Python Articles - Page 522 of 829

When it is required to form a dictionary with the help of an object and class, a class is defined. An ‘init’ function is defined, that assigns values to variables. An instance of the class is created, and the init function is called.ExampleBelow is a demonstration for the same − Live Democlass base_class(object):    def __init__(self):       self.A = 32       self.B = 60 my_instance = base_class() print("An instance of the class has been created") print(my_instance.__dict__)OutputAn instance of the class has been created {'A': 32, 'B': 60}ExplanationA ‘base_class’ is defined, and an object is passed to it.An ... Read More

When it is required to multiply all the elements in a dictionary, the key values in the dictionary are iterated over. The key is multiplied with the previous key, and output is determined.The dictionary is a set of key-value pairs.ExampleBelow is a demonstration for the same − Live Demomy_dict = {'Jane':99, 'Will':54, 'Mark':-3} my_result = 2 for key in my_dict:    my_result = my_result * my_dict[key] print("The reuslt of multiplying keys in a dictionary is : ") print(my_result)OutputThe reuslt of multiplying keys in a dictionary is : -32076ExplanationA dictionary is defined.A variable is assigned a certain value.The ‘key’ in the dictionary ... Read More

When it is required to generate a dictionary that contains numbers within a given range in a specific form, the input is taken from the user, and a simple ‘for’ loop is used.ExampleBelow is a demonstration for the same − Live Demomy_num = int(input("Enter a number.. ")) my_dict = dict() for elem in range(1, my_num+1):    my_dict[elem] = elem*elem print("The generated elements of the dictionary are : ") print(my_dict)OutputEnter a number.. 7 The generated elements of the dictionary are : {1: 1, 2: 4, 3: 9, 4: 16, 5: 25, 6: 36, 7: 49}ExplanationThe number is taken as user input.An ... Read More

When it is required to concatenate two dictionaries into a single entity, the ‘update’ method can be used.A dictionary is a ‘key-value’ pair.Below is a demonstration for the same −Example Live Demomy_dict_1 = {'J':12, 'W':22} my_dict_2 = {'M':67} print("The first dictionary is :") print(my_dict_1) print("The second dictionary is :") print(my_dict_2) my_dict_1.update(my_dict_2) print("The concatenated dictionary is :") print(my_dict_1)OutputThe first dictionary is : {'J': 12, 'W': 22} The second dictionary is : {'M': 67} The concatenated dictionary is : {'J': 12, 'W': 22, 'M': 67}ExplanationTwo dictionaries are defined, and are displayed on the console. The ‘update’ method is called on the first dictionary by ... Read More

When it is required to find the factorial of a number without using recursion, the ‘while’ loop can be used.ExampleBelow is a demonstration for the same − Live Demomy_num = int(input("Enter a number :")) my_factorial = 1 while(my_num>0):    my_factorial = my_factorial*my_num    my_num=my_num-1 print("The factorial of the number is : ") print(my_factorial)OutputEnter a number :7 The factorial of the number is : 5040ExplanationThe input number is takne from the user.A variable is assigned to 1.It is checked to see for being 0.If not, it is multiplied by the previous value in the variable.It is assigned to the same variable.This is ... Read More

When it is required to find the Fibonacci series without using recursion technique, the input is taken from the user, and a ‘while’ loop is used to get the numbers in the sequence.ExampleBelow is a demonstration for the same − Live Demofirst_num = int(input("Enter the first number of the fibonacci series... ")) second_num = int(input("Enter the second number of the fibonacci series... ")) num_of_terms = int(input("Enter the number of terms... ")) print(first_num, second_num) print("The numbers in fibonacci series are : ") while(num_of_terms-2):    third_num = first_num + second_num    first_num=second_num    second_num=third_num    print(third_num)    num_of_terms=num_of_terms-1OutputEnter the first number of the ... Read More

When it is required to find the length of a list with the help of recursion technique, a user defined method is used, and simple indexing technique is used.A list can be used to store heterogeneous values (i.e data of any data type like integer, floating point, strings, and so on).The recursion computes output of small bits of the bigger problem, and combines these bits to give the solution to the bigger problem.ExampleBelow is a demonstration for the same − Live Demodef list_length(my_list):    if not my_list:       return 0    return 1 + list_length(my_list[1::2]) + list_length(my_list[2::2]) my_list = ... Read More

When it is required to find the total sum of a nest list using the recursion technique, a user defined method is used, that takes the list as a parameter.The recursion computes output of small bits of the bigger problem, and combines these bits to give the solution to the bigger problem.A list can be used to store heterogeneous values (i.e data of any data type like integer, floating point, strings, and so on).ExampleBelow is a demonstration for the same − Live Demodef recursion_sum(my_list):    my_total = 0    for elem in my_list:       if (type(elem) == type([])):   ... Read More

When it is required to reverse a string using recursion technique, a user defined method is used along with recursion.The recursion computes output of small bits of the bigger problem, and combines these bits to give the solution to the bigger problem.ExampleBelow is a demonstration for the same − Live Demodef reverse_string(my_string):    if len(my_string) == 0:       return my_string    else:       return reverse_string(my_string[1:]) + my_string[0] my_str = str(input("Enter the string that needs to be reversed : ")) print("The string is :") print(my_str) print("The reversed string is :") print(reverse_string(my_str))OutputEnter the string that needs to be reversed ... Read More

When it is required to check if a string is a palindrome or not using recursion technique, simple indexing and a user defined function, along with recutsion is used.Palindromes are those strings or values which when read from left to right and right to left have the same characters in their respective indices.The recursion computes output of small bits of the bigger problem, and combines these bits to give the solution to the bigger problem.Below is a demonstration for the same −Example Live Demodef check_palindrome(my_str):    if len(my_str) < 1:       return True    else:       if ... Read More