Project: crash-proof calculator

Python · Unit 9: Errors and exceptions

Full plan
Python
Project
2 exercises

The calculator gets what the person typed: text. When dividing, two things can go wrong: it isn't a number (ValueError), or it's 0 (ZeroDivisionError).

A try can have one except for each error. Python uses the first one whose type matches.

try:
    print(8 / float("0"))
except ValueError:
    print("Not a number")
except ZeroDivisionError:
    print("Division by 0")

Prints

Division by 0

Exercises in this lesson

You do them in the app, which checks them on the spot and explains why.

1. Complete the code
Complete it so the calculator handles both zero and text.
2. Write the code
Write divide(a, b). a and b are the texts the person typed, and they may have decimals. Return the result of the division, "Not a number" if either one isn't a number, or "Division by 0" if b is 0.

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