In Day 1, we performed basic calculations. Now, we’ll learn how to store data in variables and use Python’s built-in functions to analyze it.
A variable is a labeled container for information. Instead of using a raw number like 500000, we can store it in a variable called revenue, making our code more readable and manageable.
revenue = 500000
quarterly_sales is better than qs.cost_of_goods_sold.Python includes pre-built functions for common tasks:
len(): Finds the length (e.g., number of items in a list).sum(): Calculates the sum of numbers in a list.min() and max(): Find the minimum and maximum values.round(): Rounds a number to a specified number of decimal places.Before you begin, ensure you have followed the setup instructions in the main README.md to set up your virtual environment and install the required libraries.
The script for this lesson, variables.py, has been refactored into functions to promote code reuse and testability.
Day_02_Variables_Builtin_Functions/variables.py. Notice how the logic is now organized into functions like display_company_profile() and analyze_weekly_sales().Coding-For-MBA), run the script:
python Day_02_Variables_Builtin_Functions/variables.py
You will see the output from the example scenarios defined at the bottom of the script.
pytest tests/test_day_02.py
Company Profile Variables:
my_solutions_02.py), declare variables for a fictional company: company_name, year_founded, current_revenue, and is_publicly_traded.Sales Analysis:
[150.50, 200.00, 75.25, 300.75, 120.00].weekly_sales.len()).sum()).min(), max()).Profit Calculator Function:
calculate_profit(revenue, expenses) that takes two numbers and returns the difference.calculate_profit(50000, 35000)) and print the result.🎉 Well done! You’ve learned how to store data in variables and use Python’s built-in functions for analysis—foundational skills for everything that comes next.
Run this lesson’s code interactively in your browser:
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???+ example “solutions.py” View on GitHub
```python title="solutions.py"
"""
Day 2: Solutions to Exercises
"""
# --- Exercise 1: Company Profile Variables ---
print("--- Solution to Exercise 1 ---")
company_name = "InnovateCorp"
year_founded = 2015
current_revenue = 2500000.50
is_publicly_traded = False
print(f"Company Name: {company_name}")
print(f"Year Founded: {year_founded}")
print(f"Current Revenue: ${current_revenue}")
print(f"Is Publicly Traded: {is_publicly_traded}")
print("-" * 20)
# --- Exercise 2: Sales Analysis ---
print("--- Solution to Exercise 2 ---")
weekly_sales = [150.50, 200.00, 75.25, 300.75, 120.00]
print(f"Sales data: {weekly_sales}")
# The total number of sales transactions
num_transactions = len(weekly_sales)
print(f"Total number of transactions: {num_transactions}")
# The total revenue for the week
total_revenue = sum(weekly_sales)
print(f"Total revenue: ${total_revenue:.2f}")
# The smallest sale
min_sale = min(weekly_sales)
print(f"Smallest sale: ${min_sale:.2f}")
# The largest sale
max_sale = max(weekly_sales)
print(f"Largest sale: ${max_sale:.2f}")
# The average sale amount
average_sale = total_revenue / num_transactions
print(f"Average sale amount: ${average_sale:.2f}")
print("-" * 20)
# --- Exercise 3: User Input for a Profit Calculator ---
print("--- Solution to Exercise 3 ---")
# Note: To run this interactively, you would run the python file
# in your terminal. The input() function will pause the script
# and wait for you to type a value and press Enter.
# We wrap the code in a try...except block to handle cases where the user
# might enter text instead of a number, which would cause a crash.
try:
# float() converts the string from input() into a floating-point number
revenue_input = float(input("Enter total revenue: "))
expenses_input = float(input("Enter total expenses: "))
profit = revenue_input - expenses_input
print(f"Calculated Profit: ${profit:.2f}")
except ValueError:
print("Invalid input. Please make sure to enter numbers only.")
print("-" * 20)
```
???+ example “variables.py” View on GitHub
```python title="variables.py"
"""
Day 2: Storing and Analyzing Business Data (Refactored)
This script demonstrates the use of variables to store business data
and built-in functions to perform basic analysis. This version is
refactored into functions for better organization and testability.
"""
def display_company_profile(name, founded, revenue, is_public):
"""Displays the company's profile information."""
print("--- Company Profile ---")
print(f"Company Name: {name}")
print(f"Year Founded: {founded}")
print(f"Current Revenue: ${revenue}")
print(f"Is Publicly Traded: {is_public}")
print("-" * 20)
def analyze_weekly_sales(sales_data):
"""Analyzes and prints a summary of weekly sales data."""
if not sales_data:
print("No sales data to analyze.")
return
print("--- Weekly Sales Analysis ---")
num_transactions = len(sales_data)
total_revenue = sum(sales_data)
smallest_sale = min(sales_data)
largest_sale = max(sales_data)
average_sale = total_revenue / num_transactions if num_transactions > 0 else 0
print(f"Number of Transactions: {num_transactions}")
print(f"Total Weekly Revenue: ${total_revenue:.2f}")
print(f"Smallest Sale: ${smallest_sale:.2f}")
print(f"Largest Sale: ${largest_sale:.2f}")
print(f"Average Sale Amount: ${round(average_sale, 2)}")
print("-" * 20)
return {
"num_transactions": num_transactions,
"total_revenue": total_revenue,
"smallest_sale": smallest_sale,
"largest_sale": largest_sale,
"average_sale": average_sale,
}
def interactive_profit_calculator():
"""Handles user input to calculate and display profit."""
print("--- Interactive Profit Calculator ---")
try:
user_revenue = float(input("Enter your total revenue: "))
user_expenses = float(input("Enter your total expenses: "))
profit = user_revenue - user_expenses
print(f"Your calculated profit is: ${profit:.2f}")
return profit
except ValueError:
print("Invalid input. Please enter numbers only.")
return None
if __name__ == "__main__":
# --- Storing Company Profile in Variables ---
display_company_profile("InnovateCorp", 2015, 2500000.50, False)
# --- Using Built-in Functions for Sales Analysis ---
weekly_sales_data = [150.50, 200.00, 75.25, 300.75, 120.00, 450.50, 275.00]
analyze_weekly_sales(weekly_sales_data)
# --- Getting User Input ---
# Note: This part is not easily testable in an automated way without mocking input.
# The function is separated to keep the core logic testable.
# interactive_profit_calculator() # Uncomment to run the interactive part
```