Python Crash Course

Introduction

• Learn as much Python as possible in one hour.
• Ideal for those transitioning from other programming languages.
• Additional full, free 12-hour course available.

Setup

Download Python Interpreter

• Visit python.org
• Go to Downloads and download the latest version.
• On Windows, check the box to add Python to PATH.
• Run the executable to complete installation.

Download IDE (Integrated Development Environment)

• Two popular choices: PyCharm and VS Code.
  • PyCharm is more beginner-friendly.
    • Download the Community Version.
    • Follow installation prompts.
  • VS Code can also be used, but requires Python extension.

Creating Your First Python Project

• Open IDE (e.g., PyCharm) and create a new project.
• Create a new Python file (e.g., Main.py).

Writing Code

• Use the print() function:

  print("I like pizza")
  

• Output: Displays "I like pizza" in console.
• Add multiple print statements:

  print("It's really good")
  

Comments

• Use # for comments:

  # This is my first Python program
  

• Comments do not affect output.

Variables

Definition

• Variables are reusable containers for values.
• Four data types: Strings, Integers, Floats, Booleans.

Creating Variables

• Example:

  full_name = "Your Name"
  

• Use f-strings for formatted output:

  print(f"Hello, {full_name}")
  

Data Types Explained

• Strings: Series of characters.
• Integers: Whole numbers (e.g., 25).
• Floats: Numbers with decimals (e.g., 3.2).
• Booleans: True or False values.

Basic Arithmetic

• Arithmetic Operators:
  • Addition (+)
  • Subtraction (-)
  • Multiplication (*)
  • Division (/)
  • Integer Division (//)
  • Modulus (%)

Example Usage

friends = 5
friends += 1  # Increment
print(friends)  # Output: 6

Typecasting

Definition

• Converting a variable from one data type to another.

Functions for Typecasting:

• str(), int(), float(), bool()
• Example:

  age = int(input("Enter your age:"))
  

User Input

• Use the input() function to accept user input:

  name = input("Enter your name:")
  

• Input is always a string by default. Typecast if necessary.

Conditional Statements: If Statements

Basic Structure

if condition:
    # code to execute if condition is true
else:
    # code to execute if condition is false

Example:

if age >= 18:
    print("You are an adult")
else:
    print("You are a child")

Logical Operators

• OR: At least one condition must be true.
• AND: Both conditions must be true.
• NOT: Inverts the condition.

Loops

While Loops

• Repeat code while a condition is true.

while condition:
    # code to repeat

For Loops

• Iterate over a sequence or a range.

for i in range(10):
    print(i)

Data Structures

Lists

• Mutable collections defined by square brackets.
• Supports indexing, appending, and removing elements.

Tuples

• Immutable collections defined by parentheses.
• Faster access than lists but cannot change.

Sets

• Unordered collections defined by curly braces.
• Unique items only, no duplicates allowed.
• Good for membership testing.

Summary

• Python is versatile and beginner-friendly.
• Fundamental concepts: Variables, Control Flow, Loops, Data Structures.