Python Programming Tutorial Notes

Introduction

• Learn Python from scratch
• Applicable for data science, machine learning, web development
• No prior knowledge required
• Instructor: Mosh Hamadani
• Subscribe for weekly updates

What Can You Do With Python?

• Multi-purpose programming language
• Common uses:
  • Machine Learning & AI
  • Web Development (popular frameworks: Django)
  • Automation of repetitive tasks
• Examples of websites built with Python & Django:
  • YouTube
  • Instagram
  • Spotify
  • Dropbox
  • Pinterest

Installing Python

1. Go to python.org
2. Download the latest version
3. Important: Check "Add Python to PATH" during installation

Installing a Code Editor

• Recommended: PyCharm
• Download from JetBrains
• Community Edition is free
• Configure settings on the first launch
• Create a new project and name it (e.g., "Hello World")

Writing Your First Python Code

• Create a new Python file
• Code to print "Hello World":

  print("Hello World")  
  

• Run the code via the run menu or shortcuts

Understanding Variables

• Variables store data in memory
• Example of variable declaration:

  age = 20  
  

• Print variable value:

  print(age)  
  

• Variable names: Use underscores for multiple words

Data Types

1. Strings
   • Textual data enclosed in quotes
2. Booleans
   • True or False
   • Case sensitive (True vs true)
3. Numbers
   • Integers and floats (e.g., 19.95)

User Input

• Use input() to read values from the terminal
• Example:

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

Type Conversion

• Use built-in functions:
  • int() to convert to integer
  • float() to convert to float
  • str() to convert to string

Arithmetic Operations

• Basic operators: +, -, *, /
• Integer division (//) and modulus (%)
• Operator precedence (use parentheses to change order)

Conditional Statements

• Use if, elif, and else for decision making
• Example:

  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 loop example:

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

• for loop example to iterate over a list

  for item in names:  
      print(item)  
  

Lists

• Store multiple items in a single variable
• Example:

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

• Access items by index, use append(), insert(), remove(), clear(), and in operator
• Length of a list: len(list)

Tuples

• Similar to lists but immutable
• Use parentheses to define:

  numbers = (1, 2, 3)  
  

• Limited methods compared to lists

Conclusion

• Python is versatile and beginner-friendly
• Essential for various applications and use cases
• Resources for further learning are available at codewoodmosh.com