Check if a Number or String is Symmetrical

Convert Minutes into Seconds

Learn how to convert minutes into seconds in Python using arithmetic multiplication and basic unit conversions.

1. The Challenge: Palindrome Verification

Create a function is_symmetrical(num) that takes a number and returns True if the number is symmetrical (a palindrome that reads the same backward as forward), and False otherwise.

2. Why It Matters

Palindrome checks test string conversion, sequence comparison, and numerical data manipulation.

3. The Python Solution

Convert the number to a string using str(), then compare it to its reversed slice s[::-1]:

def is_symmetrical(num):
    s = str(num)
    return s == s[::-1]

# Testing our function
print(is_symmetrical(7227))   # Output: True
print(is_symmetrical(12567))  # Output: False
print(is_symmetrical(444444)) # Output: True
print(is_symmetrical(9939))   # Output: False

4. Step-by-Step Execution

1. str(7227) yields string "7227".
2. "7227"[::-1] yields reversed string "7227".
3. "7227" == "7227" evaluates to True.

5. Common Mistakes

• Comparing Numbers Without Casting: Trying to reverse an integer directly (num[::-1]) raises a TypeError: 'int' object is not subscriptable. Always convert numbers to strings with str(num) first!

6. Next Steps

Cast numbers to strings before slicing. Next, let's check if a Python dictionary is empty!