example.txt

这是我学习并行编程的第一个程序

program example1
include “mpif.h” !! MPI 系统头文件
integer status(MPI_STATUS_SIZE),my_rank,p,source,dest,tag,ierr,data
c
c-------进入MPI 系统
call MPI_Init(ierr)
call MPI_Comm_rank(MPI_COMM_WORLD,my_rank,ierr)
call MPI_Comm_size(MPI_COMM_WORLD,p,ierr)
c
c-------数据交换
data=0
tag = 5
source= my_rank-1
if(source.eq.-1) source=p-1
dest =my_rank+1
if(dest.eq.p) dest=0
if(my_rank.eq.0) then
call MPI_Send(data,1,MPI_INTEGER,dest,tag,MPI_COMM_WORLD,ierr)
call MPI_Recv(data,1,MPI_INTEGER,source,tag,MPI_COMM_WORLD,status,ierr)
else
call MPI_Recv(data,1,MPI_INTEGER,source,tag,MPI_COMM_WORLD,status,ierr)
data=data+1
call MPI_Send(data,1,MPI_INTEGER,dest,tag,MPI_COMM_WORLD,ierr)
endif
c
c-------广播数据
call MPI_Bcast(data,1,MPI_INTEGER,0,MPI_COMM_WORLD,ierr)
c
c------打印输出
if(my_rank.eq.0) then
if(data.eq.p-1) then
print *,”Successful, data=”,data
else
print *,”Failure, data=”,data
endif
endif
c
call MPI_Finalize(ierr)
end