Python Programming Tutorial Notes

Introduction

• Instructor: Mosh Hamadani
• Objective: Teach Python programming from scratch for various applications (data science, machine learning, web development).
• No prior knowledge required.

What Can You Do With Python?

• Multi-purpose programming language.
• Machine Learning and AI: Python is the leading language for these fields.
• Web Development: Popular frameworks like Django.
  • Examples of sites powered by Python: YouTube, Instagram, Spotify, Dropbox, Pinterest.
• Automation: Automate repetitive tasks to save time and increase productivity.

Setting Up Python

1. Visit python.org to download the latest version.
   • Check the box to "Add Python to PATH" during installation.
2. Download a code editor.
   • Recommended: PyCharm.
   • Choose Community Edition (free).
3. Create a new Python project in PyCharm.
   • Name the project (e.g., HelloWorld).

Writing Your First Code

• Creating a Python File: Right-click on the project name, create a new Python file (e.g., app.py).
• Printing Output: Use print("Hello, World!") to display output.
  • Strings: Textual data enclosed in quotes.
• Running Code: Use the Run menu or shortcuts.

Variables

• Definition: Temporarily store data.
• Declaration: age = 20
• Printing Variables: Use print(age) to display the value.
• Changing Variables: Reassign values (e.g., age = 30).
• Variable Naming: Use underscores for multiple words (e.g., first_name).
• Boolean Values: Examples include is_online = True or is_online = False.

User Input

• Use input() function to receive user input.
  • Example: name = input("What is your name? ")
• Concatenate strings using + (e.g., print("Hello, " + name)).

Data Types

1. Numbers: Integers and floats.
2. Strings: Text data.
3. Booleans: True or False.
4. Type Conversion: Convert data types using int(), float(), str(), etc.

Arithmetic Operations

• Basic operations: +, -, *, /, // (integer division), % (modulus), ** (exponentiation).
• Augmented Assignment Operators: Simplify assignments (e.g., x += 3).

Comparison Operators

• Used to compare values: >, <, >=, <=, ==, !=.

Logical Operators

• Used for complex conditions: and, or, not.

If Statements

• Structure:

  if condition:
      # code to execute if condition is true
  elif another_condition:
      # another code block
  else:
      # code if no conditions are true
  

Loops

• While Loops: Repeat code while a condition is true.

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

• For Loops: Iterate over a sequence (like a list or range).

  for item in sequence:
      print(item)
  

Lists

• Definition: Ordered collection of objects.
• Creating a List: names = ["John", "Bob", "Marsh"]
• Accessing Elements: Use indexing (e.g., names[0]).
• List Methods: append(), insert(), remove(), clear(), etc.

Tuples

• Definition: Similar to lists but immutable (cannot be changed).
• Use parentheses to define: numbers = (1, 2, 3).

Functions

• Built-in Functions: len(), range(), etc.
• Creating Functions: def function_name(): to define a custom function.

Conclusion

• Python is versatile and used for various applications.
• Practice is key to mastering programming concepts.