#20 Add real sieve algorithm

nprime/pyprime.py

@@ -116,6 +116,24 @@ def sieve_eratosthenes(upper):
  """
  Implementation of the sieve of erathostenes that discover the primes and their composite up to a limit.
 
+ :return: a dictionary,
+ the key are the primes up to n
+ the value is the list of composites of these primes up to n
+ """
+ primes = {}
+ composites = set()
+ for p in range(2, upper + 1):
+ if p not in composites:
+ primes[p] = range(p * p, upper + 1, p)
+ composites.update(primes[p])
+
+ return primes
+
+
+def trial_division(upper):
+ """
+ Implementation of the trial division that discover the primes and all their divider up to a limit.
+
  :return: a dictionary,
  the key are the primes up to n
  the value is the list of composites of these primes up to n

setup.py

@@ -5,7 +5,7 @@
 LONG_DESCRIPTION = convert("README.md")
 
 setup(name='nprime',
- version='1.0.0',
+ version='1.1.0',
  description='Python library for primes algorithms',
  long_description=LONG_DESCRIPTION,
  author='sylhare',

tests/test_eratosthenes.py

@@ -9,20 +9,21 @@ class TestEratosthenes(unittest.TestCase):
 
  def test_001_is_not_integer_return_error(self):
  """ there should only be 2 in the list, if limit is set to 2 """
- self.assertRaises(ValueError, sieve, 3.8)
+ self.assertRaises(TypeError, sieve, 3.8)
 
  def test_002_is_inferior_to_two_return_error(self):
  """ there should only be 2 in the list, if limit is set to 2 """
- self.assertRaises(ValueError, sieve, -1)
+ self.assertEquals({}, sieve(-1))
 
  def test_003_is_sieve_showing_primes_and_composite(self):
  """ The sieve should work for the first 10 numbers"""
- self.assertTrue(sieve(10) == {2: [4, 6, 8], 3: [6, 9], 5: [], 7: []})
+ self.assertEquals({2: [4, 6, 8, 10], 3: [9], 5: [], 7: []}, sieve(10))
 
- @unittest.skip("Does not work with Travis CI")
  def test_004_are_all_keys_primes(self):
  """ Making sure that all keys from the sieve are prime """
- self.assertTrue(list(sieve(70)) == FIRST_PRIMES)
+ primes = list(sieve(70))
+ primes.sort()
+ self.assertEqual(FIRST_PRIMES, primes)
 
 
 if __name__ == '__main__':

tests/test_trial_division.py

@@ -0,0 +1,30 @@
+import unittest
+
+from nprime.pyprime import trial_division as trial_division
+from tests.prime_testcase import FIRST_PRIMES
+
+
+class TestTrialDivision(unittest.TestCase):
+ """ Tests for generate prime function """
+
+ def test_001_is_not_integer_return_error(self):
+ """ there should only be 2 in the list, if limit is set to 2 """
+ self.assertRaises(ValueError, trial_division, 3.8)
+
+ def test_002_is_inferior_to_two_return_error(self):
+ """ there should only be 2 in the list, if limit is set to 2 """
+ self.assertRaises(ValueError, trial_division, -1)
+
+ def test_003_is_trial_division_showing_primes_and_composite(self):
+ """ The trial_division should work for the first 10 numbers"""
+ self.assertEquals({2: [4, 6, 8], 3: [6, 9], 5: [], 7: []}, trial_division(10))
+
+ def test_004_are_all_keys_primes(self):
+ """ Making sure that all keys from the trial_division are prime """
+ primes = list(trial_division(70).keys())
+ primes.sort()
+ self.assertEqual(FIRST_PRIMES, primes)
+
+
+if __name__ == '__main__':
+ unittest.main()