Here are the top python lambda function examples for your project and interviews. "Python's lambda functions are a powerful way to create small, anonymous functions on the fly. In this post, we'll explore some examples of how to use lambda functions in Python. 5 Best Python Lambda Function Examples #1 Sorting a List of Tuples by the Second Element This lambda function sorts a list of tuples based on the second element of each tuple. python code my_list = [(1, 2), (4, 1), (9, 10), (13, 6), (5, 7)] sorted_list = sorted(my_list, key=lambda x: x[1]) print(sorted_list) Output: [(4, 1), (1, 2), (13, 6), (5, 7), (9, 10)] ** Process exited - Return Code: 0 ** Press Enter to exit terminal #2 Finding the Maximum Value in a List of Dictionaries This lambda function finds the maximum value in a list of dictionaries based on a specific key. python code my_list = [{'name': 'Alice', 'age': 25}, {'name': 'Bob', 'age': 30}, {'name': ...

Here is the easy way to fix the issue of the Python UnboundLocalError, allowing users to resolve any problems quickly. Python UnboundLocalError While the variable in the function has already been defined, during execution, the result prints with an error of UnboundLocalError. Below, you will find an example that explains the issue and resolution. Error: file 'example.txt' not found Traceback (most recent call last): File "main.py", line 16, in <module> open_file("example.txt") File "main.py", line 11, in open_file if f: UnboundLocalError: local variable 'f' referenced before assignment ** Process exited - Return Code: 1 ** Press Enter to exit terminal Python program using try, except and finally Below program explains how to use try, except and finally blocks in python. But during the execution, it prints UnboundLocalError. Program using try, except and finally # Define a function that may raise an exception def open_file(filename):  ...

Here's a python model script to scrape a website using the BeautifulSoup. Python script The logic below uses BeautifulSoup Package for web scraping. import requests from bs4 import BeautifulSoup url = "https://www.example.com" response = requests.get(url) soup = BeautifulSoup(response.text, "html.parser") # Print the title of the webpage print(soup.title.text) # Print all the links in the webpage for link in soup.find_all("a"):     print(link.get("href")) In this script, we first import the Requests and Beautiful Soup libraries. We then define the URL we want to scrape and use the Requests library to send a GET request to that URL. We then pass the response text to Beautiful Soup to parse the HTML contents of the webpage. We then use Beautiful Soup to extract the title of the webpage and print it to the console. We also use a for loop to find all the links in the webpage and print their href attributes to the console. This is just a basic exa...

Set is a built-in data type in Python. Furthermore, it is an unordered collection without duplicate items. Here are the two methods that explain to delete an item from a Set. Methods to delete an item from a Set discard remove Discrd Vs. Remove discard() will not raise an error if the item to remove does not exist. The remove() will raise an error if the item does not exist. Explanation to discard and remove methods Python program: #Prints all the Set items food = {"pasta", "burger", "hot dog", "pizza"} print(food) # Prints the Set items without pasta food.discard("pasta") print(food) # Prints the Set items without burger and pasta food.remove("burger") print(food) # The next two lines try to remove an item that isn't in the set! food.discard("pasta")  # this will not report an error food.remove("pasta")   # this will report an error The output: {'pasta', 'burger', 'pizza', '...

Use for-loop to read dictionary data in python. Here's an example of reading dictionary data. It's helpful to use in real projects. Python program to read dictionary data yearly_revenue = {    2017 : 1000000,    2018 : 1200000,    2019 : 1250000,    2020 : 1100000,    2021 : 1300000,  } total_income = 0 for year_id in yearly_revenue.keys() :   total_income+=yearly_revenue[year_id]   print(year_id, yearly_revenue[year_id]) print(total_income) print(total_income/len(yearly_revenue)) Output 2017 1000000 2018 1200000 2019 1250000 2020 1100000 2021 1300000 5850000 1170000.0 ** Process exited - Return Code: 0 ** Press Enter to exit the terminal Explanation The input is dictionary data. The total revenue sums up for each year. Notably, the critical point is using the dictionary keys method. References Python in-depth and sample programs

While developing python programs, you might see exception messages from python. Here's an explanation to understand each part of the message. Here're tips on how to understand python exceptions. You can find two kinds of exceptions. These are StandardError and StopIteration errors. Here is a chart that shows the types of python errors. Python exceptions class Python exceptions are basically three parts. Reading an error message produced by  Python is not very difficult . The error type, the error description, and the traceback. Understand the python exception message The Error Type There are so many in-built exception types in python. Here is the command to get all the exception types: [x for x in dir(__builtins__) if 'Error' in x] The Error description The text message right after the error type gives us a description of what exactly the problem was. These descriptions are sometimes very accurate, sometimes not. Sample error Traceback (most recent call last):     ...

