OIM3600 - Computer Science for Business Students

Session 13 (10/09)

Today's Agenda

• Welcome/News/Announcements
• Class Review
• How to Debug
• Lectures:
  • Python Programming (cont.)
    • Data structures: list, dict, tuple, set
  • API
    • Notice: you should've created an API key from OpenWeather.

Welcome/News/Announcements

• Homework feedback will be provided in your GitHub issues or via PR.
  • Please respond.
• Make sure you understand the code you use in your exercises and homework.
  • i.e. I may ask you to come to my office and explain any code that looks "interesting".
• Communications:
  • Slack - for debugging, clarifications, real-time discussion, casual chat, etc.
  • Email - specify course # in subject title, e.g., "OIM3600: GitHub settings"
  • Meet with me in person during office hours at least once this semester.
• Questions?

What we have learned so far

• Code represent:
• Scratch
• Git/GitHub
• Programming
  • Functions: arguments, side effects, return values
  • Conditionals
  • Boolean expressions
  • Loops
  • Variables
  • Types: int, float, string, boolean, Nonetype, list, dict, ...
  • I/O

Homework Feedback & Coding Style

• GitHub Issues
  • Reply with feedback or questions if further discussion is needed.
  • Reply with evidence (e.g., code, screenshots) and close if resolved.
• Functionality
  • Use pseudocode for complex or unclear code/algorithms.
  • Write additional test code when necessary.
• Documentation
  • Add docstrings for every function that you create.
  • Write clear and relevant comments.
• Styles
  • Use lowercase and underscore for folder and file names.
  • Choose clear and meaningful variable and function names.

How to Debug

• Format code first: Alt (⌥ option if macOS) + Shift + F in VSCode.
• print()
• PythonTutor.com
• Debugging in VS Code
  1. Set breakpoints
  2. Run debugger: Press F5 to Start Debugging
     1. "Continue" ( F5 ): Keep running until you hit a stopping point.
     2. "Step Over" ( F10 ): Go through code line by line, skip functions.
     3. "Step Into" ( F11 ): Go inside functions and trace their lines.
  3. Inspect Variables: Use "VARIABLES" panel or "WATCH" panel.

Lectures

• Python Programming (cont.)

Conversions Between Data Structure Types

1. string ⇔ list
2. string ⇔ dictionary
3. string ⇔ tuple
4. string ⇔ set
5. list ⇔ dictionary
6. list ⇔ tuple
7. list ⇔ set
8. dictionary ⇔ tuple
9. ...

API (Application Programming Interface)

• An API is a set of protocols, tools, and standards that allow different software applications to communicate with each other.
• Read/Watch:
  • What is an API? In English, please.
  • YouTube - What is an API and how does it work? (In plain English)
• Example: Let's say you want to know the current price of Bitcoin
  • Human: Opens a browser, searches "Bitcoin price", and checks websites.
  • Computer: Sends a request to an API and gets Bitcoin price in JSON format.
    • Example API endpoint: https://api.coindesk.com/v1/bpi/currentprice.json

API Example: OpenWeather

• Get an API key from https://openweathermap.org/api
• Download the sample code, weather.py, from resources/code
• Use the urllib.request library to send HTTP requests to the OpenWeather API and retrieve data in JSON format
• Remember to protect sensitive data (e.g., API keys, API tokens, passwords)
  • Create .env file and store your API key, e.g., OPENWEATHER_API_KEY=...
  • Install python-dotenv in Terminal: python -m pip install python-dotenv

  • import os
    from dotenv import load_dotenv
    
    load_dotenv()
    APIKEY = os.getenv("OPENWEATHER_API_KEY")
    

  • Add .env to the .gitignore to prevent committing it to a public repository.