Merge branch 'TheAlgorithms:master' into terminal_velocity

Author: pluto-tofu

data_structures/stacks/infix_to_prefix_conversion.py

@@ -16,6 +16,39 @@
 
 
 def infix_2_postfix(infix):
+    """
+    >>> infix_2_postfix("a+b^c")  # doctest: +NORMALIZE_WHITESPACE
+     Symbol  |  Stack  | Postfix
+    ----------------------------
+       a     |         | a
+       +     | +       | a
+       b     | +       | ab
+       ^     | +^      | ab
+       c     | +^      | abc
+             | +       | abc^
+             |         | abc^+
+    'abc^+'
+    >>> infix_2_postfix("1*((-a)*2+b)")
+    Traceback (most recent call last):
+        ...
+    KeyError: '('
+    >>> infix_2_postfix("")
+     Symbol  |  Stack  | Postfix
+    ----------------------------
+    ''
+    >>> infix_2_postfix("(()")  # doctest: +NORMALIZE_WHITESPACE
+     Symbol  |  Stack  | Postfix
+    ----------------------------
+       (     | (       |
+       (     | ((      |
+       )     | (       |
+             |         | (
+    '('
+    >>> infix_2_postfix("())")
+    Traceback (most recent call last):
+        ...
+    IndexError: list index out of range
+    """
     stack = []
     post_fix = []
     priority = {
@@ -74,6 +107,42 @@ def infix_2_postfix(infix):
 
 
 def infix_2_prefix(infix):
+    """
+    >>> infix_2_prefix("a+b^c")  # doctest: +NORMALIZE_WHITESPACE
+     Symbol  |  Stack  | Postfix
+    ----------------------------
+       c     |         | c
+       ^     | ^       | c
+       b     | ^       | cb
+       +     | +       | cb^
+       a     | +       | cb^a
+             |         | cb^a+
+    '+a^bc'
+
+    >>> infix_2_prefix("1*((-a)*2+b)")
+    Traceback (most recent call last):
+        ...
+    KeyError: '('
+
+    >>> infix_2_prefix('')
+     Symbol  |  Stack  | Postfix
+    ----------------------------
+    ''
+
+    >>> infix_2_prefix('(()')
+    Traceback (most recent call last):
+        ...
+    IndexError: list index out of range
+
+    >>> infix_2_prefix('())')  # doctest: +NORMALIZE_WHITESPACE
+     Symbol  |  Stack  | Postfix
+    ----------------------------
+       (     | (       |
+       (     | ((      |
+       )     | (       |
+             |         | (
+    '('
+    """
     infix = list(infix[::-1])  # reverse the infix equation
 
     for i in range(len(infix)):
@@ -88,6 +157,10 @@ def infix_2_prefix(infix):
 
 
 if __name__ == "__main__":
+    from doctest import testmod
+
+    testmod()
+
     Infix = input("\nEnter an Infix Equation = ")  # Input an Infix equation
     Infix = "".join(Infix.split())  # Remove spaces from the input
     print("\n\t", Infix, "(Infix) -> ", infix_2_prefix(Infix), "(Prefix)")

machine_learning/k_means_clust.py

@@ -235,7 +235,7 @@ def report_generator(
         ]  # group by cluster number
         .agg(
             [
-                ("sum", np.sum),
+                ("sum", "sum"),
                 ("mean_with_zeros", lambda x: np.mean(np.nan_to_num(x))),
                 ("mean_without_zeros", lambda x: x.replace(0, np.NaN).mean()),
                 (
@@ -248,7 +248,7 @@ def report_generator(
                         )
                     ),
                 ),
-                ("mean_with_na", np.mean),
+                ("mean_with_na", "mean"),
                 ("min", lambda x: x.min()),
                 ("5%", lambda x: x.quantile(0.05)),
                 ("25%", lambda x: x.quantile(0.25)),

maths/carmichael_number.py

@@ -10,10 +10,21 @@
 Examples of Carmichael Numbers: 561, 1105, ...
 https://en.wikipedia.org/wiki/Carmichael_number
 """
+
 from maths.greatest_common_divisor import greatest_common_divisor
 
 
 def power(x: int, y: int, mod: int) -> int:
+    """
+
+    Examples:
+    >>> power(2, 15, 3)
+    2
+
+    >>> power(5, 1, 30)
+    5
+    """
+
     if y == 0:
         return 1
     temp = power(x, y // 2, mod) % mod
@@ -24,15 +35,47 @@ def power(x: int, y: int, mod: int) -> int:
 
 
 def is_carmichael_number(n: int) -> bool:
-    b = 2
-    while b < n:
-        if greatest_common_divisor(b, n) == 1 and power(b, n - 1, n) != 1:
-            return False
-        b += 1
-    return True
+    """
+
+    Examples:
+    >>> is_carmichael_number(562)
+    False
+
+    >>> is_carmichael_number(561)
+    True
+
+    >>> is_carmichael_number(5.1)
+    Traceback (most recent call last):
+         ...
+    ValueError: Number 5.1 must instead be a positive integer
+
+    >>> is_carmichael_number(-7)
+    Traceback (most recent call last):
+         ...
+    ValueError: Number -7 must instead be a positive integer
+
+    >>> is_carmichael_number(0)
+    Traceback (most recent call last):
+         ...
+    ValueError: Number 0 must instead be a positive integer
+    """
+
+    if n <= 0 or not isinstance(n, int):
+        msg = f"Number {n} must instead be a positive integer"
+        raise ValueError(msg)
+
+    return all(
+        power(b, n - 1, n) == 1
+        for b in range(2, n)
+        if greatest_common_divisor(b, n) == 1
+    )
 
 
 if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()
+
     number = int(input("Enter number: ").strip())
     if is_carmichael_number(number):
         print(f"{number} is a Carmichael Number.")

maths/primelib.py

@@ -574,6 +574,11 @@ def fib(n):
     """
     input: positive integer 'n'
     returns the n-th fibonacci term , indexing by 0
+
+    >>> fib(5)
+    8
+    >>> fib(99)
+    354224848179261915075
     """
 
     # precondition
@@ -589,3 +594,9 @@ def fib(n):
         fib1 = tmp
 
     return ans
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()