gistfile1.txt

import random
import ctypes
import operator
from time import time
from numpy import frombuffer, complex64, empty, mean, ctypeslib

SAMPLE_SIZE = 1*10**6
RUNS = 1

isamples = ctypes.c_byte * SAMPLE_SIZE
fsamples = ctypes.c_float * SAMPLE_SIZE

data = [isamples(*[random.randrange(0, 255) for i in xrange(SAMPLE_SIZE)]) for j in xrange(RUNS)]


def original(b):
    iq = empty(len(b)//2, complex64)
    iq.real, iq.imag = b[::2], b[1::2]
    iq /= (255/2)
    iq -= (1 + 1j)
    return iq


def masse1234(b):
    b_np = ctypeslib.as_array(b)
    iq = empty(len(b)//2, complex64)
    iq.real, iq.imag = b_np[::2], b_np[1::2]
    iq /= (255/2)
    iq -= (1 + 1j)
    return iq


def sliceassign(b):
    f = fsamples()
    f[:] = b
    c = frombuffer(f, complex64)
    c /= (255/2)
    c -= (1 + 1j)
    return c


def starassign(b):
    f = fsamples(*b)
    c = frombuffer(f, complex64)
    c /= (255/2)
    c -= (1 + 1j)
    return c


def run():
    results = []
    for test in original, masse1234, sliceassign, starassign:
        times = []
        for b in data:
            start = time()
            results.append(test(b))
            times.append(time() - start)
        print test.__name__, mean(times)
    return results


print "starting test"
results = run()