psb_precbld'
call psb_errpush(info,name,a_err=ch_err)
goto 9999
end if
tprec = mpi_wtime()-t1
call dgamx2d(icontxt,'a',' ',ione, ione,tprec,ione,t1,t1,-1,-1,-1)
if (iam.eq.0) write(6,*) 'preconditioner time : ',tprec
!
! iterative method parameters
!
write(*,*) 'calling iterative method', a%ia2(7999:8001)
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call blacs_barrier(icontxt,'ALL')
t1 = mpi_wtime()
eps = 1.d-9
if (cmethd.eq.'BICGSTAB') then
call psb_bicgstab(a,pre,b,x,eps,desc_a,info,&
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& itmax,iter,err,itrace)
else if (cmethd.eq.'CGS') then
call psb_cgs(a,pre,b,x,eps,desc_a,info,&
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& itmax,iter,err,itrace)
else if (cmethd.eq.'BICGSTABL') then
call psb_bicgstabl(a,pre,b,x,eps,desc_a,info,&
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& itmax,iter,err,itrace,ml)
else
write(0,*) 'unknown method ',cmethd
end if
if(info.ne.0) then
info=4010
ch_err='solver routine'
call psb_errpush(info,name,a_err=ch_err)
goto 9999
end if
call blacs_barrier(icontxt,'ALL')
t2 = mpi_wtime() - t1
call dgamx2d(icontxt,'a',' ',ione, ione,t2,ione,t1,t1,-1,-1,-1)
if (iam.eq.0) then
write(6,*) 'time to solve matrix : ',t2
write(6,*) 'time per iteration : ',t2/iter
write(6,*) 'number of iterations : ',iter
write(6,*) 'error on exit : ',err
write(6,*) 'info on exit : ',ierr
end if
!
! cleanup storage and exit
!
call psb_free(b,desc_a,info)
call psb_free(x,desc_a,info)
call psb_spfree(a,desc_a,info)
call psb_dscfree(desc_a,info)
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if(info.ne.0) then
info=4010
ch_err='free routine'
call psb_errpush(info,name,a_err=ch_err)
goto 9999
end if
9999 continue
if(info /= 0) then
call psb_error(icontxt)
call blacs_gridexit(icontxt)
call blacs_exit(0)
else
call blacs_gridexit(icontxt)
call blacs_exit(0)
end if
stop
contains
!
! get iteration parameters from the command line
!
subroutine get_parms(icontxt,cmethd,prec,afmt,idim,istopc,itmax,itrace,ml)
integer :: icontxt
character :: cmethd*10, prec*10, afmt*5
integer :: idim, iret, istopc,itmax,itrace,ml
character*40 :: charbuf
integer :: iargc, nprow, npcol, myprow, mypcol
external iargc
integer :: intbuf(10), ip
call blacs_gridinfo(icontxt, nprow, npcol, myprow, mypcol)
if (myprow==0) then
read(*,*) ip
if (ip.ge.3) then
read(*,*) cmethd
read(*,*) prec
read(*,*) afmt
! convert strings in array
do i = 1, len(cmethd)
intbuf(i) = iachar(cmethd(i:i))
end do
! broadcast parameters to all processors
call igebs2d(icontxt,'ALL',' ',10,1,intbuf,10)
do i = 1, len(prec)
intbuf(i) = iachar(prec(i:i))
end do
! broadcast parameters to all processors
call igebs2d(icontxt,'ALL',' ',10,1,intbuf,10)
do i = 1, len(afmt)
intbuf(i) = iachar(afmt(i:i))
end do
! broadcast parameters to all processors
call igebs2d(icontxt,'ALL',' ',10,1,intbuf,10)
read(*,*) idim
