Python Program to remove a specific digit from every element of the list

When you need to remove a specific digit from every element of a list, you can use string manipulation with list comprehension and filtering techniques.

Example

Below is a demonstration of removing digit 3 from all list elements ?

numbers = [123, 565, 1948, 334, 4598]

print("The list is:")
print(numbers)

digit_to_remove = 3
print("The digit to remove is:")
print(digit_to_remove)

result = []

for element in numbers:
    # Convert to string and filter out the specific digit
    filtered_digits = ''.join([digit for digit in str(element) if int(digit) != digit_to_remove])
    
    # If all digits were removed, append empty string or 0
    if filtered_digits == '':
        result.append('')
    else:
        result.append(int(filtered_digits))

print("The result is:")
print(result)

The list is:
[123, 565, 1948, 334, 4598]
The digit to remove is:
3
The result is:
[12, 565, 1948, 4, 4598]

Using List Comprehension

A more concise approach using list comprehension ?

numbers = [123, 565, 1948, 334, 4598]
digit_to_remove = 3

result = [
    int(''.join([d for d in str(num) if int(d) != digit_to_remove])) 
    if ''.join([d for d in str(num) if int(d) != digit_to_remove]) != '' 
    else 0
    for num in numbers
]

print("Original list:", numbers)
print("After removing digit", digit_to_remove, ":", result)

Original list: [123, 565, 1948, 334, 4598]
After removing digit 3 : [12, 565, 1948, 4, 4598]

Handling Edge Cases

When all digits in a number are the target digit (like 333), you need to handle this case ?

numbers = [123, 333, 1948, 334, 4598]
digit_to_remove = 3

result = []
for num in numbers:
    # Remove the target digit
    filtered = ''.join([d for d in str(num) if int(d) != digit_to_remove])
    
    # Handle case where all digits were removed
    if filtered == '':
        result.append(0)  # or use None, or skip entirely
    else:
        result.append(int(filtered))

print("Original:", numbers)
print("Result:  ", result)

Original: [123, 333, 1948, 334, 4598]
Result:   [12, 0, 1948, 4, 4598]

How It Works

• String conversion: Convert each number to string to access individual digits
• Filtering: Use list comprehension to keep only digits that don't match the target
• Rejoining: Join filtered digits back into a string
• Type conversion: Convert back to integer if result is not empty

Conclusion

Use string manipulation with list comprehension to remove specific digits from numbers. Handle edge cases where all digits are removed by returning 0 or an appropriate default value.