Set the Python file maximum line length to 88 characters (#2122)

* flake8 --max-line-length=88

* fixup! Format Python code with psf/black push

Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>

.travis.yml

@@ -10,7 +10,7 @@ notifications:
     on_success: never
 before_script:
   - black --check . || true
-  - flake8 --ignore=E203,W503 --max-complexity=25 --max-line-length=120 --statistics --count .
+  - flake8 --ignore=E203,W503 --max-complexity=25 --max-line-length=88 --statistics --count .
   - scripts/validate_filenames.py  # no uppercase, no spaces, in a directory
   - pip install -r requirements.txt  # fast fail on black, flake8, validate_filenames
 script:

arithmetic_analysis/intersection.py

@@ -1,9 +1,11 @@
 import math
 
 
-def intersection(
-    function, x0, x1
-):  # function is the f we want to find its root and x0 and x1 are two random starting points
+def intersection(function, x0, x1):
+    """
+    function is the f we want to find its root
+    x0 and x1 are two random starting points
+    """
     x_n = x0
     x_n1 = x1
     while True:

backtracking/hamiltonian_cycle.py

@@ -16,8 +16,8 @@ def valid_connection(
     Checks whether it is possible to add next into path by validating 2 statements
     1. There should be path between current and next vertex
     2. Next vertex should not be in path
-    If both validations succeeds we return true saying that it is possible to connect this vertices
-    either we return false
+    If both validations succeeds we return True saying that it is possible to connect
+    this vertices either we return False
 
     Case 1:Use exact graph as in main function, with initialized values
     >>> graph = [[0, 1, 0, 1, 0],
@@ -52,7 +52,8 @@ def util_hamilton_cycle(graph: List[List[int]], path: List[int], curr_ind: int)
     Pseudo-Code
     Base Case:
     1. Chceck if we visited all of vertices
-        1.1 If last visited vertex has path to starting vertex return True either return False
+        1.1 If last visited vertex has path to starting vertex return True either
+            return False
     Recursive Step:
     2. Iterate over each vertex
         Check if next vertex is valid for transiting from current vertex
@@ -74,7 +75,8 @@ def util_hamilton_cycle(graph: List[List[int]], path: List[int], curr_ind: int)
     >>> print(path)
     [0, 1, 2, 4, 3, 0]
 
-    Case 2: Use exact graph as in previous case, but in the properties taken from middle of calculation
+    Case 2: Use exact graph as in previous case, but in the properties taken from
+        middle of calculation
     >>> graph = [[0, 1, 0, 1, 0],
     ...          [1, 0, 1, 1, 1],
     ...          [0, 1, 0, 0, 1],

backtracking/n_queens.py

@@ -12,8 +12,8 @@ solution = []
 
 def isSafe(board, row, column):
     """
-    This function returns a boolean value True if it is safe to place a queen there considering
-    the current state of the board.
+    This function returns a boolean value True if it is safe to place a queen there
+    considering the current state of the board.
 
     Parameters :
     board(2D matrix) : board
@@ -56,8 +56,8 @@ def solve(board, row):
         return
     for i in range(len(board)):
         """
-        For every row it iterates through each column to check if it is feasible to place a
-        queen there.
+        For every row it iterates through each column to check if it is feasible to
+        place a queen there.
         If all the combinations for that particular branch are successful the board is
         reinitialized for the next possible combination.
         """

backtracking/sum_of_subsets.py

@@ -1,9 +1,10 @@
 """
-        The sum-of-subsetsproblem states that a set of non-negative integers, and a value M,
-        determine all possible subsets of the given set whose summation sum equal to given M.
+        The sum-of-subsetsproblem states that a set of non-negative integers, and a
+        value M, determine all possible subsets of the given set whose summation sum
+        equal to given M.
 
-        Summation of the chosen numbers must be equal to given number M and one number can
-        be used only once.
+        Summation of the chosen numbers must be equal to given number M and one number
+        can be used only once.
 """
 
 
@@ -21,7 +22,8 @@ def create_state_space_tree(nums, max_sum, num_index, path, result, remaining_nu
         Creates a state space tree to iterate through each branch using DFS.
         It terminates the branching of a node when any of the two conditions
         given below satisfy.
-        This algorithm follows depth-fist-search and backtracks when the node is not branchable.
+        This algorithm follows depth-fist-search and backtracks when the node is not
+        branchable.
 
         """
     if sum(path) > max_sum or (remaining_nums_sum + sum(path)) < max_sum:

blockchain/chinese_remainder_theorem.py

@@ -1,8 +1,9 @@
 # Chinese Remainder Theorem:
 # GCD ( Greatest Common Divisor ) or HCF ( Highest Common Factor )
 
-# If GCD(a,b) = 1, then for any remainder ra modulo a and any remainder rb modulo b there exists integer n,
-# such that n = ra (mod a) and n = ra(mod b).  If n1 and n2 are two such integers, then n1=n2(mod ab)
+# If GCD(a,b) = 1, then for any remainder ra modulo a and any remainder rb modulo b
+# there exists integer n, such that n = ra (mod a) and n = ra(mod b).  If n1 and n2 are
+# two such integers, then n1=n2(mod ab)
 
 # Algorithm :
 

blockchain/diophantine_equation.py

@@ -1,5 +1,6 @@
-# Diophantine Equation : Given integers a,b,c ( at least one of a and b != 0), the diophantine equation
-# a*x + b*y = c has a solution (where x and y are integers) iff gcd(a,b) divides c.
+# Diophantine Equation : Given integers a,b,c ( at least one of a and b != 0), the
+# diophantine equation a*x + b*y = c has a solution (where x and y are integers)
+# iff gcd(a,b) divides c.
 
 # GCD ( Greatest Common Divisor ) or HCF ( Highest Common Factor )
 
@@ -29,8 +30,9 @@ def diophantine(a, b, c):
 
 # Finding All solutions of Diophantine Equations:
 
-# Theorem : Let gcd(a,b) = d, a = d*p, b = d*q. If (x0,y0) is a solution of Diophantine Equation a*x + b*y = c.
-# a*x0 + b*y0 = c, then all the solutions have the form a(x0 + t*q) + b(y0 - t*p) = c, where t is an arbitrary integer.
+# Theorem : Let gcd(a,b) = d, a = d*p, b = d*q. If (x0,y0) is a solution of Diophantine
+# Equation a*x + b*y = c.  a*x0 + b*y0 = c, then all the solutions have the form
+# a(x0 + t*q) + b(y0 - t*p) = c, where t is an arbitrary integer.
 
 # n is the number of solution you want, n = 2 by default
 
@@ -75,8 +77,9 @@ def greatest_common_divisor(a, b):
     >>> greatest_common_divisor(7,5)
     1
 
-    Note : In number theory, two integers a and b are said to be relatively prime, mutually prime, or co-prime
-           if the only positive integer (factor) that divides both of them is 1  i.e., gcd(a,b) = 1.
+    Note : In number theory, two integers a and b are said to be relatively prime,
+           mutually prime, or co-prime if the only positive integer (factor) that
+           divides both of them is 1  i.e., gcd(a,b) = 1.
 
     >>> greatest_common_divisor(121, 11)
     11
@@ -91,7 +94,8 @@ def greatest_common_divisor(a, b):
     return b
 
 
-# Extended Euclid's Algorithm : If d divides a and b and d = a*x + b*y for integers x and y, then d = gcd(a,b)
+# Extended Euclid's Algorithm : If d divides a and b and d = a*x + b*y for integers
+# x and y, then d = gcd(a,b)
 
 
 def extended_gcd(a, b):

blockchain/modular_division.py

@@ -3,8 +3,8 @@
 
 # GCD ( Greatest Common Divisor ) or HCF ( Highest Common Factor )
 
-# Given three integers a, b, and n, such that gcd(a,n)=1 and n>1, the algorithm should return an integer x such that
-#        0≤x≤n−1, and  b/a=x(modn) (that is, b=ax(modn)).
+# Given three integers a, b, and n, such that gcd(a,n)=1 and n>1, the algorithm should
+# return an integer x such that 0≤x≤n−1, and  b/a=x(modn) (that is, b=ax(modn)).
 
 # Theorem:
 # a has a multiplicative inverse modulo n iff gcd(a,n) = 1
@@ -68,7 +68,8 @@ def modular_division2(a, b, n):
     return x
 
 
-# Extended Euclid's Algorithm : If d divides a and b and d = a*x + b*y for integers x and y, then d = gcd(a,b)
+# Extended Euclid's Algorithm : If d divides a and b and d = a*x + b*y for integers x
+# and y, then d = gcd(a,b)
 
 
 def extended_gcd(a, b):
@@ -123,8 +124,9 @@ def greatest_common_divisor(a, b):
     >>> greatest_common_divisor(7,5)
     1
 
-    Note : In number theory, two integers a and b are said to be relatively prime, mutually prime, or co-prime
-           if the only positive integer (factor) that divides both of them is 1  i.e., gcd(a,b) = 1.
+    Note : In number theory, two integers a and b are said to be relatively prime,
+        mutually prime, or co-prime if the only positive integer (factor) that divides
+        both of them is 1  i.e., gcd(a,b) = 1.
 
     >>> greatest_common_divisor(121, 11)
     11

ciphers/affine_cipher.py

@@ -55,7 +55,8 @@ def check_keys(keyA, keyB, mode):
 
 def encrypt_message(key: int, message: str) -> str:
     """
-    >>> encrypt_message(4545, 'The affine cipher is a type of monoalphabetic substitution cipher.')
+    >>> encrypt_message(4545, 'The affine cipher is a type of monoalphabetic '
+    ...                       'substitution cipher.')
     'VL}p MM{I}p~{HL}Gp{vp pFsH}pxMpyxIx JHL O}F{~pvuOvF{FuF{xIp~{HL}Gi'
     """
     keyA, keyB = divmod(key, len(SYMBOLS))
@@ -72,7 +73,8 @@ def encrypt_message(key: int, message: str) -> str:
 
 def decrypt_message(key: int, message: str) -> str:
     """
-    >>> decrypt_message(4545, 'VL}p MM{I}p~{HL}Gp{vp pFsH}pxMpyxIx JHL O}F{~pvuOvF{FuF{xIp~{HL}Gi')
+    >>> decrypt_message(4545, 'VL}p MM{I}p~{HL}Gp{vp pFsH}pxMpyxIx JHL O}F{~pvuOvF{FuF'
+    ...                       '{xIp~{HL}Gi')
     'The affine cipher is a type of monoalphabetic substitution cipher.'
     """
     keyA, keyB = divmod(key, len(SYMBOLS))

ciphers/base64_cipher.py

@@ -39,7 +39,8 @@ def decode_base64(text):
     'WELCOME to base64 encoding 😁'
     >>> decode_base64('QcOF4ZCD8JCAj/CfpJM=')
     'AÅᐃ𐀏🤓'
-    >>> decode_base64("QUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFB\r\nQUFB")
+    >>> decode_base64("QUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUFBQUF"
+    ...               "BQUFBQUFBQUFB\r\nQUFB")
     'AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA'
     """
     base64_chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"

ciphers/elgamal_key_generator.py

@@ -16,7 +16,8 @@ def main():
 
