Added docs, test and format for code

Rodolfo Quispe · Rodolfo Quispe · commit b6d4bb0e5900 · 2019-10-02T12:20:01.000-05:00
diff --git a/allalgorithms/numeric/prime_numbers.py b/allalgorithms/numeric/prime_numbers.py
@@ -21,13 +21,8 @@ def sieve(n):
     return prime
 
 def prime_lower(n):
-    """
-    inputs:
-        n: integer
-
-    outputs: list of prime numbers less or equal than n
-    """
-    assert n>=1 and n<=SIEVE_LIMIT, "input value is not valid"
+    if n < 1 or n > SIEVE_LIMIT:
+        return []
     prime = sieve(n)
     ans = []
     for i in range(n+1):
diff --git a/docs/numeric/prime-numbers.md b/docs/numeric/prime-numbers.md
@@ -0,0 +1,34 @@
+# Prime Numbers
+
+Using prime numbers is common in many problems. We implement various algorithms using them.
+
+## Install
+
+```
+pip install allalgorithms
+```
+
+## Usage
+
+```py
+from allalgorithms.numeric import prime_lower
+
+print(prime_lower(18))
+# -> [2, 3, 5, 7, 11, 13, 17]
+
+print(prime_lower(-1))
+# -> []
+
+print(prime_lower(1000001))
+# -> []
+```
+
+## API
+
+### prime_lower(query)
+
+> Return array of prime numbers lower than `query`, `query` must be lower than `10e6` to avoid memory problems.
+
+##### Params:
+
+- `query`: superior limit for the array of prime number
diff --git a/tests/test_numeric.py b/tests/test_numeric.py
@@ -1,13 +1,22 @@
 import unittest
 
-from allalgorithms.numeric import find_max
-
+from allalgorithms.numeric import (
+    find_max,
+    prime_lower
+)
 
 class TestMax(unittest.TestCase):
 
     def test_find_max_value(self):
         test_list = [3, 1, 8, 7, 4]
         self.assertEqual(8, find_max(test_list))
 
+class TestPrimeLower(unittest.TestCase):
+
+    def test_prime_lower_value(self):
+        test_list =[2, 3, 5, 7, 11, 13, 17]
+        self.assertEqual(prime_lower(18), test_list)
+
+
 if __name__ == "__main__":
     unittest.main()