if (ip.ge.4) then
read(*,*) istopc
else
istopc=1
endif
if (ip.ge.5) then
read(*,*) itmax
else
itmax=500
endif
if (ip.ge.6) then
read(*,*) itrace
else
itrace=-1
endif
if (ip.ge.7) then
read(*,*) ml
else
ml=1
endif
! broadcast parameters to all processors
intbuf(1) = idim
intbuf(2) = istopc
intbuf(3) = itmax
intbuf(4) = itrace
intbuf(5) = ml
call igebs2d(icontxt,'ALL',' ',5,1,intbuf,5)
write(6,*)'solving matrix: ell1'
write(6,*)'on grid',idim,'x',idim,'x',idim
write(6,*)' with block data distribution, np=',np,&
& ' preconditioner=',prec,&
& ' iterative methd=',cmethd
else
! wrong number of parameter, print an error message and exit
call pr_usage(0)
call blacs_abort(icontxt,-1)
stop 1
endif
else
! receive parameters
call igebr2d(icontxt,'ALL',' ',10,1,intbuf,10,0,0)
do i = 1, 10
cmethd(i:i) = achar(intbuf(i))
end do
call igebr2d(icontxt,'ALL',' ',10,1,intbuf,10,0,0)
do i = 1, 10
prec(i:i) = achar(intbuf(i))
end do
call igebr2d(icontxt,'ALL',' ',10,1,intbuf,10,0,0)
do i = 1, 5
afmt(i:i) = achar(intbuf(i))
end do
call igebr2d(icontxt,'ALL',' ',5,1,intbuf,5,0,0)
idim = intbuf(1)
istopc = intbuf(2)
itmax = intbuf(3)
itrace = intbuf(4)
ml = intbuf(5)
end if
return
end subroutine get_parms
!
! print an error message
!
subroutine pr_usage(iout)
integer :: iout
write(iout,*)'incorrect parameter(s) found'
write(iout,*)' usage: pde90 methd prec dim &
&[istop itmax itrace]'
write(iout,*)' where:'
write(iout,*)' methd: cgstab tfqmr cgs'
write(iout,*)' prec : ilu diagsc none'
write(iout,*)' dim number of points along each axis'
write(iout,*)' the size of the resulting linear '
write(iout,*)' system is dim**3'
write(iout,*)' istop stopping criterion 1, 2 or 3 [1] '
write(iout,*)' itmax maximum number of iterations [500] '
write(iout,*)' itrace 0 (no tracing, default) or '
write(iout,*)' >= 0 do tracing every itrace'
write(iout,*)' iterations '
end subroutine pr_usage
!
! subroutine to allocate and fill in the coefficient matrix and
! the rhs.
!
subroutine create_matrix(idim,a,b,t,desc_a,parts,icontxt,afmt,info)
!
! discretize the partial diferential equation
!
! b1 dd(u) b2 dd(u) b3 dd(u) a1 d(u) a2 d(u) a3 d(u)
! - ------ - ------ - ------ - ----- - ------ - ------ + a4 u
! dxdx dydy dzdz dx dy dz
!
! = 0
!
! boundary condition: dirichlet
! 0< x,y,z<1
!
! u(x,y,z)(2b1+2b2+2b3+a1+a2+a3)+u(x-1,y,z)(-b1-a1)+u(x,y-1,z)(-b2-a2)+
! + u(x,y,z-1)(-b3-a3)-u(x+1,y,z)b1-u(x,y+1,z)b2-u(x,y,z+1)b3
use psb_spmat_type
use psb_descriptor_type
use psb_tools_mod
use psb_methd_mod
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implicit none
integer :: idim
integer, parameter :: nbmax=10
real(kind(1.d0)),pointer :: b(:),t(:)
type(psb_desc_type) :: desc_a
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integer :: icontxt, info
character :: afmt*5
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interface
! .....user passed subroutine.....