 # I have written my code naively same as definition of primitive root
 # however every time I run this program, memory exceeded...
-# so I used 4.80 Algorithm in Handbook of Applied Cryptography(CRC Press, ISBN : 0-8493-8523-7, October 1996)
+# so I used 4.80 Algorithm in
+# Handbook of Applied Cryptography(CRC Press, ISBN : 0-8493-8523-7, October 1996)
 # and it seems to run nicely!
 def primitiveRoot(p_val):
     print("Generating primitive root of p")

ciphers/hill_cipher.py

@@ -106,7 +106,8 @@ class HillCipher:
         req_l = len(self.key_string)
         if greatest_common_divisor(det, len(self.key_string)) != 1:
             raise ValueError(
-                f"determinant modular {req_l} of encryption key({det}) is not co prime w.r.t {req_l}.\nTry another key."
+                f"determinant modular {req_l} of encryption key({det}) is not co prime "
+                f"w.r.t {req_l}.\nTry another key."
             )
 
     def process_text(self, text: str) -> str:

ciphers/shuffled_shift_cipher.py

@@ -83,19 +83,21 @@ class ShuffledShiftCipher:
         Shuffling only 26 letters of the english alphabet can generate 26!
         combinations for the shuffled list. In the program we consider, a set of
         97 characters (including letters, digits, punctuation and whitespaces),
-        thereby creating a possibility of 97! combinations (which is a 152 digit number in itself),
-        thus diminishing the possibility of a brute force approach. Moreover,
-        shift keys even introduce a multiple of 26 for a brute force approach
+        thereby creating a possibility of 97! combinations (which is a 152 digit number
+        in itself), thus diminishing the possibility of a brute force approach.
+        Moreover, shift keys even introduce a multiple of 26 for a brute force approach
         for each of the already 97! combinations.
         """
-        # key_list_options contain nearly all printable except few elements from string.whitespace
+        # key_list_options contain nearly all printable except few elements from
+        # string.whitespace
         key_list_options = (
             string.ascii_letters + string.digits + string.punctuation + " \t\n"
         )
 
         keys_l = []
 
-        # creates points known as breakpoints to break the key_list_options at those points and pivot each substring
+        # creates points known as breakpoints to break the key_list_options at those
+        # points and pivot each substring
         breakpoints = sorted(set(self.__passcode))
         temp_list = []
 
@@ -103,7 +105,8 @@ class ShuffledShiftCipher:
         for i in key_list_options:
             temp_list.extend(i)
 
-            # checking breakpoints at which to pivot temporary sublist and add it into keys_l
+            # checking breakpoints at which to pivot temporary sublist and add it into
+            # keys_l
             if i in breakpoints or i == key_list_options[-1]:
                 keys_l.extend(temp_list[::-1])
                 temp_list = []
@@ -131,7 +134,8 @@ class ShuffledShiftCipher:
         """
         decoded_message = ""
 
-        # decoding shift like Caesar cipher algorithm implementing negative shift or reverse shift or left shift
+        # decoding shift like Caesar cipher algorithm implementing negative shift or
+        # reverse shift or left shift
         for i in encoded_message:
             position = self.__key_list.index(i)
             decoded_message += self.__key_list[
@@ -152,7 +156,8 @@ class ShuffledShiftCipher:
         """
         encoded_message = ""
 
-        # encoding shift like Caesar cipher algorithm implementing positive shift or forward shift or right shift
+        # encoding shift like Caesar cipher algorithm implementing positive shift or
+        # forward shift or right shift
         for i in plaintext:
             position = self.__key_list.index(i)
             encoded_message += self.__key_list[

compression/peak_signal_to_noise_ratio.py

@@ -1,6 +1,8 @@
 """
-        Peak signal-to-noise ratio - PSNR - https://en.wikipedia.org/wiki/Peak_signal-to-noise_ratio
-    Source: https://tutorials.techonical.com/how-to-calculate-psnr-value-of-two-images-using-python/
+Peak signal-to-noise ratio - PSNR
+    https://en.wikipedia.org/wiki/Peak_signal-to-noise_ratio
+Source:
+https://tutorials.techonical.com/how-to-calculate-psnr-value-of-two-images-using-python
 """
 
 import math

conversions/decimal_to_any.py

@@ -66,9 +66,10 @@ def decimal_to_any(num: int, base: int) -> str:
     if base > 36:
         raise ValueError("base must be <= 36")
     # fmt: off
-    ALPHABET_VALUES = {'10': 'A', '11': 'B', '12': 'C', '13': 'D', '14': 'E', '15': 'F', '16': 'G', '17': 'H',
-                       '18': 'I', '19': 'J', '20': 'K', '21': 'L', '22': 'M', '23': 'N', '24': 'O', '25': 'P',
-                       '26': 'Q', '27': 'R', '28': 'S', '29': 'T', '30': 'U', '31': 'V', '32': 'W', '33': 'X',
+    ALPHABET_VALUES = {'10': 'A', '11': 'B', '12': 'C', '13': 'D', '14': 'E', '15': 'F',
+                       '16': 'G', '17': 'H', '18': 'I', '19': 'J', '20': 'K', '21': 'L',
+                       '22': 'M', '23': 'N', '24': 'O', '25': 'P', '26': 'Q', '27': 'R',
+                       '28': 'S', '29': 'T', '30': 'U', '31': 'V', '32': 'W', '33': 'X',
                        '34': 'Y', '35': 'Z'}
     # fmt: on
     new_value = ""

conversions/decimal_to_hexadecimal.py

@@ -23,7 +23,8 @@ values = {
 
 def decimal_to_hexadecimal(decimal):
     """
-        take integer decimal value, return hexadecimal representation as str beginning with 0x
+        take integer decimal value, return hexadecimal representation as str beginning
+        with 0x
         >>> decimal_to_hexadecimal(5)
         '0x5'
         >>> decimal_to_hexadecimal(15)

conversions/decimal_to_octal.py

@@ -9,7 +9,8 @@ import math
 def decimal_to_octal(num: int) -> str:
     """Convert a Decimal Number to an Octal Number.
 
-    >>> all(decimal_to_octal(i) == oct(i) for i in (0, 2, 8, 64, 65, 216, 255, 256, 512))
+    >>> all(decimal_to_octal(i) == oct(i) for i
+    ...     in (0, 2, 8, 64, 65, 216, 255, 256, 512))
     True
     """
     octal = 0

data_structures/data_structures/heap/heap_generic.py

@@ -1,5 +1,7 @@
 class Heap:
-    """A generic Heap class, can be used as min or max by passing the key function accordingly.
+    """
+    A generic Heap class, can be used as min or max by passing the key function
+    accordingly.
     """
 
     def __init__(self, key=None):
@@ -9,7 +11,8 @@ class Heap:
         self.pos_map = {}
         # Stores current size of heap.
         self.size = 0
-        # Stores function used to evaluate the score of an item on which basis ordering will be done.
+        # Stores function used to evaluate the score of an item on which basis ordering
+        # will be done.
         self.key = key or (lambda x: x)
 
     def _parent(self, i):
@@ -41,7 +44,10 @@ class Heap:
         return self.arr[i][1] < self.arr[j][1]
 
     def _get_valid_parent(self, i):
-        """Returns index of valid parent as per desired ordering among given index and both it's children"""
+        """
+        Returns index of valid parent as per desired ordering among given index and
+        both it's children
+        """
         left = self._left(i)
         right = self._right(i)
         valid_parent = i
@@ -87,8 +93,8 @@ class Heap:
         self.arr[index] = self.arr[self.size - 1]
         self.pos_map[self.arr[self.size - 1][0]] = index
         self.size -= 1
-        # Make sure heap is right in both up and down direction.
-        # Ideally only one of them will make any change- so no performance loss in calling both.
+        # Make sure heap is right in both up and down direction. Ideally only one
+        # of them will make any change- so no performance loss in calling both.
         if self.size > index:
             self._heapify_up(index)
             self._heapify_down(index)
@@ -109,7 +115,10 @@ class Heap:
         return self.arr[0] if self.size else None
 
     def extract_top(self):
-        """Returns top item tuple (Calculated value, item) from heap and removes it as well if present"""
+        """
+        Return top item tuple (Calculated value, item) from heap and removes it as well
+        if present
+        """
         top_item_tuple = self.get_top()
         if top_item_tuple:
             self.delete_item(top_item_tuple[0])

data_structures/linked_list/skip_list.py

@@ -126,7 +126,8 @@ class SkipList(Generic[KT, VT]):
         """
         :param key: Searched key,
         :return: Tuple with searched node (or None if given key is not present)
-                 and list of nodes that refer (if key is present) of should refer to given node.
+                 and list of nodes that refer (if key is present) of should refer to
+                 given node.
         """
 
         # Nodes with refer or should refer to output node
@@ -141,7 +142,8 @@ class SkipList(Generic[KT, VT]):
             #                             in skipping searched key.
             while i < node.level and node.forward[i].key < key:
                 node = node.forward[i]
-            # Each leftmost node (relative to searched node) will potentially have to be updated.
+            # Each leftmost node (relative to searched node) will potentially have to
+            # be updated.
             update_vector.append(node)
 
         update_vector.reverse()  # Note that we were inserting values in reverse order.

data_structures/stacks/infix_to_prefix_conversion.py

@@ -49,10 +49,8 @@ def infix_2_postfix(Infix):
         else:
             if len(Stack) == 0:
                 Stack.append(x)  # If stack is empty, push x to stack
-            else:
-                while (
-                    len(Stack) > 0 and priority[x] <= priority[Stack[-1]]
-                ):  # while priority of x is not greater than priority of element in the stack
+            else:  # while priority of x is not > priority of element in the stack
+                while len(Stack) > 0 and priority[x] <= priority[Stack[-1]]:
                     Postfix.append(Stack.pop())  # pop stack & add to Postfix
                 Stack.append(x)  # push x to stack
 

data_structures/trie/trie.py

@@ -1,8 +1,8 @@
 """
 A Trie/Prefix Tree is a kind of search tree used to provide quick lookup
 of words/patterns in a set of words. A basic Trie however has O(n^2) space complexity
-making it impractical in practice. It however provides O(max(search_string, length of longest word))
-lookup time making it an optimal approach when space is not an issue.
+making it impractical in practice. It however provides O(max(search_string, length of
+longest word)) lookup time making it an optimal approach when space is not an issue.
 """
 
 

digital_image_processing/edge_detection/canny.py

@@ -29,8 +29,9 @@ def canny(image, threshold_low=15, threshold_high=30, weak=128, strong=255):
     dst = np.zeros((image_row, image_col))
 
     """
-    Non-maximum suppression. If the edge strength of the current pixel is the largest compared to the other pixels
-    in the mask with the same direction, the value will be preserved. Otherwise, the value will be suppressed.
+    Non-maximum suppression. If the edge strength of the current pixel is the largest
+    compared to the other pixels in the mask with the same direction, the value will be
+    preserved. Otherwise, the value will be suppressed.
     """
     for row in range(1, image_row - 1):
         for col in range(1, image_col - 1):
@@ -71,10 +72,12 @@ def canny(image, threshold_low=15, threshold_high=30, weak=128, strong=255):
                     dst[row, col] = sobel_grad[row, col]
 