Tuple in python is one of the streaming datasets. The other streaming datasets are List and Dictionary. Operations that you can perform on it are shown here for your reference. Writing tuple is easy. It has values of comma separated, and enclosed with parenthesis '()'. The values in the tuple are immutable, which means you cannot replace with new values. #1. How to create a tuple Code: Tuple example my_tuple=(1,2,3,4,5) print(my_tuple) Output: (1, 2, 3, 4, 5) ** Process exited - Return Code: 0 ** Press Enter to exit terminal #2. How to read tuple values Code: print(my_tuple[0]) Output: 1 ** Process exited - Return Code: 0 ** Press Enter to exit terminal #3. How to add two tuples Code: a=(1,6,7,8) c=(3,4,5,6,7,8) d=print(a+c) Output: (1, 6, 7, 8, 3, 4, 5, 6, 7, 8) ** Process exited - Return Code: 0 ** Press Enter to exit terminal #4.  How to count tuple values Here the count is not counting values; count the repetition of a given value. Code: sample=(1, 6, 7, 8, 3, 4, 5, 6, 7, 8...

Relational operators in Python are helpful, If you are working with numeric values to compare them. Here we explore eight different relational operators and provide examples of how each one works. So to compare numeric values it is a useful guide to refresh. Python Relational Operators Here's a frequently used list of relational operators, and these you can use to compare numeric values. The list shows how to use each operator helpful for data analysis . < <= > >= == != Is is not Python program: How to use relational operators Assign 23 to a and 11 to b. Then, apply all the comparison operators. The output is self-explanatory. Bookmark this article to refresh when you are in doubt. Example a = 23 b = 11 print("Is a greater than b?", a > b) #greater than print("Is a less than b?", a < b) #less than print("Is a greater or equal to b?", a >= b) #greater or equal print("Is a less or equal to b?", a <= b) #less or equal pr...

JavaScript object notion is also called JSON file, it's data you can write to a CSV file. Here's a sample python logic for your ready reference.  You can write a simple python program by importing the JSON, and CSV packages. This is your first step. It is helpful to use all the JSON methods in your python logic. That means the required package is JSON. So far, so good. In the next step, I'll show you how to write a Python program. You'll also find each term explained. What is JSON File JSON is key value pair file. The popular use of JSON file is to transmit data between heterogeneous applications. Python supports JSON file. What is CSV File The CSV is comma separated file. It is popularly used to send and receive data. How to Write JSON file data to a CSV file Here the JSON data that has written to CSV file. It's simple method and you can use for CSV file conversion use. import csv, json json_string = '[{"value1": 1, "value2": 2,"value3...

Here are the differences between List and NumPy Array. Both store data, but technically these are not the same. You'll find here where they differ from each other. Python Lists Here is all about Python lists: Lists can have data of different data types. For instance, data = [3, 3.2, 4.6, 6, 6.8, 9, “hello”, ‘a’] Operations such as subtraction, multiplying, and division allow doing through loops Storage space required is more, as each element is considered an object in Python Execution time is high for large datasets Lists are inbuilt data types How to create array types in Python NumPy Arrays Here is all about NumPy Arrays: Numpy arrays are containers for storing only homogeneous data types. For example: data= [3.2, 4.6, 6.8]; data=[3, 6, 9]; data=[‘hello’, ‘a’] Numpy is designed to do all mathematical operations in parallel and is also simpler than Python Numpy storage space is very much less compared to the list due to the practice of homogeneous data type Execution time is ...

Python supports various array types. Here is a list of arrays and how to create examples for your reference.  What is an array? A  Python array  is a class that mimics the array type of other languages and offers efficiency in storage, exchanging that for flexibility. How to create an array Here is the syntax to create an array: data = array('f', [12.8, 5.4, 8.0, 8.0, 9.21, 3.14]) It creates an array of 6 floating point numbers; the type is indicated by the 'f' as the first parameter to the constructor. This concept is unlike the Python norm of types being dynamic and malleable. An array is an array of one kind of thing, and an array can only hold a restricted set of types. Types of arrays Here is a list of arrays: 'b' A C++ char type 'B' A C++ unsigned char type 'i': A C++ int type 'l': A C++ long type 'f': A C++ float type 'd': A C++ double type What is an array type? Arrays are class objects and are provided in the buil...

Here is an example for  splitting a string in Python . The functions you need are strip and split to split string, or text.  Here's the string taken for split My task is I want to split address string. Historically, the address is lengthy. It contains the door number, floor number, street number, and street name. Rama Krishna 20/3 ABC street EFG Nagar US 234567 How to Split a string The python split string works in two steps. The first step is to use  strip function , which removes both leading and trailing spaces. Next, use the the split function, which splits the input string, or text into a list. Python program user_address = input("Enter an address") if user_address. strip() : #check that string is not empty (after removing leading #and trailing spaces)     print("Your address is " + user_address) split_address = user_address. split() print(split_address) Output Interactively, it asks the user to enter the address. After the code runs, the address splits i...

