Introduction to Python Course by Mosh

Introduction to Python

• Instructor: Mosh
• Course Goal: Learn programming in Python
• Importance of Python: Popular for automation, AI, building applications/websites (e.g., Instagram, Dropbox)
• Target Audience: Beginners looking for a job
• Course Outline: Core Python concepts, three Python projects

First Project: Grocery Store Website

• Goal: Create a website for an imaginary grocery store
• Features: Homepage showing products, admin area for stock management
• Framework: Django
• Approach: Teach everything from scratch

Second Project: Predicting Music Preferences

• Goal: Write a Python program to predict music preferences based on profiles
• Inspiration: Similar to how YouTube recommends videos
• Application: Machine learning (AI)

Third Project: Automate Spreadsheet Processing

• Goal: Automate processing thousands of spreadsheets in seconds
• Application: Automate repetitive tasks

Python Installation

• Website: python.org
• Steps: Download the latest version, ensure Python is added to PATH (Windows), Install via setup wizard (Mac)

Code Editor: PyCharm

• Website: jetbrains.com/pycharm
• Editions: Professional (paid), Community (free)
• Installation: Download and install, set base interpreter to Python 3
• Using PyCharm: Create a project and a Python file (e.g., app.py)

Writing and Running Python Programs

• First Program: Print your name using print() function
• Shortcut to Run: Control + Option + R (Mac), different for Windows

Drawing with Python

• Example: Drawing a dog using print() and special characters

Calculating Age

• Example Program: Calculate age by entering birth year
• Handling Input: Use input() and int() for conversion
• Error Handling: Convert strings to integers to perform calculations

Variables in Python

• Concept: Temporarily store data (e.g., price = 10)
• Types: Integers, Floats, Strings, Booleans
• Example: Program for hospital patient management

User Input in Python

• Example Program: Ask for user’s name, favorite color, and print a personalized message
• Quick Tips: Use input(), string concatenation, and formatted strings

Python Cheat Sheet

• Resource: Summary notes and cheat sheet provided
• Suggestion: Support by liking, sharing, and subscribing

Calculating Weight Conversion

• Example Program: Convert weight from pounds to kilograms
• Handling Errors: Use int() or float() to avoid multiplication errors

Python Strings

• Defining Strings: Single or double quotes, triple quotes for multi-line
• Indexing: Access characters using positive/negative indices
• Slicing: Extract substrings using : operator
• Methods: .upper(), .lower(), .find(), .replace(), in operator

Arithmetic Operations

• Operators: Addition (+), Subtraction (-), Multiplication (*), Division (/), Modulus (%), Exponent (**)
• Precedence: Define the order of operations
• Augmented Assignment: Shorter form of operations (e.g., x += 3)

Conditional Statements

• If Statements: Execute code based on conditions
• Example: Determine if it’s a hot, cold, or lovely day
• Logical Operators: And, OR, NOT
• Relational Operators: Evaluate conditions (e.g., >=, ==, !=)

Practical Exercises

• Variables, Strings, Conditions: Several example challenges (e.g., name validation, weight conversion)

Loops

• While Loops: Execute code multiple times based on a condition
• For Loops: Iterate over collections (e.g., strings, lists)
• Examples: Total cost of items in a shopping cart, nested loops for generating coordinates

Lists in Python

• Concept: Ordered collection of items (e.g., [1, 2, 3])
• Accessing Items: Use indices, slicing
• Modifying Lists: Add, remove, sort, and copy items
• Example Exercise: Find the largest number in a list, remove duplicates

Tuples in Python

• Concept: Immutable lists (cannot change items)
• Applications: Use when data should not be modified

Dictionaries in Python

• Concept: Store key-value pairs (e.g., {key: value})
• Accessing Items: Use keys
• Modifying Dictionaries: Add, update, delete items
• Example Exercise: Phone number to words conversion
• Advanced Use: Emoji converter

Functions in Python

• Definition: Reusable code blocks
• Parameters and Arguments: Passing information to functions
• Return Values: Functions returning results
• Organizing Code: Extracting functions to improve code readability and reusability

Python Modules and Packages

• Modules: Organize code into separate files
• Packages: Organize related modules into directories
• Built-in Modules: E.g., random, math
• Using External Packages: Install via pip (e.g., openpyxl for Excel files)

File and Directory Management

• Pathlib Module: Work with file-system paths
• Examples: Create, delete, iterate through files/directories

Automation with Python

• Project: Automate data processing in Excel
• Libraries: openpyxl, matplotlib
• Steps: Load, process data, save results, generate charts
• Practical Application: Reduce manual repetitive tasks

Machine Learning

• Concepts: Model, training, prediction
• Libraries: Numpy, Pandas, Matplotlib, Scikit-Learn
• Tools: Jupyter notebooks for data analysis and visualization
• Steps: Importing, cleaning, training, validating data
• Example Project: Predict music preferences based on user profiles

Web Development with Django

• Introduction: Popular web framework for building scalable and secure web applications
• Installation: Using pip (e.g., pip install django==2.1)
• Creating Projects: Using django-admin command