             """
-            High-Low threshold detection. If an edge pixel’s gradient value is higher than the high threshold
-            value, it is marked as a strong edge pixel. If an edge pixel’s gradient value is smaller than the high
-            threshold value and larger than the low threshold value, it is marked as a weak edge pixel. If an edge
-            pixel's value is smaller than the low threshold value, it will be suppressed.
+            High-Low threshold detection. If an edge pixel’s gradient value is higher
+            than the high threshold value, it is marked as a strong edge pixel. If an
+            edge pixel’s gradient value is smaller than the high threshold value and
+            larger than the low threshold value, it is marked as a weak edge pixel. If
+            an edge pixel's value is smaller than the low threshold value, it will be
+            suppressed.
             """
             if dst[row, col] >= threshold_high:
                 dst[row, col] = strong
@@ -84,9 +87,10 @@ def canny(image, threshold_low=15, threshold_high=30, weak=128, strong=255):
                 dst[row, col] = weak
 
     """
-    Edge tracking. Usually a weak edge pixel caused from true edges will be connected to a strong edge pixel while
-    noise responses are unconnected. As long as there is one strong edge pixel that is involved in its 8-connected
-    neighborhood, that weak edge point can be identified as one that should be preserved.
+    Edge tracking. Usually a weak edge pixel caused from true edges will be connected
+    to a strong edge pixel while noise responses are unconnected. As long as there is
+    one strong edge pixel that is involved in its 8-connected neighborhood, that weak
+    edge point can be identified as one that should be preserved.
     """
     for row in range(1, image_row):
         for col in range(1, image_col):

digital_image_processing/resize/resize.py

@@ -36,7 +36,8 @@ class NearestNeighbour:
         Get parent X coordinate for destination X
         :param x: Destination X coordinate
         :return: Parent X coordinate based on `x ratio`
-        >>> nn = NearestNeighbour(imread("digital_image_processing/image_data/lena.jpg", 1), 100, 100)
+        >>> nn = NearestNeighbour(imread("digital_image_processing/image_data/lena.jpg",
+        ...                              1), 100, 100)
         >>> nn.ratio_x = 0.5
         >>> nn.get_x(4)
         2
@@ -48,7 +49,8 @@ class NearestNeighbour:
         Get parent Y coordinate for destination Y
         :param y: Destination X coordinate
         :return: Parent X coordinate based on `y ratio`
-        >>> nn = NearestNeighbour(imread("digital_image_processing/image_data/lena.jpg", 1), 100, 100)
+        >>> nn = NearestNeighbour(imread("digital_image_processing/image_data/lena.jpg",
+                                         1), 100, 100)
         >>> nn.ratio_y = 0.5
         >>> nn.get_y(4)
         2

digital_image_processing/sepia.py

@@ -6,7 +6,10 @@ from cv2 import imread, imshow, waitKey, destroyAllWindows
 
 
 def make_sepia(img, factor: int):
-    """ Function create sepia tone. Source: https://en.wikipedia.org/wiki/Sepia_(color) """
+    """
+    Function create sepia tone.
+    Source: https://en.wikipedia.org/wiki/Sepia_(color)
+    """
     pixel_h, pixel_v = img.shape[0], img.shape[1]
 
     def to_grayscale(blue, green, red):

divide_and_conquer/convex_hull.py

@@ -140,7 +140,8 @@ def _validate_input(points):
 
     Exception
     ---------
-    ValueError: if points is empty or None, or if a wrong data structure like a scalar is passed
+    ValueError: if points is empty or None, or if a wrong data structure like a scalar
+                 is passed
 
     TypeError: if an iterable but non-indexable object (eg. dictionary) is passed.
                 The exception to this a set which we'll convert to a list before using
@@ -229,10 +230,10 @@ def convex_hull_bf(points):
     """
     Constructs the convex hull of a set of 2D points using a brute force algorithm.
     The algorithm basically considers all combinations of points (i, j) and uses the
-    definition of convexity to determine whether (i, j) is part of the convex hull or not.
-    (i, j) is part of the convex hull if and only iff there are no points on both sides
-    of the line segment connecting the ij, and there is no point k such that k is on either end
-    of the ij.
+    definition of convexity to determine whether (i, j) is part of the convex hull or
+    not.  (i, j) is part of the convex hull if and only iff there are no points on both
+    sides of the line segment connecting the ij, and there is no point k such that k is
+    on either end of the ij.
 
     Runtime: O(n^3) - definitely horrible
 
@@ -255,9 +256,11 @@ def convex_hull_bf(points):
      [(0.0, 0.0), (1.0, 0.0), (10.0, 1.0)]
      >>> convex_hull_bf([[0, 0], [1, 0], [10, 0]])
      [(0.0, 0.0), (10.0, 0.0)]
-     >>> convex_hull_bf([[-1, 1],[-1, -1], [0, 0], [0.5, 0.5], [1, -1], [1, 1], [-0.75, 1]])
+     >>> convex_hull_bf([[-1, 1],[-1, -1], [0, 0], [0.5, 0.5], [1, -1], [1, 1],
+     ...                 [-0.75, 1]])
      [(-1.0, -1.0), (-1.0, 1.0), (1.0, -1.0), (1.0, 1.0)]
-     >>> convex_hull_bf([(0, 3), (2, 2), (1, 1), (2, 1), (3, 0), (0, 0), (3, 3), (2, -1), (2, -4), (1, -3)])
+     >>> convex_hull_bf([(0, 3), (2, 2), (1, 1), (2, 1), (3, 0), (0, 0), (3, 3),
+     ...                 (2, -1), (2, -4), (1, -3)])
      [(0.0, 0.0), (0.0, 3.0), (1.0, -3.0), (2.0, -4.0), (3.0, 0.0), (3.0, 3.0)]
     """
 
@@ -299,9 +302,10 @@ def convex_hull_bf(points):
 def convex_hull_recursive(points):
     """
     Constructs the convex hull of a set of 2D points using a divide-and-conquer strategy
-    The algorithm exploits the geometric properties of the problem by repeatedly partitioning
-    the set of points into smaller hulls, and finding the convex hull of these smaller hulls.
-    The union of the convex hull from smaller hulls is the solution to the convex hull of the larger problem.
+    The algorithm exploits the geometric properties of the problem by repeatedly
+    partitioning the set of points into smaller hulls, and finding the convex hull of
+    these smaller hulls.  The union of the convex hull from smaller hulls is the
+    solution to the convex hull of the larger problem.
 
     Parameter
     ---------
@@ -320,9 +324,11 @@ def convex_hull_recursive(points):
     [(0.0, 0.0), (1.0, 0.0), (10.0, 1.0)]
     >>> convex_hull_recursive([[0, 0], [1, 0], [10, 0]])
     [(0.0, 0.0), (10.0, 0.0)]
-    >>> convex_hull_recursive([[-1, 1],[-1, -1], [0, 0], [0.5, 0.5], [1, -1], [1, 1], [-0.75, 1]])
+    >>> convex_hull_recursive([[-1, 1],[-1, -1], [0, 0], [0.5, 0.5], [1, -1], [1, 1],
+                               [-0.75, 1]])
     [(-1.0, -1.0), (-1.0, 1.0), (1.0, -1.0), (1.0, 1.0)]
-    >>> convex_hull_recursive([(0, 3), (2, 2), (1, 1), (2, 1), (3, 0), (0, 0), (3, 3), (2, -1), (2, -4), (1, -3)])
+    >>> convex_hull_recursive([(0, 3), (2, 2), (1, 1), (2, 1), (3, 0), (0, 0), (3, 3),
+                               (2, -1), (2, -4), (1, -3)])
     [(0.0, 0.0), (0.0, 3.0), (1.0, -3.0), (2.0, -4.0), (3.0, 0.0), (3.0, 3.0)]
 
     """
@@ -335,10 +341,12 @@ def convex_hull_recursive(points):
     # use these two anchors to divide all the points into two hulls,
     # an upper hull and a lower hull.
 
-    # all points to the left (above) the line joining the extreme points belong to the upper hull
-    # all points to the right (below) the line joining the extreme points below to the lower hull
-    # ignore all points on the line joining the extreme points since they cannot be part of the
-    # convex hull
+    # all points to the left (above) the line joining the extreme points belong to the
+    # upper hull
+    # all points to the right (below) the line joining the extreme points below to the
+    # lower hull
+    # ignore all points on the line joining the extreme points since they cannot be
+    # part of the convex hull
 
     left_most_point = points[0]
     right_most_point = points[n - 1]
@@ -366,10 +374,12 @@ def _construct_hull(points, left, right, convex_set):
 
     Parameters
     ---------
-    points: list or None, the hull of points from which to choose the next convex-hull point
+    points: list or None, the hull of points from which to choose the next convex-hull
+        point
     left: Point, the point to the left  of line segment joining left and right
     right: The point to the right of the line segment joining left and right
-    convex_set: set, the current convex-hull. The state of convex-set gets updated by this function
+    convex_set: set, the current convex-hull. The state of convex-set gets updated by
+        this function
 
     Note
     ----

dynamic_programming/fibonacci.py

@@ -1,5 +1,6 @@
 """
-This is a pure Python implementation of Dynamic Programming solution to the fibonacci sequence problem.
+This is a pure Python implementation of Dynamic Programming solution to the fibonacci
+sequence problem.
 """
 
 

dynamic_programming/integer_partition.py

@@ -1,7 +1,8 @@
 """
-The number of partitions of a number n into at least k parts equals the number of partitions into exactly k parts
-plus the number of partitions into at least k-1 parts. Subtracting 1 from each part of a partition of n into k parts
-gives a partition of n-k into k parts. These two facts together are used for this algorithm.
+The number of partitions of a number n into at least k parts equals the number of
+partitions into exactly k parts plus the number of partitions into at least k-1 parts.
+Subtracting 1 from each part of a partition of n into k parts gives a partition of n-k
+into k parts. These two facts together are used for this algorithm.
 """
 
 

dynamic_programming/iterating_through_submasks.py

@@ -12,7 +12,8 @@ def list_of_submasks(mask: int) -> List[int]:
 
     """
     Args:
-        mask : number which shows mask ( always integer > 0, zero does not have any submasks )
+        mask : number which shows mask ( always integer > 0, zero does not have any
+            submasks )
 
     Returns:
         all_submasks : the list of submasks of mask (mask s is called submask of mask

dynamic_programming/knapsack.py

@@ -9,8 +9,8 @@ Note that only the integer weights 0-1 knapsack problem is solvable
 
 def MF_knapsack(i, wt, val, j):
     """
-    This code involves the concept of memory functions. Here we solve the subproblems which are needed
-    unlike the below example
+    This code involves the concept of memory functions. Here we solve the subproblems
+    which are needed unlike the below example
     F is a 2D array with -1s filled up
     """
     global F  # a global dp table for knapsack

dynamic_programming/longest_common_subsequence.py

@@ -1,6 +1,7 @@
 """
-LCS Problem Statement: Given two sequences, find the length of longest subsequence present in both of them.
-A subsequence is a sequence that appears in the same relative order, but not necessarily continuous.
+LCS Problem Statement: Given two sequences, find the length of longest subsequence
+present in both of them.  A subsequence is a sequence that appears in the same relative
+order, but not necessarily continuous.
 Example:"abc", "abg" are subsequences of "abcdefgh".
 """
 

dynamic_programming/longest_sub_array.py

@@ -1,10 +1,12 @@
 """
 Author  : Yvonne
 
-This is a pure Python implementation of Dynamic Programming solution to the longest_sub_array problem.
+This is a pure Python implementation of Dynamic Programming solution to the
+    longest_sub_array problem.
 
