Lab 3f — Structured Data

Yelp

15 minutes

You are provided with starter code (yelp.py) for an app that queries the user for a list of restaurants and ratings and then identifies which restaurant to go to.

Discussion

Notice the structure of the app: the main function breaks the problem down into three steps:

• Get the ratings
• Find the highest-rated restaurant
• Print the result

What kind of data does pick_highest(ratings) expect? Is it a string? An integer? A list? A list of what?

What kind of data should get_ratings() return? From the code we can see it returns a list, but a list of what?

What should get_rating_info() return? How should it create that information?

Implement

Now implement get_rating_info and pick_highest. Look at the examples in the guide if you need inspiration: Lists of tuples

Testing

Run your app. Test it with different restaurant names and scores.

You should be able to see something like this:

Restaurant: Supreme Burger
Rating: 5
Restaurant: Wendy's
Rating: 3.5
Restaurant: Costa Vida
Rating: 4.5
Restaurant: 
Supreme Burger is rated 5.0 stars.

Highest Predicted Return on Investment

20 minutes

A house flipper is deciding which house to buy, fix, and sell. Help them find the house that will yield the most profit.

The user will enter houses like this:

Address: 123 800 S Provo
Purchase price: 82000
After repair value: 98000
Cost to repair: 10000
Project duration: 1

Address: 321 400 N Orem
Purchase price: 112000
After repair value: 140000
Cost to repair: 15000
Project duration: 6

Address:

This is the function to calculate the expected profit.

def get_profit(house):
    address, purchase_price, after_repair_value, cost_to_repair, project_duration = house
    monthly_property_taxes = purchase_price / 1000
    cost_of_sale = 3000
    costs = purchase_price + cost_to_repair
    costs += monthly_property_taxes * project_duration
    costs += cost_of_sale
    return after_repair_value - costs

Select the house that will return the most profit, and display it like this:

Expected profit: $9328.0

Address: 321 400 N Orem
Purchase price: $112000.0
After repair value: $140000.0
Cost to repair: $15000.0
Project duration: 6.0 months

Tips

• Describe the inputs and outputs of each function
• What functions should main call? What functions should be called by those functions?
• When finding the “best” house, how will you use the get_profit function?
  • You’ll want to keep track of the max_profit so far, and update it when you find a house with better profit.
  • Use a similar pattern to what you used in yelp.py

Maximizing Monthly Income

5 minutes

Modify the previous code so that you return the highest profit per month. The highets profit per month can be calculated like this: profit_per_month = profit / project_duration.

Make a new function, called profit_per_month(), that uses the get_profit() function you already created.

Change the program to print the house with the highest profit per month:

Expected profit per month: $2918.0

Address: Provo
Purchase price: $82000.0
After repair value: $98000.0
Cost to repair: $10000.0
Project duration: 1.0 months