subroutine parts(global_indx,n,np,pv,nv)
implicit none
integer, intent(in) :: global_indx, n, np
integer, intent(out) :: nv
integer, intent(out) :: pv(*)
end subroutine parts
end interface ! local variables
type(psb_dspmat_type) :: a
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real(kind(1.d0)) :: zt(nbmax),glob_x,glob_y,glob_z
integer :: m,n,nnz,glob_row,j
type(psb_dspmat_type) :: row_mat
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integer :: x,y,z,counter,ia,i,indx_owner
integer :: nprow,npcol,myprow,mypcol
integer :: element
integer :: nv, inv
integer, allocatable :: prv(:)
integer, pointer :: ierrv(:)
real(kind(1.d0)), pointer :: dwork(:)
integer,pointer :: iwork(:)
! deltah dimension of each grid cell
! deltat discretization time
real(kind(1.d0)) :: deltah
real(kind(1.d0)),parameter :: rhs=0.d0,one=1.d0,zero=0.d0
real(kind(1.d0)) :: mpi_wtime, t1, t2, t3, tins
real(kind(1.d0)) :: a1, a2, a3, a4, b1, b2, b3
external mpi_wtime,a1, a2, a3, a4, b1, b2, b3
integer :: nb, ir1, ir2, ipr, err_act
logical :: own
! common area
character(len=20) :: name, ch_err
info = 0
name = 'create_matrix'
call psb_erractionsave(err_act)
call blacs_gridinfo(icontxt, nprow, npcol, myprow, mypcol)
deltah = 1.d0/(idim-1)
! initialize array descriptor and sparse matrix storage. provide an
! estimate of the number of non zeroes
m = idim*idim*idim
n = m
nnz = ((n*9)/(nprow*npcol))
write(*,*) 'size: n ',n
call psb_dscall(n,n,parts,icontxt,desc_a,info)
write(*,*) 'allocating a : nnz',nnz, info
call psb_spalloc(a,desc_a,info,nnz=nnz)
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! define rhs from boundary conditions; also build initial guess
write(*,*) 'allocating b', info
call psb_alloc(n,b,desc_a,info)
write(*,*) 'allocating t', info
call psb_alloc(n,t,desc_a,info)
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if(info.ne.0) then
info=4010
ch_err='allocation rout.'
call psb_errpush(info,name,a_err=ch_err)
goto 9999
end if
! we build an auxiliary matrix consisting of one row at a
! time; just a small matrix. might be extended to generate
! a bunch of rows per call.
!
row_mat%descra(1:1) = 'G'
row_mat%fida = 'CSR'
write(*,*) 'allocating row_mat',20*nbmax
allocate(row_mat%aspk(20*nbmax),row_mat%ia1(20*nbmax),&
&row_mat%ia2(20*nbmax),prv(nprow),stat=info)
if (info.ne.0 ) then
info=4000
call psb_errpush(info,name)
goto 9999
endif
tins = 0.d0
call blacs_barrier(icontxt,'ALL')
t1 = mpi_wtime()
! loop over rows belonging to current process in a block
! distribution.
row_mat%ia2(1)=1
do glob_row = 1, n
call parts(glob_row,n,nprow,prv,nv)
do inv = 1, nv
indx_owner = prv(inv)
if (indx_owner == myprow) then
! local matrix pointer
element=0
! compute gridpoint coordinates
if (mod(glob_row,(idim*idim)).eq.0) then
x = glob_row/(idim*idim)
else
x = glob_row/(idim*idim)+1
endif
if (mod((glob_row-(x-1)*idim*idim),idim).eq.0) then
y = (glob_row-(x-1)*idim*idim)/idim
else
y = (glob_row-(x-1)*idim*idim)/idim+1
endif
z = glob_row-(x-1)*idim*idim-(y-1)*idim
! glob_x, glob_y, glob_x coordinates
glob_x=x*deltah
glob_y=y*deltah
glob_z=z*deltah
! check on boundary points
if (x.eq.1) then
element=element+1
row_mat%aspk(element)=one
row_mat%ia2(element)=(x-1)*idim*idim+(y-1)*idim+(z)
row_mat%ia1(element)=glob_row
else if (y.eq.1) then
element=element+1
row_mat%aspk(element)=one
row_mat%ia2(element)=(x-1)*idim*idim+(y-1)*idim+(z)
row_mat%ia1(element)=glob_row
else if (z.eq.1) then
element=element+1
row_mat%aspk(element)=one
row_mat%ia2(element)=(x-1)*idim*idim+(y-1)*idim+(z)
row_mat%ia1(element)=glob_row
else if (x.eq.idim) then
element=element+1
row_mat%aspk(element)=one
row_mat%ia2(element)=(x-1)*idim*idim+(y-1)*idim+(z)
row_mat%ia1(element)=glob_row
else if (y.eq.idim) then
element=element+1
row_mat%aspk(element)=one
row_mat%ia2(element)=(x-1)*idim*idim+(y-1)*idim+(z)
row_mat%ia1(element)=glob_row
else if (z.eq.idim) then
element=element+1
row_mat%aspk(element)=one
row_mat%ia2(element)=(x-1)*idim*idim+(y-1)*idim+(z)
row_mat%ia1(element)=glob_row
else
! internal point: build discretization
!