 The problem is  :
-Given an array, to find the longest and continuous sub array and get the max sum of the sub array in the given array.
+Given an array, to find the longest and continuous sub array and get the max sum of the
+    sub array in the given array.
 """
 
 

dynamic_programming/rod_cutting.py

@@ -13,8 +13,9 @@ pieces separately or not cutting it at all if the price of it is the maximum obt
 
 def naive_cut_rod_recursive(n: int, prices: list):
     """
-        Solves the rod-cutting problem via naively without using the benefit of dynamic programming.
-        The results is the same sub-problems are solved several times leading to an exponential runtime
+        Solves the rod-cutting problem via naively without using the benefit of dynamic
+        programming. The results is the same sub-problems are solved several times
+        leading to an exponential runtime
 
         Runtime: O(2^n)
 
@@ -26,7 +27,8 @@ def naive_cut_rod_recursive(n: int, prices: list):
 
         Returns
         -------
-        The maximum revenue obtainable for a rod of length n given the list of prices for each piece.
+        The maximum revenue obtainable for a rod of length n given the list of prices
+        for each piece.
 
         Examples
         --------
@@ -50,8 +52,9 @@ def naive_cut_rod_recursive(n: int, prices: list):
 
 def top_down_cut_rod(n: int, prices: list):
     """
-        Constructs a top-down dynamic programming solution for the rod-cutting problem
-        via memoization. This function serves as a wrapper for _top_down_cut_rod_recursive
+        Constructs a top-down dynamic programming solution for the rod-cutting
+        problem via memoization. This function serves as a wrapper for
+        _top_down_cut_rod_recursive
 
         Runtime: O(n^2)
 
@@ -63,12 +66,13 @@ def top_down_cut_rod(n: int, prices: list):
 
         Note
         ----
-        For convenience and because Python's lists using 0-indexing, length(max_rev) = n + 1,
-        to accommodate for the revenue obtainable from a rod of length 0.
+        For convenience and because Python's lists using 0-indexing, length(max_rev) =
+        n + 1, to accommodate for the revenue obtainable from a rod of length 0.
 
         Returns
         -------
-        The maximum revenue obtainable for a rod of length n given the list of prices for each piece.
+        The maximum revenue obtainable for a rod of length n given the list of prices
+        for each piece.
 
         Examples
         -------
@@ -99,7 +103,8 @@ def _top_down_cut_rod_recursive(n: int, prices: list, max_rev: list):
 
         Returns
         -------
-        The maximum revenue obtainable for a rod of length n given the list of prices for each piece.
+        The maximum revenue obtainable for a rod of length n given the list of prices
+        for each piece.
         """
     if max_rev[n] >= 0:
         return max_rev[n]
@@ -144,7 +149,8 @@ def bottom_up_cut_rod(n: int, prices: list):
         """
     _enforce_args(n, prices)
 
-    # length(max_rev) = n + 1, to accommodate for the revenue obtainable from a rod of length 0.
+    # length(max_rev) = n + 1, to accommodate for the revenue obtainable from a rod of
+    # length 0.
     max_rev = [float("-inf") for _ in range(n + 1)]
     max_rev[0] = 0
 
@@ -167,7 +173,8 @@ def _enforce_args(n: int, prices: list):
 
         Throws ValueError:
 
-        if n is negative or there are fewer items in the price list than the length of the rod
+        if n is negative or there are fewer items in the price list than the length of
+        the rod
         """
     if n < 0:
         raise ValueError(f"n must be greater than or equal to 0. Got n = {n}")

dynamic_programming/subset_generation.py

@@ -1,4 +1,4 @@
-# Python program to print all subset combinations of n element in given set of r element.
+# Print all subset combinations of n element in given set of r element.
 
 
 def combination_util(arr, n, r, index, data, i):

dynamic_programming/sum_of_subset.py

@@ -9,7 +9,8 @@ def isSumSubset(arr, arrLen, requiredSum):
     # initially no subsets can be formed hence False/0
     subset = [[False for i in range(requiredSum + 1)] for i in range(arrLen + 1)]
 
-    # for each arr value, a sum of zero(0) can be formed by not taking any element hence True/1
+    # for each arr value, a sum of zero(0) can be formed by not taking any element
+    # hence True/1
     for i in range(arrLen + 1):
         subset[i][0] = True
 

fuzzy_logic/fuzzy_operations.py

@@ -14,7 +14,8 @@ if __name__ == "__main__":
     # Create universe of discourse in Python using linspace ()
     X = np.linspace(start=0, stop=75, num=75, endpoint=True, retstep=False)
 
-    # Create two fuzzy sets by defining any membership function (trapmf(), gbellmf(),gaussmf(), etc).
+    # Create two fuzzy sets by defining any membership function
+    # (trapmf(), gbellmf(), gaussmf(), etc).
     abc1 = [0, 25, 50]
     abc2 = [25, 50, 75]
     young = fuzz.membership.trimf(X, abc1)

geodesy/lamberts_ellipsoidal_distance.py

@@ -11,15 +11,16 @@ def lamberts_ellipsoidal_distance(
     two points on the surface of earth given longitudes and latitudes
     https://en.wikipedia.org/wiki/Geographical_distance#Lambert's_formula_for_long_lines
 
-    NOTE: This algorithm uses geodesy/haversine_distance.py to compute central angle, sigma
+    NOTE: This algorithm uses geodesy/haversine_distance.py to compute central angle,
+        sigma
 
-    Representing the earth as an ellipsoid allows us to approximate distances between points
-    on the surface much better than a sphere. Ellipsoidal formulas treat the Earth as an
-    oblate ellipsoid which means accounting for the flattening that happens at the North
-    and South poles. Lambert's formulae provide accuracy on the order of 10 meteres over
-    thousands of kilometeres. Other methods can provide millimeter-level accuracy but this
-    is a simpler method to calculate long range distances without increasing computational
-    intensity.
+    Representing the earth as an ellipsoid allows us to approximate distances between
+    points on the surface much better than a sphere. Ellipsoidal formulas treat the
+    Earth as an oblate ellipsoid which means accounting for the flattening that happens
+    at the North and South poles. Lambert's formulae provide accuracy on the order of
+    10 meteres over thousands of kilometeres. Other methods can provide
+    millimeter-level accuracy but this is a simpler method to calculate long range
+    distances without increasing computational intensity.
 
     Args:
         lat1, lon1: latitude and longitude of coordinate 1
@@ -50,7 +51,8 @@ def lamberts_ellipsoidal_distance(
     # Equation Parameters
     # https://en.wikipedia.org/wiki/Geographical_distance#Lambert's_formula_for_long_lines
     flattening = (AXIS_A - AXIS_B) / AXIS_A
-    # Parametric latitudes https://en.wikipedia.org/wiki/Latitude#Parametric_(or_reduced)_latitude
+    # Parametric latitudes
+    # https://en.wikipedia.org/wiki/Latitude#Parametric_(or_reduced)_latitude
     b_lat1 = atan((1 - flattening) * tan(radians(lat1)))
     b_lat2 = atan((1 - flattening) * tan(radians(lat2)))
 

graphs/a_star.py

@@ -53,8 +53,8 @@ def search(grid, init, goal, cost, heuristic):
     while not found and not resign:
         if len(cell) == 0:
             return "FAIL"
-        else:
-            cell.sort()  # to choose the least costliest action so as to move closer to the goal
+        else:  # to choose the least costliest action so as to move closer to the goal
+            cell.sort()
             cell.reverse()
             next = cell.pop()
             x = next[2]

graphs/graphs_floyd_warshall.py

@@ -1,7 +1,7 @@
 # floyd_warshall.py
 """
-    The problem is to find the shortest distance between all pairs of vertices in a weighted directed graph that can
-    have negative edge weights.
+    The problem is to find the shortest distance between all pairs of vertices in a
+    weighted directed graph that can have negative edge weights.
 """
 
 
@@ -26,10 +26,11 @@ def floyd_warshall(graph, v):
     distance[u][v] will contain the shortest distance from vertex u to v.
 
     1. For all edges from v to n, distance[i][j] = weight(edge(i, j)).
-    3. The algorithm then performs distance[i][j] = min(distance[i][j], distance[i][k] + distance[k][j]) for each
-    possible pair i, j of vertices.
+    3. The algorithm then performs distance[i][j] = min(distance[i][j], distance[i][k] +
+        distance[k][j]) for each possible pair i, j of vertices.
     4. The above is repeated for each vertex k in the graph.
-    5. Whenever distance[i][j] is given a new minimum value, next vertex[i][j] is updated to the next vertex[i][k].
+    5. Whenever distance[i][j] is given a new minimum value, next vertex[i][j] is
+        updated to the next vertex[i][k].
     """
 
     dist = [[float("inf") for _ in range(v)] for _ in range(v)]

graphs/minimum_spanning_tree_prims.py

@@ -72,7 +72,8 @@ def PrimsAlgorithm(l):  # noqa: E741
 
     visited = [0 for i in range(len(l))]
     Nbr_TV = [-1 for i in range(len(l))]  # Neighboring Tree Vertex of selected vertex
-    # Minimum Distance of explored vertex with neighboring vertex of partial tree formed in graph
+    # Minimum Distance of explored vertex with neighboring vertex of partial tree
+    # formed in graph
     Distance_TV = []  # Heap of Distance of vertices from their neighboring vertex
     Positions = []
 

graphs/tarjans_scc.py

@@ -5,19 +5,20 @@ def tarjan(g):
     """
     Tarjan's algo for finding strongly connected components in a directed graph
 
-    Uses two main attributes of each node to track reachability, the index of that node within a component(index),
-    and the lowest index reachable from that node(lowlink).
+    Uses two main attributes of each node to track reachability, the index of that node
+    within a component(index), and the lowest index reachable from that node(lowlink).
 
-    We then perform a dfs of the each component making sure to update these parameters for each node and saving the
-    nodes we visit on the way.
+    We then perform a dfs of the each component making sure to update these parameters
+    for each node and saving the nodes we visit on the way.
 
-    If ever we find that the lowest reachable node from a current node is equal to the index of the current node then it
-    must be the root of a strongly connected component and so we save it and it's equireachable vertices as a strongly
+    If ever we find that the lowest reachable node from a current node is equal to the
+    index of the current node then it must be the root of a strongly connected
+    component and so we save it and it's equireachable vertices as a strongly
     connected component.
 
-    Complexity: strong_connect() is called at most once for each node and has a complexity of O(|E|) as it is DFS.
+    Complexity: strong_connect() is called at most once for each node and has a
+    complexity of O(|E|) as it is DFS.
     Therefore this has complexity O(|V| + |E|) for a graph G = (V, E)
-
     """
 
     n = len(g)

hashes/adler32.py

@@ -1,7 +1,9 @@
 """
     Adler-32 is a checksum algorithm which was invented by Mark Adler in 1995.
-    Compared to a cyclic redundancy check of the same length, it trades reliability for speed (preferring the latter).
-    Adler-32 is more reliable than Fletcher-16, and slightly less reliable than Fletcher-32.[2]
+    Compared to a cyclic redundancy check of the same length, it trades reliability for
+    speed (preferring the latter).
+    Adler-32 is more reliable than Fletcher-16, and slightly less reliable than
+    Fletcher-32.[2]
 
     source: https://en.wikipedia.org/wiki/Adler-32
 """

hashes/sdbm.py

@@ -1,13 +1,17 @@
 """
-    This algorithm was created for sdbm (a public-domain reimplementation of ndbm) database library.
-    It was found to do well in scrambling bits, causing better distribution of the keys and fewer splits.
+    This algorithm was created for sdbm (a public-domain reimplementation of ndbm)
+    database library.
+    It was found to do well in scrambling bits, causing better distribution of the keys
+    and fewer splits.
     It also happens to be a good general hashing function with good distribution.
     The actual function (pseudo code) is:
         for i in i..len(str):
             hash(i) = hash(i - 1) * 65599 + str[i];
 
-    What is included below is the faster version used in gawk. [there is even a faster, duff-device version]
-    The magic constant 65599 was picked out of thin air while experimenting with different constants.
+    What is included below is the faster version used in gawk. [there is even a faster,
+    duff-device version]
+    The magic constant 65599 was picked out of thin air while experimenting with
+    different constants.
     It turns out to be a prime.
     This is one of the algorithms used in berkeley db (see sleepycat) and elsewhere.
 
