Python Basics

Module 1: Python Basics

• Covers the fundamentals of Python programming.
• Topics include program development cycle, input/output, comments, variables, data types, calculations, formatting, constants, and turtle graphics.

Program Development Cycle

• Involves designing, coding, testing, and debugging.
• Steps: Design, write code, correct syntax errors, test for logic errors, and fix errors.

Basic Input & Output

• print("Hello, World!") displays output.
• name = input("Enter your name: ") reads user input as a string.

Data Types & Variables

• Integer: int, e.g., x = 10.
• Float: float, e.g., pi = 3.14.
• String: str, e.g., name = "Alice".
• Boolean: bool, e.g., is_active = True.

Performing Calculations

• Addition: sum = a + b
• Subtraction: diff = a - b
• Multiplication: product = a * b
• Division: quotient = a / b

Comments in Python

• Single-line comments start with #.
• Multi-line comments are enclosed in triple quotes """.

Turtle Graphics

• The turtle module allows for simple drawing.
• import turtle imports the module.
• turtle.forward(100) moves the turtle forward 100 units.
• turtle.right(90) turns the turtle 90 degrees to the right.
• turtle.done() completes the drawing.

Module 2: Getting Inputs

• Focuses on accepting and processing user input.
• Covers reading input, naming rules, converting input to numbers, using int() and float(), and string formatting.

Reading User Input

• name = input("Enter your name: ") prompts the user for input.
• print("Hello, " + name + "!") displays a greeting with the user's name.

Variable Naming Rules

• Valid names: user_name, age, totalAmount.
• Invalid names: 99bottles (starts with a number), r&d (special characters).

Reading Numeric Input

• input() returns a string by default, it must be converted to an Integer or Float.
• age = int(input("Enter your age: ")) converts input to an integer.
• height = float(input("Enter your height: ")) converts input to a float.

Module 3: Decision Structures (Conditions)

• Explains how to write programs that make decisions.
• Covers if, if-else, if-elif-else statements, comparing strings, logical operators, and boolean variables.

If Statement

• if age >= 18: print("You can vote.") executes the print statement if the condition is true.

If-Else Statement

• Allows you to chose between 2 options.
• If the condition is true the first statement is run, otherwise the second is run.
• python CopyEdit if age >= 18: print("You can vote.") else: print("You cannot vote.")

Logical Operators

• if age > 18 and age < 60: print("You are an adult.") checks if both conditions are true.

Module 4: Repetition Structures (Loops)

• Introduces loops for repeated execution of code.
• Topics include loops, while loop, for loop, loop control statements, and nested loops.

While Loop

• while x < 5: print(x); x += 1 continues executing as long as the condition is true.

For Loop

• for i in range(5): print(i) iterates through a sequence.

Loop Control Statements

• break exits the loop immediately.
• continue skips the current iteration.
• pass does nothing (placeholder).

Module 5: Functions

• Functions facilitates modular programming by breaking code into reusable blocks.
• Includes defining, calling, parameters, return values, and local vs global variables.

Defining & Calling Functions

• def greet(): print("Hello!") defines a function.
• greet() calls the function.

Returning Values

• def add(a, b): return a + b defines a function that returns a value.
• result = add(5, 3); print(result) calls the function and displays the result.

Module 6: Lists & Tuples

• Data structures that store multiple values.
• Covers lists, indexing, slicing, methods, iteration, tuples, and operations.

Lists ([])

• numbers = [1, 2, 3, 4, 5] creates a list.
• numbers.append(6) adds 6 to the list.

Tuples (())

• Tuples are immutable (cannot change).
• my_tuple = (1, 2, 3) creates a tuple.

List vs Tuple Comparison

• Lists are mutable (can change), tuples are immutable (cannot change).
• Lists are slower, tuples are faster.

Object-Oriented Programming (OOP)

• OOP groups related data (attributes) and actions (functions) into objects.

Objects and Classes

• An object has properties and can perform actions; a dog has a breed (property) and can bark (action).
• A class is a blueprint for creating objects.

Character Class Example

• Class example: python CopyEdit class Character: name = "Default Name" hp = 100 atk = 10

Creating an Object

• Creates a new character object: python CopyEdit character1 = Character() print(character1.name) # Output: Default Name

Changing Attributes

• Can modify the object's attributes after creating it: python CopyEdit character1.name = "Alenere" character1.hp = 120 print(character1.name) # Output: Alenere print(character1.hp) # Output: 120

Constructor (init)

• Sets the object value as its being created: python CopyEdit class Character: def init(self, name, hp, atk): self.name = name self.hp = hp self.atk = atk character1 = Character("Alenere", 120, 15) character2 = Character("Scar", 100, 18) print(character1.name) # Output: Alenere print(character2.name) # Output: Scar

Functions for Objects

• A class can also have functions (methods): python CopyEdit class Animal: def init(self, type, sound): self.type = type self.sound = sound def speak(self): # A function inside the class print(self.sound) animal1 = Animal("Dog", "Bark") animal2 = Animal("Cat", "Meow") animal1.speak() # Output: Bark animal2.speak() # Output: Meow

Self Keyword

• self refers to the object itself and is how it stores its information.
• self.name stores the name
• self.hp stores the HP
• self.atk stores the attack power

Why Use Classes and Objects?

• Organizes code by grouping related actions and data.
• Promotes reusability by making new objects.
• Eases maintenance updating work by making class changes easy to update.

Final Summary

• Objects have actions and attributes.
• Classes are object blueprints.
• __init__ (Constructor) sets object values.
• Functions inside a class defines objects.
• self keyword refers to the object.