! term depending on (x-1,y,z)
!
element=element+1
row_mat%aspk(element)=-b1(glob_x,glob_y,glob_z)&
& -a1(glob_x,glob_y,glob_z)
row_mat%aspk(element) = row_mat%aspk(element)/(deltah*&
& deltah)
row_mat%ia2(element)=(x-2)*idim*idim+(y-1)*idim+(z)
row_mat%ia1(element)=glob_row
! term depending on (x,y-1,z)
element=element+1
row_mat%aspk(element)=-b2(glob_x,glob_y,glob_z)&
& -a2(glob_x,glob_y,glob_z)
row_mat%aspk(element) = row_mat%aspk(element)/(deltah*&
& deltah)
row_mat%ia2(element)=(x-1)*idim*idim+(y-2)*idim+(z)
row_mat%ia1(element)=glob_row
! term depending on (x,y,z-1)
element=element+1
row_mat%aspk(element)=-b3(glob_x,glob_y,glob_z)&
& -a3(glob_x,glob_y,glob_z)
row_mat%aspk(element) = row_mat%aspk(element)/(deltah*&
& deltah)
row_mat%ia2(element)=(x-1)*idim*idim+(y-1)*idim+(z-1)
row_mat%ia1(element)=glob_row
! term depending on (x,y,z)
element=element+1
row_mat%aspk(element)=2*b1(glob_x,glob_y,glob_z)&
& +2*b2(glob_x,glob_y,glob_z)&
& +2*b3(glob_x,glob_y,glob_z)&
& +a1(glob_x,glob_y,glob_z)&
& +a2(glob_x,glob_y,glob_z)&
& +a3(glob_x,glob_y,glob_z)
row_mat%aspk(element) = row_mat%aspk(element)/(deltah*&
& deltah)
row_mat%ia2(element)=(x-1)*idim*idim+(y-1)*idim+(z)
row_mat%ia1(element)=glob_row
! term depending on (x,y,z+1)
element=element+1
row_mat%aspk(element)=-b1(glob_x,glob_y,glob_z)
row_mat%aspk(element) = row_mat%aspk(element)/(deltah*&
& deltah)
row_mat%ia2(element)=(x-1)*idim*idim+(y-1)*idim+(z+1)
row_mat%ia1(element)=glob_row
! term depending on (x,y+1,z)
element=element+1
row_mat%aspk(element)=-b2(glob_x,glob_y,glob_z)
row_mat%aspk(element) = row_mat%aspk(element)/(deltah*&
& deltah)
row_mat%ia2(element)=(x-1)*idim*idim+(y)*idim+(z)
row_mat%ia1(element)=glob_row
! term depending on (x+1,y,z)
element=element+1
row_mat%aspk(element)=-b3(glob_x,glob_y,glob_z)
row_mat%aspk(element) = row_mat%aspk(element)/(deltah*&
& deltah)
row_mat%ia2(element)=(x)*idim*idim+(y-1)*idim+(z)
row_mat%ia1(element)=glob_row
endif
row_mat%m=1
row_mat%k=n
! row_mat%ia2(2)=element
! ia== global row index
ia=glob_row
!!$ ia=(x-1)*idim*idim+(y-1)*idim+(z)
!!$ write(0,*) 'inserting row ',ia,' on proc',myprow
t3 = mpi_wtime()
call psb_spins(element,row_mat%ia1,row_mat%ia2,row_mat%aspk,a,desc_a,info)
if(info.ne.0) exit
tins = tins + (mpi_wtime()-t3)
! build rhs
if (x==1) then
glob_y=(y-idim/2)*deltah