@@ -18,7 +22,8 @@
 def sdbm(plain_text: str) -> str:
     """
     Function implements sdbm hash, easy to use, great for bits scrambling.
-    iterates over each character in the given string and applies function to each of them.
+    iterates over each character in the given string and applies function to each of
+    them.
 
     >>> sdbm('Algorithms')
     1462174910723540325254304520539387479031000036

hashes/sha1.py

@@ -3,7 +3,8 @@ Demonstrates implementation of SHA1 Hash function in a Python class and gives ut
 to find hash of string or hash of text from a file.
 Usage: python sha1.py --string "Hello World!!"
        python sha1.py --file "hello_world.txt"
-       When run without any arguments, it prints the hash of the string "Hello World!! Welcome to Cryptography"
+       When run without any arguments, it prints the hash of the string "Hello World!!
+       Welcome to Cryptography"
 Also contains a Test class to verify that the generated Hash is same as that
 returned by the hashlib library
 
@@ -39,7 +40,8 @@ class SHA1Hash:
     def __init__(self, data):
         """
         Inititates the variables data and h. h is a list of 5 8-digit Hexadecimal
-        numbers corresponding to (1732584193, 4023233417, 2562383102, 271733878, 3285377520)
+        numbers corresponding to
+        (1732584193, 4023233417, 2562383102, 271733878, 3285377520)
         respectively. We will start with this as a message digest. 0x is how you write
         Hexadecimal numbers in Python
         """
@@ -74,8 +76,8 @@ class SHA1Hash:
     # @staticmethod
     def expand_block(self, block):
         """
-        Takes a bytestring-block of length 64, unpacks it to a list of integers and returns a
-        list of 80 integers after some bit operations
+        Takes a bytestring-block of length 64, unpacks it to a list of integers and
+        returns a list of 80 integers after some bit operations
         """
         w = list(struct.unpack(">16L", block)) + [0] * 64
         for i in range(16, 80):
@@ -84,12 +86,13 @@ class SHA1Hash:
 
     def final_hash(self):
         """
-        Calls all the other methods to process the input. Pads the data, then splits into
-        blocks and then does a series of operations for each block (including expansion).
+        Calls all the other methods to process the input. Pads the data, then splits
+        into blocks and then does a series of operations for each block (including
+        expansion).
         For each block, the variable h that was initialized is copied to a,b,c,d,e
-        and these 5 variables a,b,c,d,e undergo several changes. After all the blocks are
-        processed, these 5 variables are pairwise added to h ie a to h[0], b to h[1] and so on.
-        This h becomes our final hash which is returned.
+        and these 5 variables a,b,c,d,e undergo several changes. After all the blocks
+        are processed, these 5 variables are pairwise added to h ie a to h[0], b to h[1]
+        and so on.  This h becomes our final hash which is returned.
         """
         self.padded_data = self.padding()
         self.blocks = self.split_blocks()
@@ -138,8 +141,8 @@ class SHA1HashTest(unittest.TestCase):
 
 def main():
     """
-    Provides option 'string' or 'file' to take input and prints the calculated SHA1 hash.
-    unittest.main() has been commented because we probably don't want to run
+    Provides option 'string' or 'file' to take input and prints the calculated SHA1
+    hash.  unittest.main() has been commented because we probably don't want to run
     the test each time.
     """
     # unittest.main()

machine_learning/gradient_descent.py

@@ -1,5 +1,6 @@
 """
-Implementation of gradient descent algorithm for minimizing cost of a linear hypothesis function.
+Implementation of gradient descent algorithm for minimizing cost of a linear hypothesis
+function.
 """
 import numpy
 
@@ -75,7 +76,8 @@ def summation_of_cost_derivative(index, end=m):
     :param index: index wrt derivative is being calculated
     :param end: value where summation ends, default is m, number of examples
     :return: Returns the summation of cost derivative
-    Note: If index is -1, this means we are calculating summation wrt to biased parameter.
+    Note: If index is -1, this means we are calculating summation wrt to biased
+        parameter.
     """
     summation_value = 0
     for i in range(end):
@@ -90,7 +92,8 @@ def get_cost_derivative(index):
     """
     :param index: index of the parameter vector wrt to derivative is to be calculated
     :return: derivative wrt to that index
-    Note: If index is -1, this means we are calculating summation wrt to biased parameter.
+    Note: If index is -1, this means we are calculating summation wrt to biased
+        parameter.
     """
     cost_derivative_value = summation_of_cost_derivative(index, m) / m
     return cost_derivative_value

machine_learning/polymonial_regression.py

@@ -10,7 +10,8 @@ from sklearn.preprocessing import PolynomialFeatures
 
 # Importing the dataset
 dataset = pd.read_csv(
-    "https://s3.us-west-2.amazonaws.com/public.gamelab.fun/dataset/position_salaries.csv"
+    "https://s3.us-west-2.amazonaws.com/public.gamelab.fun/dataset/"
+    "position_salaries.csv"
 )
 X = dataset.iloc[:, 1:2].values
 y = dataset.iloc[:, 2].values

machine_learning/sequential_minimum_optimization.py

@@ -42,7 +42,10 @@ import pandas as pd
 from sklearn.datasets import make_blobs, make_circles
 from sklearn.preprocessing import StandardScaler
 
-CANCER_DATASET_URL = "http://archive.ics.uci.edu/ml/machine-learning-databases/breast-cancer-wisconsin/wdbc.data"
+CANCER_DATASET_URL = (
+    "http://archive.ics.uci.edu/ml/machine-learning-databases/"
+    "breast-cancer-wisconsin/wdbc.data"
+)
 
 
 class SmoSVM:
@@ -124,7 +127,8 @@ class SmoSVM:
             b_old = self._b
             self._b = b
 
-            # 4:  update error value,here we only calculate those non-bound samples' error
+            # 4:  update error value,here we only calculate those non-bound samples'
+            #     error
             self._unbound = [i for i in self._all_samples if self._is_unbound(i)]
             for s in self.unbound:
                 if s == i1 or s == i2:
@@ -231,8 +235,10 @@ class SmoSVM:
         """
         Choose first alpha ;steps:
            1:First loop over all sample
-           2:Second loop over all non-bound samples till all non-bound samples does not voilate kkt condition.
-           3:Repeat this two process endlessly,till all samples does not voilate kkt condition samples after first loop.
+           2:Second loop over all non-bound samples till all non-bound samples does not
+               voilate kkt condition.
+           3:Repeat this two process endlessly,till all samples does not voilate kkt
+               condition samples after first loop.
         """
         while True:
             all_not_obey = True
@@ -352,8 +358,8 @@ class SmoSVM:
             )
             """
             # way 2
-            Use objective function check which alpha2 new could get the minimal objectives
-
+            Use objective function check which alpha2 new could get the minimal
+            objectives
             """
             if ol < (oh - self._eps):
                 a2_new = L
@@ -572,11 +578,11 @@ def plot_partition_boundary(
     model, train_data, ax, resolution=100, colors=("b", "k", "r")
 ):
     """
-    We can not get the optimum w of our kernel svm model which is different from linear svm.
-    For this reason, we generate randomly distributed points with high desity and prediced values of these points are
-    calculated by using our tained model. Then we could use this prediced values to draw contour map.
+    We can not get the optimum w of our kernel svm model which is different from linear
+    svm.  For this reason, we generate randomly distributed points with high desity and
+    prediced values of these points are calculated by using our tained model. Then we
+    could use this prediced values to draw contour map.
     And this contour map can represent svm's partition boundary.
-
     """
     train_data_x = train_data[:, 1]
     train_data_y = train_data[:, 2]

maths/bailey_borwein_plouffe.py

@@ -4,7 +4,8 @@ def bailey_borwein_plouffe(digit_position: int, precision: int = 1000) -> str:
     Bailey-Borwein-Plouffe (BBP) formula to calculate the nth hex digit of pi.
     Wikipedia page:
     https://en.wikipedia.org/wiki/Bailey%E2%80%93Borwein%E2%80%93Plouffe_formula
-    @param digit_position: a positive integer representing the position of the digit to extract.
+    @param digit_position: a positive integer representing the position of the digit to
+    extract.
     The digit immediately after the decimal point is located at position 1.
     @param precision: number of terms in the second summation to calculate.
     A higher number reduces the chance of an error but increases the runtime.
@@ -41,7 +42,8 @@ def bailey_borwein_plouffe(digit_position: int, precision: int = 1000) -> str:
     elif (not isinstance(precision, int)) or (precision < 0):
         raise ValueError("Precision must be a nonnegative integer")
 
-    # compute an approximation of (16 ** (n - 1)) * pi whose fractional part is mostly accurate
+    # compute an approximation of (16 ** (n - 1)) * pi whose fractional part is mostly
+    # accurate
     sum_result = (
         4 * _subsum(digit_position, 1, precision)
         - 2 * _subsum(digit_position, 4, precision)
@@ -70,8 +72,9 @@ def _subsum(
         denominator = 8 * sum_index + denominator_addend
         exponential_term = 0.0
         if sum_index < digit_pos_to_extract:
-            # if the exponential term is an integer and we mod it by the denominator before
-            # dividing, only the integer part of the sum will change; the fractional part will not
+            # if the exponential term is an integer and we mod it by the denominator
+            # before dividing, only the integer part of the sum will change;
+            # the fractional part will not
             exponential_term = pow(
                 16, digit_pos_to_extract - 1 - sum_index, denominator
             )

maths/ceil.py

@@ -6,7 +6,8 @@ def ceil(x) -> int:
     :return: the smallest integer >= x.
 
