diff --git a/lab_error_handling_end.ipynb b/lab_error_handling_end.ipynb new file mode 100644 index 0000000..ac44e59 --- /dev/null +++ b/lab_error_handling_end.ipynb @@ -0,0 +1,276 @@ +{ + "cells": [ + { + "cell_type": "markdown", + "id": "25d7736c-ba17-4aff-b6bb-66eba20fbf4e", + "metadata": {}, + "source": [ + "# Lab | Error Handling" + ] + }, + { + "cell_type": "markdown", + "id": "bc99b386-7508-47a0-bcdb-d969deaf6c8b", + "metadata": {}, + "source": [ + "## Exercise: Error Handling for Managing Customer Orders\n", + "\n", + "The implementation of your code for managing customer orders assumes that the user will always enter a valid input. \n", + "\n", + "For example, we could modify the `initialize_inventory` function to include error handling.\n", + " - If the user enters an invalid quantity (e.g., a negative value or a non-numeric value), display an error message and ask them to re-enter the quantity for that product.\n", + " - Use a try-except block to handle the error and continue prompting the user until a valid quantity is entered.\n", + "\n", + "```python\n", + "# Step 1: Define the function for initializing the inventory with error handling\n", + "def initialize_inventory(products):\n", + " inventory = {}\n", + " for product in products:\n", + " valid_quantity = False\n", + " while not valid_quantity:\n", + " try:\n", + " quantity = int(input(f\"Enter the quantity of {product}s available: \"))\n", + " if quantity < 0:\n", + " raise ValueError(\"Invalid quantity! Please enter a non-negative value.\")\n", + " valid_quantity = True\n", + " except ValueError as error:\n", + " print(f\"Error: {error}\")\n", + " inventory[product] = quantity\n", + " return inventory\n", + "\n", + "# Or, in another way:\n", + "\n", + "def initialize_inventory(products):\n", + " inventory = {}\n", + " for product in products:\n", + " valid_input = False\n", + " while not valid_input:\n", + " try:\n", + " quantity = int(input(f\"Enter the quantity of {product}s available: \"))\n", + " if quantity >= 0:\n", + " inventory[product] = quantity\n", + " valid_input = True\n", + " else:\n", + " print(\"Quantity cannot be negative. Please enter a valid quantity.\")\n", + " except ValueError:\n", + " print(\"Invalid input. Please enter a valid quantity.\")\n", + " return inventory\n", + "```\n", + "\n", + "Let's enhance your code by implementing error handling to handle invalid inputs.\n", + "\n", + "Follow the steps below to complete the exercise:\n", + "\n", + "2. Modify the `calculate_total_price` function to include error handling.\n", + " - If the user enters an invalid price (e.g., a negative value or a non-numeric value), display an error message and ask them to re-enter the price for that product.\n", + " - Use a try-except block to handle the error and continue prompting the user until a valid price is entered.\n", + "\n", + "3. Modify the `get_customer_orders` function to include error handling.\n", + " - If the user enters an invalid number of orders (e.g., a negative value or a non-numeric value), display an error message and ask them to re-enter the number of orders.\n", + " - If the user enters an invalid product name (e.g., a product name that is not in the inventory), or that doesn't have stock available, display an error message and ask them to re-enter the product name. *Hint: you will need to pass inventory as a parameter*\n", + " - Use a try-except block to handle the error and continue prompting the user until a valid product name is entered.\n", + "\n", + "4. Test your code by running the program and deliberately entering invalid quantities and product names. Make sure the error handling mechanism works as expected.\n" + ] + }, + { + "cell_type": "code", + "execution_count": null, + "id": "6086e47e", + "metadata": {}, + "outputs": [], + "source": [ + "products = ['t-shirt', 'mug', 'hat', 'book', 'keychain']\n" + ] + }, + { + "cell_type": "code", + "execution_count": 1, + "id": "cd20bcf1", + "metadata": {}, + "outputs": [], + "source": [ + "#1\n", + "def initialize_inventory(products):\n", + " \"\"\"\n", + " Initializes the inventory dict with products names as keys\n", + " and quantities as values.\n", + "\n", + " returns: dict --> initialized inventory\n", + " \"\"\"\n", + " inventory = {}\n", + " for product in products:\n", + " valid_input = False\n", + " while not valid_input:\n", + " try:\n", + " product_qt = int(input(f'Enter product quantity for {product}:'))\n", + " if product_qt >= 0:\n", + " inventory[product] = product_qt\n", + " valid_input = True\n", + " else:\n", + " print('quantity must be positive number')\n", + " except ValueError:\n", + " print('Invalid input, enter nr.')\n", + " return inventory\n", + "\n", + "#2\n", + "def get_customer_orders():\n", + " \"\"\"\n", + " Prompt user to input product names for customer orders\n", + " and returns them as a set.