String Manipulation in Python

String manipulation is a crucial aspect of working with textual data in Python. Strings are sequences of characters and are immutable, meaning they cannot be changed after they are created. Python provides various string manipulation techniques to perform operations like slicing, concatenation, formatting, and utilizing built-in string methods to modify and manipulate strings efficiently.

Common String Manipulation Techniques:

• Slicing: Slicing allows you to extract a substring from a string based on its indices. You can use slicing to get a specific portion of a string.
• Concatenation: Concatenation is the process of combining two or more strings to create a new string. You can concatenate strings using the + operator.
• String Formatting: String formatting allows you to construct dynamic strings by inserting values into placeholders. Python supports several ways of string formatting, including f-strings, str.format(), and % operator.
• Built-in String Methods: Python provides a variety of built-in string methods like upper(), lower(), replace(), split(), find(), count(), and more, which allow you to manipulate and analyze strings efficiently.

1. Slicing:

        
            # Slicing allows you to extract a substring from a string based on its indices.
            text = "Hello, World!"
            # Extract the substring "Hello"
            substring1 = text[0:5]
            # Extract the substring "World!"
            substring2 = text[7:]
            print(substring1)  # Output: "Hello"
            print(substring2)  # Output: "World!"
        
    

2. Concatenation:

        
            # Concatenation is the process of combining two or more strings to create a new string.
            first_name = "John"
            last_name = "Doe"
            full_name = first_name + " " + last_name
            print(full_name)  # Output: "John Doe"
        
    

3. String Formatting:

        
            # String formatting allows you to construct dynamic strings by inserting values into placeholders.
            name = "Alice"
            age = 30
            # Using f-string (Python 3.6+)
            formatted_string1 = f"My name is {name} and I am {age} years old."
            # Using str.format()
            formatted_string2 = "My name is {} and I am {} years old.".format(name, age)
            # Using % operator (old style)
            formatted_string3 = "My name is %s and I am %d years old." % (name, age)
            print(formatted_string1)  # Output: "My name is Alice and I am 30 years old."
            print(formatted_string2)  # Output: "My name is Alice and I am 30 years old."
            print(formatted_string3)  # Output: "My name is Alice and I am 30 years old."
        
    

4. Built-in String Methods:

        
            # Python provides a variety of built-in string methods for string manipulation.
            text = "Hello, World!"
            # Convert to uppercase
            uppercase_text = text.upper()
            # Convert to lowercase
            lowercase_text = text.lower()
            # Replace "Hello" with "Hi"
            replaced_text = text.replace("Hello", "Hi")
            # Split the string into a list of words
            words = text.split()
            # Find the index of "World" in the string
            index = text.find("World")
            # Count the occurrences of "l" in the string
            count_l = text.count("l")
            print(uppercase_text)  # Output: "HELLO, WORLD!"
            print(lowercase_text)  # Output: "hello, world!"
            print(replaced_text)   # Output: "Hi, World!"
            print(words)           # Output: ['Hello,', 'World!']
            print(index)           # Output: 7
            print(count_l)         # Output: 3
        
    

Instructions:

To work on the exercises, follow these steps:

1. Read the problem statement for each exercise and understand the expected input and output.
2. Write Python code for each exercise in your favorite text editor or IDE.
3. Save the code in a .py file, e.g., exercises.py
4. Run the Python file using the Python interpreter.
5. Observe the outputs and verify that the results match the expected outputs mentioned in each exercise.
6. Modify the code as needed to achieve the desired results.
7. Have fun and experiment with different string manipulation techniques!

Advanced Exercises:

1. Title Capitalization:

                   Input: "hello world, how are you?"
                   Output: "Hello World, How Are You?"
               

2. Word Frequency Counter:

                   Input: "Python is a popular programming language. Python is versatile and powerful."
                   Output: {'Python': 2, 'is': 2, 'a': 1, 'popular': 1, 'programming': 1, 'language': 1, 'versatile': 1, 'and': 1, 'powerful': 1}
               

3. Caesar Cipher Encryption and Decryption:

                   Input: "hello", Shift: 3
                   Output: "khoor"
               

4. Password Generator:

                   Input: length = 12
                   Output: "aB2@yC#7zEf1"
               

5. Word Reversal:

                   Input: "Hello World"
                   Output: "olleH dlroW"
               

6. String Compression:

                   Input: "aaabbcccddddeee"
                   Output: "a3b2c3d4e3"
               

7. Anagram Checker:

                   Input: "listen", "silent"
                   Output: True
               

Python string manipulation for beginners YouTube Video