     >>> import math
-    >>> all(ceil(n) == math.ceil(n) for n in (1, -1, 0, -0, 1.1, -1.1, 1.0, -1.0, 1_000_000_000))
+    >>> all(ceil(n) == math.ceil(n) for n
+    ...     in (1, -1, 0, -0, 1.1, -1.1, 1.0, -1.0, 1_000_000_000))
     True
     """
     return (

maths/fermat_little_theorem.py

@@ -1,5 +1,6 @@
 # Python program to show the usage of Fermat's little theorem in a division
-# According to Fermat's little theorem, (a / b) mod p always equals a * (b ^ (p - 2)) mod p
+# According to Fermat's little theorem, (a / b) mod p always equals
+# a * (b ^ (p - 2)) mod p
 # Here we assume that p is a prime number, b divides a, and p doesn't divide b
 # Wikipedia reference: https://en.wikipedia.org/wiki/Fermat%27s_little_theorem
 

maths/fibonacci.py

@@ -4,7 +4,8 @@
 
 2. Calculates the fibonacci sequence with a formula
     an = [ Phin - (phi)n ]/Sqrt[5]
-    reference-->Su, Francis E., et al. "Fibonacci Number Formula." Math Fun Facts. <http://www.math.hmc.edu/funfacts>
+    reference-->Su, Francis E., et al. "Fibonacci Number Formula." Math Fun Facts.
+    <http://www.math.hmc.edu/funfacts>
 """
 import math
 import functools
@@ -71,11 +72,13 @@ def _check_number_input(n, min_thresh, max_thresh=None):
         print("Incorrect Input: number must not be less than 0")
     except ValueTooSmallError:
         print(
-            f"Incorrect Input: input number must be > {min_thresh} for the recursive calculation"
+            f"Incorrect Input: input number must be > {min_thresh} for the recursive "
+            "calculation"
         )
     except ValueTooLargeError:
         print(
-            f"Incorrect Input: input number must be < {max_thresh} for the recursive calculation"
+            f"Incorrect Input: input number must be < {max_thresh} for the recursive "
+            "calculation"
         )
     return False
 

maths/floor.py

@@ -6,7 +6,8 @@ def floor(x) -> int:
     :return: the largest integer <= x.
 
     >>> import math
-    >>> all(floor(n) == math.floor(n) for n in (1, -1, 0, -0, 1.1, -1.1, 1.0, -1.0, 1_000_000_000))
+    >>> all(floor(n) == math.floor(n) for n
+    ...     in (1, -1, 0, -0, 1.1, -1.1, 1.0, -1.0, 1_000_000_000))
     True
     """
     return (

maths/gamma.py

@@ -8,7 +8,8 @@ def gamma(num: float) -> float:
     https://en.wikipedia.org/wiki/Gamma_function
     In mathematics, the gamma function is one commonly
     used extension of the factorial function to complex numbers.
-    The gamma function is defined for all complex numbers except the non-positive integers
+    The gamma function is defined for all complex numbers except the non-positive
+    integers
 
 
     >>> gamma(-1)

maths/greatest_common_divisor.py

@@ -25,9 +25,9 @@ def greatest_common_divisor(a, b):
 
 
 """
-Below method is more memory efficient because it does not use the stack (chunk of memory).
-While above method is good, uses more memory for huge numbers because of the recursive calls
-required to calculate the greatest common divisor.
+Below method is more memory efficient because it does not use the stack (chunk of
+memory).  While above method is good, uses more memory for huge numbers because of the
+recursive calls required to calculate the greatest common divisor.
 """
 
 
@@ -50,7 +50,8 @@ def main():
         num_1 = int(nums[0])
         num_2 = int(nums[1])
         print(
-            f"greatest_common_divisor({num_1}, {num_2}) = {greatest_common_divisor(num_1, num_2)}"
+            f"greatest_common_divisor({num_1}, {num_2}) = "
+            f"{greatest_common_divisor(num_1, num_2)}"
         )
         print(f"By iterative gcd({num_1}, {num_2}) = {gcd_by_iterative(num_1, num_2)}")
     except (IndexError, UnboundLocalError, ValueError):

maths/lucas_lehmer_primality_test.py

@@ -1,6 +1,6 @@
 """
-        In mathematics, the Lucas–Lehmer test (LLT) is a primality test for Mersenne numbers.
-        https://en.wikipedia.org/wiki/Lucas%E2%80%93Lehmer_primality_test
+        In mathematics, the Lucas–Lehmer test (LLT) is a primality test for Mersenne
+        numbers.  https://en.wikipedia.org/wiki/Lucas%E2%80%93Lehmer_primality_test
 
         A Mersenne number is a number that is one less than a power of two.
         That is M_p = 2^p - 1

maths/matrix_exponentiation.py

@@ -15,7 +15,7 @@ class Matrix:
         if isinstance(arg, list):  # Initializes a matrix identical to the one provided.
             self.t = arg
             self.n = len(arg)
-        else:  # Initializes a square matrix of the given size and set the values to zero.
+        else:  # Initializes a square matrix of the given size and set values to zero.
             self.n = arg
             self.t = [[0 for _ in range(self.n)] for _ in range(self.n)]
 

maths/modular_exponential.py

@@ -1,7 +1,8 @@
 """
     Modular Exponential.
     Modular exponentiation is a type of exponentiation performed over a modulus.
-    For more explanation, please check https://en.wikipedia.org/wiki/Modular_exponentiation
+    For more explanation, please check
+    https://en.wikipedia.org/wiki/Modular_exponentiation
 """
 
 """Calculate Modular Exponential."""

maths/polynomial_evaluation.py

@@ -44,7 +44,8 @@ if __name__ == "__main__":
     Example:
     >>> poly = (0.0, 0.0, 5.0, 9.3, 7.0)  # f(x) = 7.0x^4 + 9.3x^3 + 5.0x^2
     >>> x = -13.0
-    >>> print(evaluate_poly(poly, x))  # f(-13) = 7.0(-13)^4 + 9.3(-13)^3 + 5.0(-13)^2 = 180339.9
+    >>> # f(-13) = 7.0(-13)^4 + 9.3(-13)^3 + 5.0(-13)^2 = 180339.9
+    >>> print(evaluate_poly(poly, x))
     180339.9
     """
     poly = (0.0, 0.0, 5.0, 9.3, 7.0)

maths/relu.py

@@ -1,7 +1,8 @@
 """
 This script demonstrates the implementation of the ReLU function.
 
-It's a kind of activation function defined as the positive part of its argument in the context of neural network.
+It's a kind of activation function defined as the positive part of its argument in the
+context of neural network.
 The function takes a vector of K real numbers as input and then argmax(x, 0).
 After through ReLU, the element of the vector always 0 or real number.
 

maths/sieve_of_eratosthenes.py

@@ -1,8 +1,10 @@
 """
 Sieve of Eratosthones
 
-The sieve of Eratosthenes is an algorithm used to find prime numbers, less than or equal to a given value.
-Illustration: https://upload.wikimedia.org/wikipedia/commons/b/b9/Sieve_of_Eratosthenes_animation.gif
+The sieve of Eratosthenes is an algorithm used to find prime numbers, less than or
+equal to a given value.
+Illustration:
+https://upload.wikimedia.org/wikipedia/commons/b/b9/Sieve_of_Eratosthenes_animation.gif
 Reference: https://en.wikipedia.org/wiki/Sieve_of_Eratosthenes
 
 doctest provider: Bruno Simas Hadlich (https://github.com/brunohadlich)

maths/square_root.py

@@ -25,7 +25,8 @@ def square_root_iterative(
     Square root is aproximated using Newtons method.
     https://en.wikipedia.org/wiki/Newton%27s_method
 
-    >>> all(abs(square_root_iterative(i)-math.sqrt(i)) <= .00000000000001  for i in range(0, 500))
+    >>> all(abs(square_root_iterative(i)-math.sqrt(i)) <= .00000000000001
+    ...     for i in range(500))
     True
 
     >>> square_root_iterative(-1)

matrix/nth_fibonacci_using_matrix_exponentiation.py

@@ -1,6 +1,7 @@
 """
 Implementation of finding nth fibonacci number using matrix exponentiation.
-Time Complexity is about O(log(n)*8), where 8 is the complexity of matrix multiplication of size 2 by 2.
+Time Complexity is about O(log(n)*8), where 8 is the complexity of matrix
+multiplication of size 2 by 2.
 And on the other hand complexity of bruteforce solution is O(n).
 As we know
     f[n] = f[n-1] + f[n-1]
@@ -70,7 +71,10 @@ def nth_fibonacci_bruteforce(n):
 
 
 def main():
-    fmt = "{} fibonacci number using matrix exponentiation is {} and using bruteforce is {}\n"
+    fmt = (
+        "{} fibonacci number using matrix exponentiation is {} and using bruteforce "
+        "is {}\n"
+    )
     for ordinal in "0th 1st 2nd 3rd 10th 100th 1000th".split():
         n = int("".join(c for c in ordinal if c in "0123456789"))  # 1000th --> 1000
         print(fmt.format(ordinal, nth_fibonacci_matrix(n), nth_fibonacci_bruteforce(n)))

matrix/rotate_matrix.py

@@ -1,5 +1,6 @@
 """
-In this problem, we want to rotate the matrix elements by 90, 180, 270 (counterclockwise)
+In this problem, we want to rotate the matrix elements by 90, 180, 270
+(counterclockwise)
 Discussion in stackoverflow:
 https://stackoverflow.com/questions/42519/how-do-you-rotate-a-two-dimensional-array
 """

matrix/sherman_morrison.py

@@ -207,8 +207,10 @@ class Matrix:
         """
         <method Matrix.ShermanMorrison>
         Apply Sherman-Morrison formula in O(n^2).
-        To learn this formula, please look this: https://en.wikipedia.org/wiki/Sherman%E2%80%93Morrison_formula
-        This method returns (A + uv^T)^(-1) where A^(-1) is self. Returns None if it's impossible to calculate.
+        To learn this formula, please look this:
+        https://en.wikipedia.org/wiki/Sherman%E2%80%93Morrison_formula
+        This method returns (A + uv^T)^(-1) where A^(-1) is self. Returns None if it's
+        impossible to calculate.
         Warning: This method doesn't check if self is invertible.
             Make sure self is invertible before execute this method.
 

matrix/tests/test_matrix_operation.py

@@ -1,7 +1,8 @@
 """
 Testing here assumes that numpy and linalg is ALWAYS correct!!!!
 
-If running from PyCharm you can place the following line in "Additional Arguments" for the pytest run configuration
+If running from PyCharm you can place the following line in "Additional Arguments" for
+the pytest run configuration
 -vv -m mat_ops -p no:cacheprovider
 """
 

other/dijkstra_bankers_algorithm.py

@@ -88,9 +88,11 @@ class BankersAlgorithm:
         This function builds an index control dictionary to track original ids/indices
         of processes when altered during execution of method "main"
             Return: {0: [a: int, b: int], 1: [c: int, d: int]}
-        >>> BankersAlgorithm(test_claim_vector, test_allocated_res_table,
+        >>> (BankersAlgorithm(test_claim_vector, test_allocated_res_table,
         ...     test_maximum_claim_table)._BankersAlgorithm__need_index_manager()
-        {0: [1, 2, 0, 3], 1: [0, 1, 3, 1], 2: [1, 1, 0, 2], 3: [1, 3, 2, 0], 4: [2, 0, 0, 3]}
+        ...     )  # doctest: +NORMALIZE_WHITESPACE
+        {0: [1, 2, 0, 3], 1: [0, 1, 3, 1], 2: [1, 1, 0, 2], 3: [1, 3, 2, 0],
+         4: [2, 0, 0, 3]}
         """
         return {self.__need().index(i): i for i in self.__need()}
 

other/fischer_yates_shuffle.py

@@ -1,6 +1,7 @@
 #!/usr/bin/python
 """
-The Fisher–Yates shuffle is an algorithm for generating a random permutation of a finite sequence.
+The Fisher–Yates shuffle is an algorithm for generating a random permutation of a
+finite sequence.
 For more details visit
 wikipedia/Fischer-Yates-Shuffle.
 """

other/game_of_life.py

@@ -52,7 +52,8 @@ def seed(canvas):
 
 
 def run(canvas):
-    """ This  function runs the rules of game through all points, and changes their status accordingly.(in the same canvas)
+    """ This  function runs the rules of game through all points, and changes their
+    status accordingly.(in the same canvas)
     @Args:
     --
     canvas : canvas of population to run the rules on.

other/integeration_by_simpson_approx.py

@@ -4,7 +4,8 @@ Github : faizan2700
 
 Purpose : You have one function f(x) which takes float integer and returns
 float you have to integrate the function in limits a to b.
-The approximation proposed by Thomas Simpsons in 1743 is one way to calculate integration.
+The approximation proposed by Thomas Simpsons in 1743 is one way to calculate
+integration.
 
