Making my NumPy array shared across processes

Question

I have read quite a few of the questions on SO about sharing arrays and it seems simple enough for simple arrays but I am stuck trying to get it working for the array I have

Answer 1

from multiprocessing import Process, Array
import numpy as np
import time
import ctypes

def fun(a):
    a[0] = -a[0]
    while 1:
        time.sleep(2)
        #print bytearray(a.get_obj())
        c=np.frombuffer(a.get_obj(),dtype=np.float32)
        c.shape=3,3
        print 'haha',c


def main():
    a = np.random.rand(3,3).astype(np.float32)
    a.shape=1*a.size
    #a=np.array([[1,3,4],[4,5,6]])
    #b=bytearray(a)
    h=Array(ctypes.c_float,a)
    print "Originally,",h

    # Create, start, and finish the child process
    p = Process(target=fun, args=(h,))
    p.start()
    #p.join()
    a.shape=3,3
    # Print out the changed values
    print 'first',a
    time.sleep(3)
    #h[0]=h[0]+1
    print 'main',np.frombuffer(h.get_obj(), dtype=np.float32)



if __name__=="__main__":
    main()