def test_update3(self):
f = tempfile.TemporaryFile()
m = 16384
flen = (m * 3) + mmap.PAGESIZE - (m * 3) % mmap.PAGESIZE
self.assertGreater(flen, m * 3)
f.write(''.join(['\x00' for i in range(flen)]))
fmap = mmap.mmap(f.fileno(), m * 3)
self.assertEqual(len(fmap), m * 3)
mslice1 = MmapSlice(fmap, m, 0)
mslice2 = MmapSlice(fmap, m, m)
mslice3 = MmapSlice(fmap, m, m * 2)
hll1 = HyperLogLog(self.error_rate, mslice1)
hll2 = HyperLogLog(self.error_rate, mslice2)
hll3 = HyperLogLog(self.error_rate, mslice3)
for v in self.test_data1:
hll1.add(v)
for v in self.test_data2:
hll2.add(v)
for v in self.test_data3:
hll3.add(v)
hll1.update([hll2, hll3])
self.assertAlmostEqual(self.test_set_size * 3,
len(hll1),
delta=self.test_set_size * 3 * self.error_rate)
def test_update(self):
a = HyperLogLog(0.05)
b = HyperLogLog(0.05)
c = HyperLogLog(0.05)
for i in xrange(2):
a.add(str(i))
c.add(str(i))
for i in xrange(2, 4):
b.add(str(i))
c.add(str(i))
a.update(b)
self.assertNotEqual(a, b)
self.assertNotEqual(b, c)
self.assertEqual(a, c)
def test_pickle(self):
a = HyperLogLog(0.05)
for x in range(100):
a.add(str(x))
b = pickle.loads(pickle.dumps(a))
self.assertEqual(a.M, b.M)
self.assertEqual(a.alpha, b.alpha)
self.assertEqual(a.p, b.p)
self.assertEqual(a.m, b.m)
def test_add(self):
s = HyperLogLog(0.05)
for i in range(10):
s.add(str(i))
M = [(i, v) for i, v in enumerate(s.M) if v > 0]
self.assertEqual(M, [(1, 1), (41, 1), (44, 1), (76, 3), (103, 4),
(182, 1), (442, 2), (464, 5), (497, 1), (506, 1)])
def test_hll(self):
m = 16384
f1 = tempfile.NamedTemporaryFile('r+b')
f1.write(''.join('\x00' for i in range(m)))
f1.flush()
mfile1 = mmap.mmap(f1.fileno(), 0)
mslice1 = MmapSlice(mfile1, m, 0)
test = HyperLogLog(0.01, mslice1)
self.assertEqual(len(test), 0)
test.add('test_val')
self.assertEqual(len(test), 1)
def test_3(self):
size = int(1e5)
data = np.random.randint(low=(-1)*int(1e10), high=int(1e10), size=size)
b = int(np.log2(size)) # Num bits needed.
hll = HyperLogLog(hash_fn=hashlib.sha1, num_bits=b)
my_set = set()
for val in data:
hll.add(val)
my_set.add(val)
my_set_n = len(my_set)
hll_n = hll.get_num_distinct()
error_rate = np.abs(float(my_set_n-hll_n)/float(my_set_n+hll_n))
accepted_error_rate = np.abs(standard_error(2**b))
assert(error_rate <= accepted_error_rate)
def test_calc_cardinality(self):
clist = [1, 5, 10, 30, 60, 200, 1000, 10000, 60000]
n = 30
rel_err = 0.05
for card in clist:
s = 0.0
for c in xrange(n):
a = HyperLogLog(rel_err)
for i in xrange(card):
a.add(os.urandom(20))
s += a.card()
z = (float(s) / n - card) / (rel_err * card / math.sqrt(n))
self.assertLess(-1.96, z)
self.assertGreater(1.96, z)
def test_mmap(self):
f = tempfile.TemporaryFile()
m = 16384
flen = m + mmap.PAGESIZE - m % mmap.PAGESIZE
self.assertGreater(flen, m)
f.write(''.join(['\x00' for i in range(flen)]))
fmap = mmap.mmap(f.fileno(), m)
self.assertEqual(len(fmap), m)
mslice = MmapSlice(fmap, m)
hll = HyperLogLog(self.error_rate, mslice)
for v in self.test_data1:
hll.add(v)
self.assertAlmostEqual(self.test_set_size,
len(hll),
delta=self.test_set_size * self.error_rate)
def test_init(self):
s = HyperLogLog(0.05)
self.assertEqual(s.p, 9)
self.assertEqual(s.alpha, 0.7197831133217303)
self.assertEqual(s.m, 512)
self.assertEqual(len(s.M), 512)
def test_update_err(self):
a = HyperLogLog(0.05)
b = HyperLogLog(0.01)
self.assertRaises(ValueError, a.update, b)