 ( read article : https://cp-algorithms.com/num_methods/simpson-integration.html )
 
@@ -25,7 +26,8 @@ def f(x: float) -> float:
 Summary of Simpson Approximation :
 
 By simpsons integration :
-1.integration of fxdx with limit a to b is = f(x0) + 4 * f(x1) + 2 * f(x2) + 4 * f(x3) + 2 * f(x4)..... + f(xn)
+1. integration of fxdx with limit a to b is =
+    f(x0) + 4 * f(x1) + 2 * f(x2) + 4 * f(x3) + 2 * f(x4)..... + f(xn)
 where x0 = a
 xi = a + i * h
 xn = b
@@ -71,7 +73,7 @@ def simpson_integration(function, a: float, b: float, precision: int = 4) -> flo
     >>> simpson_integration('wrong_input',2,3,4)
     Traceback (most recent call last):
         ...
-    AssertionError: the function(object) passed should be callable your input : wrong_input
+    AssertionError: the function(object) passed should be callable your input : ...
 
     >>> simpson_integration(lambda x : x*x,3.45,3.2,1)
     -2.8
@@ -93,9 +95,10 @@ def simpson_integration(function, a: float, b: float, precision: int = 4) -> flo
     assert isinstance(a, float) or isinstance(
         a, int
     ), f"a should be float or integer your input : {a}"
-    assert isinstance(function(a), float) or isinstance(
-        function(a), int
-    ), f"the function should return integer or float return type of your function, {type(a)}"
+    assert isinstance(function(a), float) or isinstance(function(a), int), (
+        "the function should return integer or float return type of your function, "
+        f"{type(a)}"
+    )
     assert isinstance(b, float) or isinstance(
         b, int
     ), f"b should be float or integer your input : {b}"

other/linear_congruential_generator.py

@@ -23,7 +23,8 @@ class LinearCongruentialGenerator:
     def next_number(self):
         """
         The smallest number that can be generated is zero.
-        The largest number that can be generated is modulo-1. modulo is set in the constructor.
+        The largest number that can be generated is modulo-1. modulo is set in the
+        constructor.
         """
         self.seed = (self.multiplier * self.seed + self.increment) % self.modulo
         return self.seed

other/nested_brackets.py

@@ -9,9 +9,8 @@ if any of the following conditions are true:
 
 For example, the string "()()[()]" is properly nested but "[(()]" is not.
 
-The function called is_balanced takes as input a string S which is a sequence of brackets and
-returns true if S is nested and false otherwise.
-
+The function called is_balanced takes as input a string S which is a sequence of
+brackets and returns true if S is nested and false otherwise.
 """
 
 
@@ -37,14 +36,11 @@ def is_balanced(S):
 
 
 def main():
-
-    S = input("Enter sequence of brackets: ")
-
-    if is_balanced(S):
-        print((S, "is balanced"))
-
+    s = input("Enter sequence of brackets: ")
+    if is_balanced(s):
+        print(s, "is balanced")
     else:
-        print((S, "is not balanced"))
+        print(s, "is not balanced")
 
 
 if __name__ == "__main__":

other/two_sum.py

@@ -1,7 +1,9 @@
 """
-Given an array of integers, return indices of the two numbers such that they add up to a specific target.
+Given an array of integers, return indices of the two numbers such that they add up to
+a specific target.
 
-You may assume that each input would have exactly one solution, and you may not use the same element twice.
+You may assume that each input would have exactly one solution, and you may not use the
+same element twice.
 
 Example:
 Given nums = [2, 7, 11, 15], target = 9,

project_euler/problem_30/soln.py

@@ -1,6 +1,7 @@
 """ Problem Statement (Digit Fifth Power ): https://projecteuler.net/problem=30
 
-Surprisingly there are only three numbers that can be written as the sum of fourth powers of their digits:
+Surprisingly there are only three numbers that can be written as the sum of fourth
+powers of their digits:
 
 1634 = 1^4 + 6^4 + 3^4 + 4^4
 8208 = 8^4 + 2^4 + 0^4 + 8^4
@@ -9,7 +10,8 @@ As 1 = 1^4 is not a sum it is not included.
 
 The sum of these numbers is 1634 + 8208 + 9474 = 19316.
 
-Find the sum of all the numbers that can be written as the sum of fifth powers of their digits.
+Find the sum of all the numbers that can be written as the sum of fifth powers of their
+digits.
 
 (9^5)=59,049‬
 59049*7=4,13,343 (which is only 6 digit number )

project_euler/problem_56/sol1.py

@@ -15,7 +15,8 @@ def maximum_digital_sum(a: int, b: int) -> int:
         1872
     """
 
-    # RETURN the MAXIMUM from the list of SUMs of the list of INT converted from STR of BASE raised to the POWER
+    # RETURN the MAXIMUM from the list of SUMs of the list of INT converted from STR of
+    # BASE raised to the POWER
     return max(
         [
             sum([int(x) for x in str(base ** power)])

scheduling/first_come_first_served.py

@@ -101,7 +101,8 @@ if __name__ == "__main__":
     print("Process ID\tDuration Time\tWaiting Time\tTurnaround Time")
     for i, process in enumerate(processes):
         print(
-            f"{process}\t\t{duration_times[i]}\t\t{waiting_times[i]}\t\t{turnaround_times[i]}"
+            f"{process}\t\t{duration_times[i]}\t\t{waiting_times[i]}\t\t"
+            f"{turnaround_times[i]}"
         )
     print(f"Average waiting time = {average_waiting_time}")
     print(f"Average turn around time = {average_turnaround_time}")

searches/linear_search.py

@@ -14,7 +14,8 @@ python linear_search.py
 def linear_search(sequence, target):
     """Pure implementation of linear search algorithm in Python
 
-    :param sequence: a collection with comparable items (as sorted items not required in Linear Search)
+    :param sequence: a collection with comparable items (as sorted items not required
+        in Linear Search)
     :param target: item value to search
     :return: index of found item or None if item is not found
 

searches/simulated_annealing.py

@@ -18,11 +18,13 @@ def simulated_annealing(
     threshold_temp: float = 1,
 ) -> SearchProblem:
     """
-        implementation of the simulated annealing algorithm. We start with a given state, find
-            all its neighbors. Pick a random neighbor, if that neighbor improves the solution, we move
-            in that direction, if that neighbor does not improve the solution, we generate a random
-            real number between 0 and 1, if the number is within a certain range (calculated using
-            temperature) we move in that direction, else we pick another neighbor randomly and repeat the process.
+    Implementation of the simulated annealing algorithm. We start with a given state,
+    find all its neighbors. Pick a random neighbor, if that neighbor improves the
+    solution, we move in that direction, if that neighbor does not improve the solution,
+    we generate a random real number between 0 and 1, if the number is within a certain
+    range (calculated using temperature) we move in that direction, else we pick
+    another neighbor randomly and repeat the process.
+
     Args:
         search_prob: The search state at the start.
         find_max: If True, the algorithm should find the minimum else the minimum.

searches/tabu_search.py

@@ -1,8 +1,9 @@
 """
-This is pure Python implementation of Tabu search algorithm for a Travelling Salesman Problem, that the distances
-between the cities are symmetric (the distance between city 'a' and city 'b' is the same between city 'b' and city 'a').
-The TSP can be represented into a graph. The cities are represented by nodes and the distance between them is
-represented by the weight of the ark between the nodes.
+This is pure Python implementation of Tabu search algorithm for a Travelling Salesman
+Problem, that the distances between the cities are symmetric (the distance between city
+'a' and city 'b' is the same between city 'b' and city 'a').
+The TSP can be represented into a graph. The cities are represented by nodes and the
+distance between them is represented by the weight of the ark between the nodes.
 
 The .txt file with the graph has the form:
 
@@ -10,8 +11,8 @@ node1 node2 distance_between_node1_and_node2
 node1 node3 distance_between_node1_and_node3
 ...
 
-Be careful node1, node2 and the distance between them, must exist only once. This means in the .txt file
-should not exist:
+Be careful node1, node2 and the distance between them, must exist only once. This means
+in the .txt file should not exist:
 node1 node2 distance_between_node1_and_node2
 node2 node1 distance_between_node2_and_node1
 
@@ -19,7 +20,8 @@ For pytests run following command:
 pytest
 
 For manual testing run:
-python tabu_search.py -f your_file_name.txt -number_of_iterations_of_tabu_search -s size_of_tabu_search
+python tabu_search.py -f your_file_name.txt -number_of_iterations_of_tabu_search \
+    -s size_of_tabu_search
 e.g. python tabu_search.py -f tabudata2.txt -i 4 -s 3
 """
 
@@ -33,16 +35,16 @@ def generate_neighbours(path):
     neighbor, given a path file that includes a graph.
 
     :param path: The path to the .txt file that includes the graph (e.g.tabudata2.txt)
-    :return dict_of_neighbours: Dictionary with key each node and value a list of lists with the neighbors of the node
-    and the cost (distance) for each neighbor.
+    :return dict_of_neighbours: Dictionary with key each node and value a list of lists
+        with the neighbors of the node and the cost (distance) for each neighbor.
 
     Example of dict_of_neighbours:
     >>) dict_of_neighbours[a]
     [[b,20],[c,18],[d,22],[e,26]]
 
-    This indicates the neighbors of node (city) 'a', which has neighbor the node 'b' with distance 20,
-    the node 'c' with distance 18, the node 'd' with distance 22 and the node 'e' with distance 26.
-
+    This indicates the neighbors of node (city) 'a', which has neighbor the node 'b'
+    with distance 20, the node 'c' with distance 18, the node 'd' with distance 22 and
+    the node 'e' with distance 26.
     """
 
     dict_of_neighbours = {}
@@ -71,19 +73,19 @@ def generate_neighbours(path):
 
 def generate_first_solution(path, dict_of_neighbours):
     """
-    Pure implementation of generating the first solution for the Tabu search to start, with the redundant resolution
-    strategy. That means that we start from the starting node (e.g. node 'a'), then we go to the city nearest (lowest
-    distance) to this node (let's assume is node 'c'), then we go to the nearest city of the node 'c', etc
+    Pure implementation of generating the first solution for the Tabu search to start,
+    with the redundant resolution strategy. That means that we start from the starting
+    node (e.g. node 'a'), then we go to the city nearest (lowest distance) to this node
+    (let's assume is node 'c'), then we go to the nearest city of the node 'c', etc.
     till we have visited all cities and return to the starting node.
 