\n", + "\n", + " returns: unique orderes product names\n", + " \"\"\"\n", + " nr_orders = 0\n", + " while True:\n", + " try:\n", + " nr_orders = int(input('Enter how many products to order: ').strip())\n", + " if nr_orders > 0:\n", + " break\n", + " else:\n", + " print('Enter non negative nr.')\n", + " except ValueError:\n", + " print('Error. Enter whole number.')\n", + "\n", + " customer_orders = set()\n", + " if nr_orders == 0:\n", + " print('Customer wants to order 0 products.')\n", + " return customer_orders\n", + " print(f'Enter {nr_orders} products name:')\n", + "\n", + " while len(customer_orders) < nr_orders:\n", + " valid_product_slot = False\n", + " while not valid_product_slot:\n", + " order_input = input(f'Enter product name #{len(customer_orders) + 1}: ').strip()\n", + " if order_input.lower() == 'done':\n", + " if not customer_orders and nr_orders > 0:\n", + " print('No product choose. Exiting order')\n", + " else:\n", + " print('Finishing order input.')\n", + " return customer_orders\n", + " if not order_input:\n", + " print(\"Error. Please enter product name or 'done'\")\n", + " continue\n", + "\n", + " if order_input in inventory:\n", + " if inventory[order_input] > 0:\n", + " if order_input not in customer_orders:\n", + " customer_orders.add(order_input)\n", + " valid_product_slot = True\n", + " else:\n", + " print(f'{order_input} already added to order')\n", + " else:\n", + " print(f'Error: {order_input} out of stock. Choose another.')\n", + " else:\n", + " print(f'Error: {order_input}not found.')\n", + " \n", + " return customer_orders\n", + "\n", + "\n", + "#3\n", + "def update_inventory(customer_orders, inventory):\n", + " \"\"\"\n", + " Updates inventory dict based on customer orders.\n", + " Reduces prodect quantity for each ordered product if available\n", + "\n", + " returns: None\n", + " \"\"\"\n", + " for order_item in customer_orders:\n", + " if order_item in inventory:\n", + " if inventory[order_item] > 0:\n", + " inventory[order_item] -= 1\n", + " print(f\"{order_item}. New quantity: {inventory[order_item]}\")\n", + " else:\n", + " print(f\"'{order_item}' is out of stock.\")\n", + " else:\n", + " print(f\"'{order_item}' not found in inventory.\")\n", + "\n", + "#4\n", + "def calculate_order_statistics(customer_orders, products):\n", + " \"\"\"\n", + " Calculates statistics based on customer orders\n", + " - Total nr. of unique products ordered\n", + " - Percentage of unique products ordered compared to available products\n", + " \n", + " returns: tuple (total_ordered, percentage_ordered)\n", + " \"\"\"\n", + " total_ordered = len(customer_orders)\n", + " total_available = len(products)\n", + " percentage_ordered = (total_ordered / total_available) * 100\n", + "\n", + " return (total_ordered, percentage_ordered)\n", + "\n", + "#5\n", + "def print_order_statistics(order_statistics):\n", + " \"\"\"\n", + " Prints the statistics calculated\n", + " \"\"\"\n", + " total_ordered, percentage_ordered = order_statistics\n", + " print('Order Statistics:')\n", + " print(f'Total Products Ordered: {total_ordered}')\n", + " print(f'Percentage of Products Ordered: {percentage_ordered:.2f}%')\n", + "\n", + "#6\n", + "def print_updated_inventory(inventory):\n", + " if inventory:\n", + " for product, quantity in inventory.items():\n", + " print(f'{product}: {quantity}')\n", + " else:\n", + " print('Inventory is empty.')\n", + " \n", + "def total_price_order(customer_orders):\n", + " \"\"\"\n", + " Calculates de total price of the order. Prompts user to enter price\n", + " of each product and summs the them.\n", + " Assume 1 unit of each\n", + "\n", + " returns: total price of order --> float\n", + " \"\"\"\n", + " product_prices = []\n", + " if customer_orders:\n", + " for product in customer_orders:\n", + " valid_price = False\n", + " while not valid_price:\n", + " try:\n", + " price = float(input(f'Enter price for {product}: €'))\n", + " if price >= 0:\n", + " product_prices.append(price)\n", + " valid_price = True\n", + " else:\n", + " print('Invalid. Price must be positive.')\n", + " except ValueError:\n", + " print('Invalid. Enter price must be numerical.')\n", + " else:\n", + " print('No product to price')\n", + " \n", + " total_price = sum(price for price in product_prices)\n", + " print(f'Total price: {total_price}')\n", + "\n", + " return total_price\n", + "\n", + "\n" + ] + } + ], + "metadata": { + "kernelspec": { + "display_name": "Python 3", + "language": "python", + "name": "python3" + }, + "language_info": { + "codemirror_mode": { + "name": "ipython", + "version": 3 + }, + "file_extension": ".py", + "mimetype": "text/x-python", + "name": "python", + "nbconvert_exporter": "python", + "pygments_lexer": "ipython3", + "version": "3.13.3" + } + }, + "nbformat": 4, + "nbformat_minor": 5 +}