How Can I Reliably Determine if a String Input Represents a Number in Python?

Determining the Numeric Nature of String Input

In Python, a user's string input may often resemble a number, leaving you wondering if it actually represents one. Here's how to determine the true nature of such input:

The code snippet below attempts to check if the user's input is a number using a type check:

user_input = input("Enter something:")

if type(user_input) == int:
    print("Is a number")
else:
    print("Not a number")

However, this approach fails because input always returns a string, regardless of the user's input.

To accurately ascertain the numeric nature of the input, we employ a more robust method:

try:
    val = int(userInput)
except ValueError:
    print("That's not an int!")

Using a try-except block, we attempt to convert the user's input to an integer. If the conversion succeeds, it's treated as a number, but if a ValueError occurs, indicating an invalid integer, an appropriate error message is displayed.

This approach allows you to gracefully handle non-numeric inputs, providing a more robust and informative handling mechanism.

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