     :param path: The path to the .txt file that includes the graph (e.g.tabudata2.txt)
-    :param dict_of_neighbours: Dictionary with key each node and value a list of lists with the neighbors of the node
-    and the cost (distance) for each neighbor.
-    :return first_solution: The solution for the first iteration of Tabu search using the redundant resolution strategy
-    in a list.
-    :return distance_of_first_solution: The total distance that Travelling Salesman will travel, if he follows the path
-    in first_solution.
-
+    :param dict_of_neighbours: Dictionary with key each node and value a list of lists
+        with the neighbors of the node and the cost (distance) for each neighbor.
+    :return first_solution: The solution for the first iteration of Tabu search using
+        the redundant resolution strategy in a list.
+    :return distance_of_first_solution: The total distance that Travelling Salesman
+        will travel, if he follows the path in first_solution.
     """
 
     with open(path) as f:
@@ -124,22 +126,23 @@ def generate_first_solution(path, dict_of_neighbours):
 
 def find_neighborhood(solution, dict_of_neighbours):
     """
-    Pure implementation of generating the neighborhood (sorted by total distance of each solution from
-    lowest to highest) of a solution with 1-1 exchange method, that means we exchange each node in a solution with each
-    other node and generating a number of solution named neighborhood.
+    Pure implementation of generating the neighborhood (sorted by total distance of
+    each solution from lowest to highest) of a solution with 1-1 exchange method, that
+    means we exchange each node in a solution with each other node and generating a
+    number of solution named neighborhood.
 
     :param solution: The solution in which we want to find the neighborhood.
-    :param dict_of_neighbours: Dictionary with key each node and value a list of lists with the neighbors of the node
-    and the cost (distance) for each neighbor.
-    :return neighborhood_of_solution: A list that includes the solutions and the total distance of each solution
-    (in form of list) that are produced with 1-1 exchange from the solution that the method took as an input
-
+    :param dict_of_neighbours: Dictionary with key each node and value a list of lists
+        with the neighbors of the node and the cost (distance) for each neighbor.
+    :return neighborhood_of_solution: A list that includes the solutions and the total
+        distance of each solution (in form of list) that are produced with 1-1 exchange
+        from the solution that the method took as an input
 
     Example:
-    >>) find_neighborhood(['a','c','b','d','e','a'])
-    [['a','e','b','d','c','a',90], [['a','c','d','b','e','a',90],['a','d','b','c','e','a',93],
-    ['a','c','b','e','d','a',102], ['a','c','e','d','b','a',113], ['a','b','c','d','e','a',93]]
-
+    >>> find_neighborhood(['a','c','b','d','e','a'])  # doctest: +NORMALIZE_WHITESPACE
+    [['a','e','b','d','c','a',90], [['a','c','d','b','e','a',90],
+     ['a','d','b','c','e','a',93], ['a','c','b','e','d','a',102],
+     ['a','c','e','d','b','a',113], ['a','b','c','d','e','a',93]]
     """
 
     neighborhood_of_solution = []
@@ -177,20 +180,21 @@ def tabu_search(
     first_solution, distance_of_first_solution, dict_of_neighbours, iters, size
 ):
     """
-    Pure implementation of Tabu search algorithm for a Travelling Salesman Problem in Python.
+    Pure implementation of Tabu search algorithm for a Travelling Salesman Problem in
+    Python.
 
-    :param first_solution: The solution for the first iteration of Tabu search using the redundant resolution strategy
-    in a list.
-    :param distance_of_first_solution: The total distance that Travelling Salesman will travel, if he follows the path
-    in first_solution.
-    :param dict_of_neighbours: Dictionary with key each node and value a list of lists with the neighbors of the node
-    and the cost (distance) for each neighbor.
+    :param first_solution: The solution for the first iteration of Tabu search using
+        the redundant resolution strategy in a list.
+    :param distance_of_first_solution: The total distance that Travelling Salesman will
+        travel, if he follows the path in first_solution.
+    :param dict_of_neighbours: Dictionary with key each node and value a list of lists
+        with the neighbors of the node and the cost (distance) for each neighbor.
     :param iters: The number of iterations that Tabu search will execute.
     :param size: The size of Tabu List.
-    :return best_solution_ever: The solution with the lowest distance that occurred during the execution of Tabu search.
-    :return best_cost: The total distance that Travelling Salesman will travel, if he follows the path in best_solution
-    ever.
-
+    :return best_solution_ever: The solution with the lowest distance that occurred
+        during the execution of Tabu search.
+    :return best_cost: The total distance that Travelling Salesman will travel, if he
+        follows the path in best_solution ever.
     """
     count = 1
     solution = first_solution

sorts/bucket_sort.py

@@ -17,8 +17,9 @@
 # number of buckets.
 
 #  Time Complexity of Solution:
-#  Worst case scenario occurs when all the elements are placed in a single bucket. The overall performance
-#  would then be dominated by the algorithm used to sort each bucket. In this case, O(n log n), because of TimSort
+#  Worst case scenario occurs when all the elements are placed in a single bucket. The
+# overall performance would then be dominated by the algorithm used to sort each bucket.
+# In this case, O(n log n), because of TimSort
 #
 #  Average Case O(n + (n^2)/k + k), where k is the number of buckets
 #

sorts/comb_sort.py

@@ -1,9 +1,11 @@
 """
 This is pure Python implementation of comb sort algorithm.
-Comb sort is a relatively simple sorting algorithm originally designed by Wlodzimierz Dobosiewicz in 1980.
-It was rediscovered by Stephen Lacey and Richard Box in 1991. Comb sort improves on bubble sort algorithm.
+Comb sort is a relatively simple sorting algorithm originally designed by Wlodzimierz
+Dobosiewicz in 1980.  It was rediscovered by Stephen Lacey and Richard Box in 1991.
+Comb sort improves on bubble sort algorithm.
 In bubble sort, distance (or gap) between two compared elements is always one.
-Comb sort improvement is that gap can be much more than 1, in order to prevent slowing down by small values
+Comb sort improvement is that gap can be much more than 1, in order to prevent slowing
+down by small values
 at the end of a list.
 
 More info on: https://en.wikipedia.org/wiki/Comb_sort

sorts/random_normal_distribution_quicksort.py

@@ -57,6 +57,7 @@ r = len(M) - 1
 z = _inPlaceQuickSort(M, 0, r)
 
 print(
-    "No of Comparisons for 100 elements selected from a standard normal distribution is :"
+    "No of Comparisons for 100 elements selected from a standard normal distribution"
+    "is :"
 )
 print(z)

sorts/unknown_sort.py

@@ -1,7 +1,8 @@
 """
 Python implementation of a sort algorithm.
 Best Case Scenario : O(n)
-Worst Case Scenario : O(n^2) because native Python functions:min, max and remove are already O(n)
+Worst Case Scenario : O(n^2) because native Python functions:min, max and remove are
+already O(n)
 """
 
 

strings/boyer_moore_search.py

@@ -41,7 +41,9 @@ class BoyerMooreSearch:
         return -1
 
     def mismatch_in_text(self, currentPos):
-        """ finds the index of mis-matched character in text when compared with pattern from last
+        """
+        find the index of mis-matched character in text when compared with pattern
+        from last
 
         Parameters :
             currentPos (int): current index position of text

strings/is_palindrome.py

@@ -14,8 +14,8 @@ def is_palindrome(s: str) -> bool:
     >>> is_palindrome("Mr. Owl ate my metal worm?")
     True
     """
-    # Since Punctuation, capitalization, and spaces are usually ignored while checking Palindrome,
-    # we first remove them from our string.
+    # Since Punctuation, capitalization, and spaces are usually ignored while checking
+    # Palindrome,  we first remove them from our string.
     s = "".join([character for character in s.lower() if character.isalnum()])
     return s == s[::-1]
 

strings/jaro_winkler.py

@@ -3,7 +3,8 @@
 
 def jaro_winkler(str1: str, str2: str) -> float:
     """
-    Jaro–Winkler distance is a string metric measuring an edit distance between two sequences.
+    Jaro–Winkler distance is a string metric measuring an edit distance between two
+    sequences.
     Output value is between 0.0 and 1.0.
 
     >>> jaro_winkler("martha", "marhta")

strings/knuth_morris_pratt.py

@@ -5,11 +5,11 @@ def kmp(pattern, text):
 
     1) Preprocess pattern to identify any suffixes that are identical to prefixes
 
-        This tells us where to continue from if we get a mismatch between a character in our pattern
-        and the text.
+        This tells us where to continue from if we get a mismatch between a character
+        in our pattern and the text.
 
-    2) Step through the text one character at a time and compare it to a character in the pattern
-        updating our location within the pattern if necessary
+    2) Step through the text one character at a time and compare it to a character in
+        the pattern updating our location within the pattern if necessary
 
     """
 

strings/lower.py

@@ -16,8 +16,9 @@ def lower(word: str) -> str:
     'what'
     """
 
-    # converting to ascii value int value and checking to see if char is a capital letter
-    # if it is a capital letter it is getting shift by 32 which makes it a lower case letter
+    # converting to ascii value int value and checking to see if char is a capital
+    # letter if it is a capital letter it is getting shift by 32 which makes it a lower
+    # case letter
     return "".join(
         chr(ord(char) + 32) if 65 <= ord(char) <= 90 else char for char in word
     )

strings/min_cost_string_conversion.py

@@ -1,5 +1,6 @@
 """
-Algorithm for calculating the most cost-efficient sequence for converting one string into another.
+Algorithm for calculating the most cost-efficient sequence for converting one string
+into another.
 The only allowed operations are
 ---Copy character with cost cC
 ---Replace character with cost cR

strings/rabin_karp.py

@@ -8,15 +8,18 @@ def rabin_karp(pattern, text):
     """
     The Rabin-Karp Algorithm for finding a pattern within a piece of text
     with complexity O(nm), most efficient when it is used with multiple patterns
-    as it is able to check if any of a set of patterns match a section of text in o(1) given the precomputed hashes.
+    as it is able to check if any of a set of patterns match a section of text in o(1)
+    given the precomputed hashes.
 
-    This will be the simple version which only assumes one pattern is being searched for but it's not hard to modify
+    This will be the simple version which only assumes one pattern is being searched
+    for but it's not hard to modify
 
     1) Calculate pattern hash
 
-    2) Step through the text one character at a time passing a window with the same length as the pattern
-        calculating the hash of the text within the window compare it with the hash of the pattern. Only testing
-        equality if the hashes match
+    2) Step through the text one character at a time passing a window with the same
+        length as the pattern
+        calculating the hash of the text within the window compare it with the hash
+        of the pattern. Only testing equality if the hashes match
     """
     p_len = len(pattern)
     t_len = len(text)

strings/split.py

@@ -1,6 +1,7 @@
 def split(string: str, separator: str = " ") -> list:
     """
-    Will split the string up into all the values separated by the separator (defaults to spaces)
+    Will split the string up into all the values separated by the separator
+    (defaults to spaces)
 
     >>> split("apple#banana#cherry#orange",separator='#')
     ['apple', 'banana', 'cherry', 'orange']

strings/upper.py

@@ -14,7 +14,8 @@ def upper(word: str) -> str:
     """
 
     # converting to ascii value int value and checking to see if char is a lower letter
-    # if it is a capital letter it is getting shift by 32 which makes it a capital case letter
+    # if it is a capital letter it is getting shift by 32 which makes it a capital case
+    # letter
     return "".join(
         chr(ord(char) - 32) if 97 <= ord(char) <= 122 else char for char in word
     )