glob_z=(z-idim/2)*deltah
zt(1) = exp(-glob_y**2-glob_z**2)
else if ((y==1).or.(y==idim).or.(z==1).or.(z==idim)) then
glob_x=3*(x-1)*deltah
glob_y=(y-idim/2)*deltah
glob_z=(z-idim/2)*deltah
zt(1) = exp(-glob_y**2-glob_z**2)*exp(-glob_x)
else
zt(1) = 0.d0
endif
call psb_ins(1,b,ia,zt(1:1),desc_a,info)
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if(info.ne.0) exit
zt(1)=0.d0
call psb_ins(1,t,ia,zt(1:1),desc_a,info)
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if(info.ne.0) exit
end if
end do
end do
call blacs_barrier(icontxt,'ALL')
t2 = mpi_wtime()
if(info.ne.0) then
info=4010
ch_err='insert rout.'
call psb_errpush(info,name,a_err=ch_err)
goto 9999
end if
write(*,*) ' pspins time',tins
write(*,*) ' insert time',(t2-t1)
deallocate(row_mat%aspk,row_mat%ia1,row_mat%ia2)
write(*,*) 'calling spasb'
call blacs_barrier(icontxt,'ALL')
t1 = mpi_wtime()
call psb_dscasb(desc_a,info)
call psb_spasb(a,desc_a,info,dup=1,afmt=afmt)
call blacs_barrier(icontxt,'ALL')
t2 = mpi_wtime()
if(info.ne.0) then
info=4010
ch_err='asb rout.'
call psb_errpush(info,name,a_err=ch_err)
goto 9999
end if
write(0,*) ' assembly time',(t2-t1),' ',a%fida(1:4)
call psb_asb(b,desc_a,info)
call psb_asb(t,desc_a,info)
19 years ago
if(info.ne.0) then
info=4010
ch_err='asb rout.'
call psb_errpush(info,name,a_err=ch_err)
goto 9999
end if
if (myprow.eq.0) then
write(0,*) ' end create_matrix'
endif
call psb_erractionrestore(err_act)
return
9999 continue
call psb_erractionrestore(err_act)
if (err_act.eq.act_abort) then
call psb_error(icontxt)
return
end if
return
end subroutine create_matrix
end program pde90
!
! functions parametrizing the differential equation
!
function a1(x,y,z)
real(kind(1.d0)) :: a1
real(kind(1.d0)) :: x,y,z
a1=1.d0
end function a1
function a2(x,y,z)
real(kind(1.d0)) :: a2
real(kind(1.d0)) :: x,y,z
a2=2.d1*y
end function a2
function a3(x,y,z)
real(kind(1.d0)) :: a3
real(kind(1.d0)) :: x,y,z
a3=1.d0
end function a3
function a4(x,y,z)
real(kind(1.d0)) :: a4
real(kind(1.d0)) :: x,y,z
a4=1.d0
end function a4
function b1(x,y,z)
real(kind(1.d0)) :: b1
real(kind(1.d0)) :: x,y,z
b1=1.d0
end function b1
function b2(x,y,z)
real(kind(1.d0)) :: b2
real(kind(1.d0)) :: x,y,z
b2=1.d0
end function b2
function b3(x,y,z)
real(kind(1.d0)) :: b3
real(kind(1.d0)) :: x,y,z
b3=1.d0
end function b3