我正在尝试在 python 中使用 MPI 为中点集成做一些并行计算。我对 MPI 不是很熟悉，我已经查看了一些示例来生成我迄今为止所拥有的内容。我遇到了几个错误，其中 MPI.COMM 无法识别几个输入参数。同样，我对 MPI 并不熟悉。
下面我附上了我的代码：
from mpi4py import MPI
import numpy as np
from numpy import *
import time
#initialize variables
n = 10e5 #number of increments within each process
a = 0.0; #lower bound
b = 5.0; #upper bound
dest = 0; #define the process that computes the final result
#Functions
def integral(my_a, num, h):
s = 0;
h2 = h/2;
for i in range(0,num):
temp = my_a + i*h;
s = s + fct(temp+h2)*h;
return (s)
def fct(x):
return x**2;
#Start the MPI process
comm = MPI.COMM_WORLD
p = comm.Get_size(); #gather number of processes
print "Number of processes (p): ", p;
myid = comm.Get_rank() #gather rank of the comm (number of cores)
print "Rank of (p): ", myid;
h = (b-a)/n; #length of increment
num = int(n/p); #number of intervals calculated by each process
print "Number of intervals calculated by a process: ", num;
my_range = (b-a)/p; #range per process
my_a = a + myid*my_range; #next lower limit
ti = time.clock();
my_result = integral(my_a,num,h) #get the result
print "Process " + str(myid) + " has the partial result of " + str(my_result) + ".";
if myid == 0:
result = my_result;
for i in range(1,p):
source = 1;
comm.recv(my_result, dest=1, tag=123);
result = result + my_result;
print "The result = " + str(result) + ".";
else :
comm.send(my_result, source=0, tag=123);
MPI_Finalize();
tf = time.clock();
print "Time(s): ", tf-ti;
这是我尝试运行此代码时遇到的错误：
--------------------------------------------------------------------------
*******************************-VirtualBox ~/Documents/ME701/HW/HW5 $ mpirun -np 2 python HW5_prb3.py
Number of processes (p): 2
Rank of (p): 1
Number of intervals calculated by a process: 500000
Number of processes (p): 2
Rank of (p): 0
Number of intervals calculated by a process: 500000
Process 1 has the partial result of 36.4583333333.
Traceback (most recent call last):
File "HW5_prb3.py", line 50, in <module>
comm.send(my_result, source=0, tag=123);
File "Comm.pyx", line 1127, in mpi4py.MPI.Comm.send (src/mpi4py.MPI.c:90067)
**TypeError: send() got an unexpected keyword argument 'source'**
Process 0 has the partial result of 5.20833333333.
Traceback (most recent call last):
File "HW5_prb3.py", line 45, in <module>
comm.recv(my_result, dest=1, tag=123);
File "Comm.pyx", line 1142, in mpi4py.MPI.Comm.recv (src/mpi4py.MPI.c:90513)
**TypeError: recv() got an unexpected keyword argument 'dest'**
-------------------------------------------------------
Primary job terminated normally, but 1 process returned
a non-zero exit code.. Per user-direction, the job has been aborted.
-------------------------------------------------------
--------------------------------------------------------------------------
mpirun detected that one or more processes exited with non-zero status, thus causing
the job to be terminated. The first process to do so was:
Process name: [[45152,1],1]
Exit code: 1
--------------------------------------------------------------------------
*******************************-VirtualBox ~/Documents/ME701/HW/HW5 $
中点积分的答案应该是 41.66667。我的老师只是想让我们对并行计算进行一次简单的时间研究，这样我们就可以看到它的力量。
感谢您的时间。