HW: Dictionaries and While Loops

Purpose: Learn how to create a dictionary and how to call information from it.

Getting Started

Create a copy of the starter sheet here: Open In Colab

Rename it something like "(Your_Name)_HW_Dict_While.ipynb".

Part 1 - Dictionary Creation

In this assignment, you will be creating a dictionary and using it to calculate the cost of materials and shipping. The dictionary will contain the cost of each material per ton and the cost to ship each material per mile. You will then use this dictionary to calculate the total cost of a shipment of materials.

  1. In the first code block, make a dictionary called MaterialsDictionary. Use the following keys and their corresponding values to populate the dictionary:
Key Value
"Guide" ["$ per ton","$ ship per mile"]
“Steel” [700,5]
“Cement” [130,2]
"Lumber" [34,4]
"Glass" [50,15]

Part 2 - Function Definition

  1. In the second code block, there is a function called "invoice_calc" that will calculate the total cost of a shipment of materials.
  2. The function takes two parameters: a dictionary (titled MaterialsDictionary) and the number of different materials that the user has requested to buy (a variable titled amountmat). The function will return the total cost of the shipment. The structure of the function is already set up for you.

Part 3 - For Loop

  1. In the function (where it says "Write the first for loop starting here"), write a for loop that loops through the materials in the MaterialsDictionary. Make sure that you start writing your code with at least one indentation since it is within a function.

  2. In the for loop, use an if statement to ensure that the key is not equal to "Guide." Create two variables that you will reference in a print statement. One variable should reference the cost per ton value in the dictionary, and the second variable should reference the $ ship per mile. Create a print statement that loops through each material and states how much each material costs per ton and how much it costs to ship.

Part 4 - While Loop

  1. In the function where it says "Write the while loop starting here," write a while loop that will iterate however many items the user ordered, asking: 1) what material, 2) how many tons, 3) how many miles it will be shipped.

Hint

In the table below we provide some guidance for the input statements. You need to convert any numbers entered to float variable type, as any input to an input statement assumes everything is a string.

  1. In the while loop, create the following input statements:
Variable Name Prompt Variable Type
material Asks what material the user wants to buy string
quantity Asks how much of that material the user wants to buy in tons float
distance Asks how far the material will be shipped in miles float

Hint

Use the .capitalize() function so that you don't have to worry about capitalization problems with your materials!

  1. Create an if statement that checks if the user has inputted a valid material. If the material is not in the dictionary, print a message that says "Material not found. Please enter a valid material." and use the continue statement to skip to the next iteration of the loop. Make sure the count does not increase if the material is not found.

  2. Still in the loop, add the cost of the material multiplied by its quantity to the cost of shipping the material multiplied by its distance. Store this in a variable that represents the item cost.

  3. Add each item cost to the variable "total" that was already included in the function.

Hint

Use the += operator when adding the costs to the total.

  1. Make sure that the amountmat variable is decreased by 1 at the end of each iteration of the while loop so that the loop will eventually stop according to how many items the user wants to order.
  2. Run all the cells and then test the function using this table:
Material Amount Distance
“Steel” 4 90
“Cement” 1 90
"Lumber" 6 90
"Glass" 2 90

Your total should come out to be $5574

Turning in/Rubric

REMINDER - For this class, you will only turn in the links to your colab notebooks. You will get a 0 for this assignment if you turn in a python file or a link that is not correct, wrong assignment, or does not give editor permission.

Rubric:

Item Amount
The dictionary is properly created 2
The first for loop is defined correctly 4
The while loop is defined correctly 4
The input statements and related variables are created properly 4
The "cost" variable is pulled from dictionary correctly 4
The total is calculated correctly 6
The function prints every material and its related price 4
The total is returned 2
Total
 30

The following is not a part of the rubric, but specifies how you can lose points. For example: if you do not explain your code when using AI to help you create it or fail to share your link correctly.

Reasons for Points Lost Amount
Link shared incorrectly -10%
Turned in late (per week) -10% (up to -50%)
No comments explaining where AI is used and what its provided code does -50%