Python Tutorial Notes

Introduction

• Learn Python programming from scratch.
• No prior knowledge needed.
• Mosh Hamadani as the instructor.
• Subscribe for weekly updates.

What Can You Do with Python?

• Python is a multi-purpose programming language.
• Uses include:
  • Machine Learning & AI.
  • Data Science projects.
  • Web Development using Django.
• Examples of websites using Python & Django:
  • YouTube
  • Instagram
  • Spotify
  • Dropbox
  • Pinterest
• Automation of repetitive tasks to increase productivity.

Setting Up Python

Downloading Python

1. Visit python.org.
2. Navigate to Downloads and select the latest version.
3. Install the Python installer:
   • On Windows: Check "Add Python to PATH".
   • Agree to terms and install.

Installing a Code Editor

• Use PyCharm for writing and executing code.

1. Visit jetbrains.com/pycharm.
2. Download the Community Edition (free).
3. Install PyCharm:
   • On Windows: Follow the installation wizard.
   • On Mac: Drag to Applications folder.
4. Configure settings on first run and create a new project.

Writing Your First Python Code

Hello World

• Create a new Python file and write:

  print("Hello World")
  

• Run the code to see output in the terminal.

Variables

• Used to store data temporarily.
• Syntax to declare variables:

  age = 20
  

• Print the value of a variable:

  print(age)
  

Types of Values

• Integer: Whole numbers.
• Float: Numbers with a decimal point.
• String: Textual data (enclosed in quotes).
• Boolean: true or false.
  • Case-sensitive (True, False).

User Input

• Use input() function to receive input:

  name = input("What is your name? ")
  print("Hello " + name)
  

Data Type Conversion

• To convert string to integer or float:

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

Arithmetic Operations

• Common operators include +, -, *, /, // (integer division), % (modulus), ** (exponent).
• Operator precedence matters—use parentheses to control order.

Comparison Operators

• Used to compare values:

  • , >=, <, <=, == (equal), != (not equal).

Logical Operators

• Combine comparisons:
  • and, or, not.

Control Flow

If Statements

• Used for decision-making:

  if temperature > 30:
      print("It's a hot day")
  elif temperature > 20:
      print("It's a nice day")
  else:
      print("It's a cold day")
  

Loops

While Loops

• Repeats a block of code:

  i = 1
  while i <= 5:
      print(i)
      i += 1
  

For Loops

• Iterates over a sequence:

  for num in range(1, 6):
      print(num)
  

Lists

• Used to store collections of items:

  names = ["John", "Bob", "Marsh"]
  

• Access elements by index (0-based), modify elements, append/remove items.

Using Built-in Functions

• len() for length of the list.
• Using in to check for existence in list.

Tuples

• Similar to lists but immutable:

  numbers = (1, 2, 3)
  

• Fewer methods available than lists.

Conclusion

• Recap of Python basics covered in this tutorial.
• Encourages continued learning through structured courses available on the instructor’s platform.