init.for

2D有限差分法程序,未加边界条件,适合一般情况下的波动方程模拟

!     copyright:wangaifeng 
!     DATE     :2007-07-25
!     Company  :GUCAS
      subroutine init(u,nx,ny,ighost,gama)
	implicit real(a-h,o-z)
	real u(-ighost:nx+ighost,-ighost:ny+ighost,0:3)

	do i=-ighost,nx/2
	 do j=-ighost,ny/2
	 u(i,j,0)=0.5
       u(i,j,1)=0.5*3.0
	 u(i,j,2)=0.5*1.0
	 u(i,j,3)=1.0/(gama-1)+0.5*0.5*10
	enddo
	enddo

	do i=nx/2+1,nx+ighost
	 do j=-ighost,ny/2
	 u(i,j,0)=1.5
       u(i,j,1)=1.5*3.0
	 u(i,j,2)=-1.5*1.0
	 u(i,j,3)=1.0/(gama-1)+0.5*1.5*10
	enddo
	enddo

	do i=nx/2+1,nx+ighost
	 do j=ny/2+1,ny+ighost
	 u(i,j,0)=0.5
       u(i,j,1)=-0.5*3.0
	 u(i,j,2)=-0.5*1.0
	 u(i,j,3)=1.0/(gama-1)+0.5*0.5*10
	enddo
	enddo

	do i=-ighost,nx/2
	 do j=ny/2+1,ny+ighost
	 u(i,j,0)=1.5
       u(i,j,1)=-1.5*3.0
	 u(i,j,2)=1.5*1.0
	 u(i,j,3)=1.0/(gama-1)+0.5*1.5*10
	enddo
	enddo

	end