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siyuan
[专家分：0] 发布于 2010-04-11 14:47:00
subroutine ssor(a,n,b,x,eps,om,ii)
parameter(imax=200)
real a(n,n),b(n),x(n)
integer i,j,ii
real r,rx
do i=1,n
r=1/a(i,i)
b(i)=b(i)*r
do j=1,n
a(i,j)=a(i,j)*r
end do
end do
do ii=1,imax
rx=0.0
do i=1,n
r=b(i)
do j=1,n
r=r-a(i,j)*x(j)
enddo
if (abs(r)>rx)rx=abs(r)
x(i)=x(i)+om*r
enddo
if(om*rx<=eps) return
enddo
pause 'too many iterations'
end subroutine ssor
program dir12
! drive program for routine ssor
parameter(n=99,eps=1.e-4,om=1.3)
dimension a(n,n),c(n,n),r(n),b(n),x(n)
do i=1,n
a(i,i)=-(1+v*cos((i+1/2)*u))**3-(1+v*cos((i-1/2)*u))**3
enddo
do i=1,n-1
a(i,i+1)=(1+v*cos((i+1/2)*u))**3
a(i+1,i)=(1+v*cos((i-1/2)*u))**3
enddo
do i=1,n
b(i)=3*v*u*(cos((i+1/2)*u)-cos((i-1/2)*u))
enddo
do i=1,n
do j=1,n
c(i,j)=a(i,j)
enddo
enddo
do l=1,n
r(l)=b(l)
x(l)=0.0
enddo
call ssor(c,n,r,x,eps,om,ii)
write(*,*) 'solution vector'
write(*,'(1x,5f12.6)') (x(l) l=1,n)
!test results with original matrix
write(*,*) 'right-hand side vector'
write(*,'(1x,5f12.6)') (b(l) l=1,n)
write(*,*) 'result of matrix applied to sol' 'n vector'
do l=1,n
b(l)=0.0
do j=1,n
b(l)=b(l)+a(l,j)*x(j)
enddo
enddo
write(*,'(1x,5f12.6)') (b(l) l=1,n)
write(*,*) 'iteration times=',ii
end
parameter(imax=200)
real a(n,n),b(n),x(n)
integer i,j,ii
real r,rx
do i=1,n
r=1/a(i,i)
b(i)=b(i)*r
do j=1,n
a(i,j)=a(i,j)*r
end do
end do
do ii=1,imax
rx=0.0
do i=1,n
r=b(i)
do j=1,n
r=r-a(i,j)*x(j)
enddo
if (abs(r)>rx)rx=abs(r)
x(i)=x(i)+om*r
enddo
if(om*rx<=eps) return
enddo
pause 'too many iterations'
end subroutine ssor
program dir12
! drive program for routine ssor
parameter(n=99,eps=1.e-4,om=1.3)
dimension a(n,n),c(n,n),r(n),b(n),x(n)
do i=1,n
a(i,i)=-(1+v*cos((i+1/2)*u))**3-(1+v*cos((i-1/2)*u))**3
enddo
do i=1,n-1
a(i,i+1)=(1+v*cos((i+1/2)*u))**3
a(i+1,i)=(1+v*cos((i-1/2)*u))**3
enddo
do i=1,n
b(i)=3*v*u*(cos((i+1/2)*u)-cos((i-1/2)*u))
enddo
do i=1,n
do j=1,n
c(i,j)=a(i,j)
enddo
enddo
do l=1,n
r(l)=b(l)
x(l)=0.0
enddo
call ssor(c,n,r,x,eps,om,ii)
write(*,*) 'solution vector'
write(*,'(1x,5f12.6)') (x(l) l=1,n)
!test results with original matrix
write(*,*) 'right-hand side vector'
write(*,'(1x,5f12.6)') (b(l) l=1,n)
write(*,*) 'result of matrix applied to sol' 'n vector'
do l=1,n
b(l)=0.0
do j=1,n
b(l)=b(l)+a(l,j)*x(j)
enddo
enddo
write(*,'(1x,5f12.6)') (b(l) l=1,n)
write(*,*) 'iteration times=',ii
end