When it is required to restrict elements frequency in a list, a simple iteration is used along with the ‘append’ method.ExampleBelow is a demonstration of the same −from collections import defaultdict my_list = [11, 14, 15, 14, 11, 14, 14, 15, 15, 16] print("The list is :") print(my_list) my_dict = {14 : 3, 11 : 1, 16 : 1, 15 : 2} print("The dictionary is :") print(my_dict) my_result = [] my_def_dict = defaultdict(int) for element in my_list: my_def_dict[element] += 1 if my_def_dict[element] > my_dict[element]: ... Read More

When it is required to list elements grouping in a matrix, a simple iteration, the ‘pop’ method, list comprehension and ‘append’ methods are used.ExampleBelow is a demonstration of the same −my_list = [[14, 62], [51, 23], [12, 62], [78, 87], [41, 14]] print("The list is :") print(my_list) check_list = [14, 12, 41, 62] print("The list is :") print(check_list) my_result = [] while my_list: sub_list_1 = my_list.pop() sub_list_2 = [element for element in check_list if element not in sub_list_1] try: ... Read More

When it is required to convert tuple into list by adding the given string after every element, the list comprehension is used.ExampleBelow is a demonstration of the same −my_tuple = ((15, 16), (71), 42, 99) print("The tuple is :") print(my_tuple) K = "Pyt" print("The value of K is :") print(K) my_result = [element for sub in my_tuple for element in (sub, K)] print("The result is :") print(my_result)OutputThe tuple is : ((15, 16), 71, 42, 99) The value of K is : Pyt The result is : [(15, 16), 'Pyt', 71, 'Pyt', 42, 'Pyt', 99, 'Pyt']ExplanationA tuple ... Read More

When it is required to cross join every ‘K’th element, a method is defined that uses iteration and fetches the index as output.ExampleBelow is a demonstration of the same −def merge_pair_elem(my_list_1, my_list_2, K): index_1 = 0 index_2 = 0 while(index_1 < len(my_list_1)): for i in range(K): yield my_list_1[index_1] index_1 += 1 for i in range(K): ... Read More

When it is required to find the character position of ‘K’th word from a list of strings, a list comprehension along with enumerate is used.ExampleBelow is a demonstration of the same −my_list = ["python", "is", "fun", "to", "learn"] print("The list is :") print(my_list) K = 15 print("The value of K is :") print(K) my_result = [element[0] for sub in enumerate(my_list) for element in enumerate(sub[1])] my_result = my_result[K] print("The result is :") print(my_result)OutputThe list is : ['python', 'is', 'fun', 'to', 'learn'] The value of K is : 15 The result is : 2ExplanationA list of strings ... Read More

When it is required to replace all characters of a list except a given character, a list comprehension, and the ‘==’ operator are used.ExampleBelow is a demonstration of the same −my_list = ['P', 'Y', 'T', 'H', 'O', 'N', 'P', 'H', 'P'] print("The list is :") print(my_list) replace_char = '$' retain_char = 'P' my_result = [element if element == retain_char else replace_char for element in my_list] print("The result is :") print(my_result)OutputThe list is : ['P', 'Y', 'T', 'H', 'O', 'N', 'P', 'H', 'P'] The result is : ['P', '$', '$', '$', '$', '$', 'P', '$', 'P']ExplanationA ... Read More

When it is required to concatenate strings around ‘K’, a simple iteration and the ‘append’ method is used.ExampleBelow is a demonstration of the same −my_list = ["python", "+", 'is', 'fun', "+", 'to', 'learn'] print("The list is :") print(my_list) K = "+" print("The value of K is :") print(K) my_result = [] index = 0 while index < len(my_list): element = my_list[index] if (index < len(my_list) - 1) and my_list[index + 1] == K: element = element + K + my_list[index + 2] ... Read More

When it is required to sum the consecutive numbers with overlapping elements in lists, a list comprehension, list slicing, concatenation operator and ‘zip’ methods are used.ExampleBelow is a demonstration of the same −my_list = [41, 27, 53, 12, 29, 32, 16] print("The list is :") print(my_list) my_result = [a + b for a, b in zip(my_list, my_list[1:] + [my_list[0]])] print("The result is :") print(my_result)OutputThe list is : [41, 27, 53, 12, 29, 32, 16] The result is : [68, 80, 65, 41, 61, 48, 57]ExplanationA list of integers is defined and is displayed on the console.A list ... Read More

When it is required to get the indices of each element of one list in another list, a simple iteration and the enumerate attribute along with the ‘setdefault’ method is used.It also uses list comprehension and the ‘get’ method is used.ExampleBelow is a demonstration of the same −my_list = [14, 52, 23, 47, 18, 23, 12, 54, 43, 22, 28, 13] print("The list is :") print(my_list) my_list_2 = [17, 52, 13] print("The second list is :") print(my_list_2) element_indices = dict() for index, value in enumerate(my_list): element_indices.setdefault(value, []).append(index) my_result = [element_indices.get(index, [None]) for index ... Read More

When it is required to remove rows with duplicate element in a matrix, a list comprehension and the ‘set’ operator is used.ExampleBelow is a demonstration of the same −my_list = [[34, 23, 34], [17, 46, 47], [22, 14, 22], [28, 91, 19]] print("The list is :") print(my_list) my_result = [element for element in my_list if len(set(element)) == len(element)] print("The result is :") print(my_result)OutputThe list is : [[34, 23, 34], [17, 46, 47], [22, 14, 22], [28, 91, 19]] The result is : [[17, 46, 47], [28, 91, 19]]ExplanationA list of list is defined and is displayed on ... Read More