Here are the Python pickling and unpickling best examples and the differences between these two. These you can use to serialize and deserialize the python data structures. The concept of writing the total state of an object to the file is called  pickling,  and to read a Total Object from the file is called  unpickling. Pickle and Unpickle The process of writing the state of an object to the file (converting a class object into a byte stream) and storing it in the file is called pickling. It is also called object serialization . The process of reading the state of an object from the file ( converting a byte stream back into a class object) is called unpickling.  It is an inverse operation of pickling. It is also called object deserialization .  The pickling and unpickling can implement by using a pickling module since binary files support byte streams. Pickling and unpickling should be possible using binary files. Data types you can pickle Integers Boolea...

Date and Time how to get and how to use is well needed in a software project. So in Python, you can find these features. Date and Time Features in Python Date feature you need it to get Date in the coding. Here the point is the Date and how to get it, and the various formats of it. Generally, you will find three different Date and Time formats. Before going into detail, here are those formats. Date and Time formats Epoch: It is a point where the time starts and is dependent on the platform. It is taken as January 1st of the current year, 00:00:00. But for UNIX systems, it is 1st January, 1970, 00:00:00 (UTC). UTC: UTC means Coordinated Universal Time (also known as Greenwich Mean Time) and is a compromise between English and French. DST: It is Daylight Saving Time which is an adjustment of the time zone by one hour during part of the year. In other words, the clock is forward by one hour in the spring and backward by one hour in the autumn to return to standard time. 1. How to get the ...

Here are the differences between Class and Interface in Python. Python class can have all concrete methods. But interface does not have single concrete method. Here you'll know about What's abstract method Abstract Class: How to Create it Rules to Write an Interface How to Create Abstract Class How to Create an Interface What's abstract method The abstrcat method is one which does not have body. from abc import ABC, abstract method class name_class(ABC): # abstract class @abstractmethod def name_method(self): #abstract method without body pass The interface is used when all the features are needed to be implemented differently for different objects. Rules to Write an Interface All methods of an interface should be abstract. You cannot create an interface object. If any class implements an interface, then you need to define all the methods given in that interface in child class. You need to declare all methods as abstract if that class does not implement the interface How to...

Here are three access modifiers in Python - Public, Protect, and Private. Access modifiers control the access to a variable/or method.  You may have a question that does python supports access modifiers? The answer is yes. In general, all the variables/or methods are public. Which means accessible to other classes. The private and protect access modifiers will have some rules. And the notation for protect and private are different. The single underscore is for protected and the double underscore is for private. Here is how to find Python list frequent items. Differences between Public, Protect and Private Public access modifier Public variables are accessible outside the class. So in the output, the variables are displayed. class My_employee:     def __init__(self, my_name, my_age):         self.my_name = my_name  #public         self.my_age = my_age   # public my_emp = My_employee('Raj',34) print(my_emp.my_name) prin...

Here is an example of complex python program written using functions. Many times, in job interviews, you need to give a written test. There, you may need to answer tricky programs. Historically, people are afraid to take a test.  Especially in python .  Complex Python programs Below are the Complex Python Program Using Functions and examples of how to write the code. Counting lower and upper case letters Creating a list 1. Counting lower and upper case letters Below program counts the upper and lower case letters. def count_lower_upper(s): dlu = {'Lower': 0, 'Upper': 0} for ch in s: if ch.islower(): dlu['Lower'] += 1 elif ch.isupper(): dlu['Upper'] += 1 return(dlu) d = count_lower_upper('James BOnd') print(d) d = count_lower_upper('Anant Amrut Mahalle') print(d) Also read : How to Lose Your Weight 2. Creating a List Here it uses two input lists for creating a new list. Additionall...

Here is the logic for searching single CHAR using regular expression(Regex). For instance, we use wildcards to search for anything on our computers. The Regex in Python works similarly. Regular expression People use asterisk * for searching any document. For instance, if you type *.pdf, it returns all the pdfs available in the location (where you are conducting your search). Similar way, in Python, you can search using regular expressions. Import Regex  The first thing you need to do is import 're' if you want to work with regular expressions. import re The Python regular expression library, you can use to improve your skills. Example program: search for single CHAR To match any single character, you can use  [….] . Below, you will find an example to search for: 'l' or 'a' or 'b' import re pattern = r'[lab]' sequence = 'we love python' obj = re.search(pattern,sequence) if obj: print("We found a match here @",obj.group()) else: p...

Here are the tricky examples of list comprehension. These examples useful for your project and interviews as well. 1. Printing odd numbers Reminder checking logic used here. If it is not equal to zero when you divide the number with 2, it treats the input number as odd and prints it. lst1 = [x for x in range(40) if x % 2 != 0] print('First 20 Odd Numbers:') print(lst1) 2. Printing even numbers Reminder checking logic used here. If it is equal to zero when you divide the number with 2, it treats the input number as even and prints it. lst2 = [x for x in range(40) if x % 2 == 0] print('First 20 Even Numbers:') print(lst2) Output from the Python scripts First 20 Odd Numbers:  [1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39] First 20 Even Numbers:  [0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36, 38]  ** Process exited - Return Code: 0 ** Press Enter to exit terminal Related The real use of Git in Dev Ops