1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
|
#! /usr/bin/env python
import sys
import os
import tempfile
import pybloomfilter
WORDS_FILE = os.path.join(os.path.dirname(__file__), 'words')
TEST_WORDS = os.path.join(os.path.dirname(__file__), 'testwords')
def main():
global pybloomfilter
if len(sys.argv) > 1 and sys.argv[1].lower() == '-pybloom':
import pybloom
pybloomfilter = pybloom
with open(WORDS_FILE) as base_file:
with open(TEST_WORDS) as test_file:
base_words = set(base_file)
test_words = set(test_file)
correct_overlap = len(base_words & test_words)
num_test_words = len(test_words)
number_words = len(base_words)
for error_rate in (0.01, 0.001, 0.0001):
test_errors(error_rate, number_words, correct_overlap, num_test_words)
def test_errors(error_rate, filter_size, correct_overlap, num_test_words):
bloom_file = tempfile.NamedTemporaryFile()
try:
bf = pybloomfilter.BloomFilter(filter_size, error_rate, bloom_file.name)
except TypeError:
bf = pybloomfilter.BloomFilter(filter_size, error_rate)
with open(WORDS_FILE) as source_file:
with open(TEST_WORDS) as test_file:
run_test(bf, source_file, test_file, correct_overlap, num_test_words, error_rate)
#os.unlink(bloom_file.name)
def run_test(bf, source_file, test_file, correct_overlap, num_test_words, error_rate):
for word in source_file:
bf.add(word.rstrip())
positive_matches = sum(1 for word in test_file
if word.rstrip() in bf)
actual_error_rate = float(positive_matches - correct_overlap) / correct_overlap
print "Specified: %f; Measured: %f; num_hashes: %d, num_bits: %d" % (
error_rate,
actual_error_rate,
bf.num_slices,
bf.num_bits,
)
if __name__ == '__main__':
main()
|
