Create a tool for math calculations

It's time to build your tool. Let's imagine you run a small construction company and need to calculate the length of one side of a roof. If you know the lengths of two beams that support the roof at a right angle, you can use their lengths to calculate the length of the roof using the hypotenuse formula below. $$c = \sqrt{a^2 + b^2}$$

Roof beam calculation diagram

This exercise is part of the course

Designing Agentic Systems with LangChain

Exercise instructions

Use the necessary decorator to define the function as a tool.
To find the hypotenuse, use the .split() method on the input string to extract the two other lengths of a right-sided triangle.
Convert each triangle side, a and b, to floats and use .strip() to remove any extra spaces from the values.
Use Python's math module to square the lengths a and b, sum their values, and find their square root to reveal the length of the roof.

Hands-on interactive exercise

Have a go at this exercise by completing this sample code.

# Define this math function as a tool
____
def hypotenuse_length(input: str) -> float:
    """Calculates the length of the hypotenuse of a right-angled triangle given the lengths of the other two sides."""
    
    # Split the input string to get the lengths of the triangle
    sides = ____.____(',')
    
    # Convert the input values to floats, removing extra spaces
    a = ____(____[0].____())
    b = ____(____[1].____())
    
    # Square each of the values, add them together, and find the square root 
    return ____.sqrt(a____2 + b____2)

Edit and Run Code

This exercise is part of the course

Designing Agentic Systems with LangChain

IntermediateSkill Level

4.8+

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Build intelligent agentic systems! Discover the key components of LangChain agents, including how prompts, LLMs, and tools work together for reasoning and action. You'll set up an agent with OpenAI's API, define custom tools, and tackle real-world tasks like math calculations. Plus, explore how LangChain organizes data using graphs, nodes, and edges.

Exercise 1: Agents in LangChain Exercise 2: Creating a ReAct agent Exercise 3: Components of LangChain agents Exercise 4: Building custom tools Exercise 5: Create a tool for math calculations

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