all() Function in Python

Python all() Function

The all() function in Python is a built-in function that takes an iterable (such as a list, tuple, or set) as an argument and returns True if all the elements in the iterable are evaluated as True. If the iterable contains any elements that are evaluated as False, 0, None, or an empty string, the all() function will return False.

Here's the syntax of the all() function:

all(iterable)

The iterable argument can be any iterable object, such as a list, tuple, set, or even a string. The all() function will iterate over the elements of the iterable and check if all the elements are evaluated as True. If all elements are True, it will return True; otherwise, it will return False.

Here are a few examples to illustrate the usage of the all() function:

Example 1:

numbers = [2, 4, 6, 8, 10]
result = all(num % 2 == 0 for num in numbers)
print(result)  # Output: True

In this example, the all() function checks if all the numbers in the list are even. Since all the numbers satisfy the condition num % 2 == 0, the all() function returns True.

Example 2:

fruits = ['apple', 'banana', 'cherry', '']
result = all(fruit for fruit in fruits)
print(result)  # Output: False

In this example, the all() function checks if all the elements in the list of fruits are non-empty strings. Since the empty string '' evaluates as False, the all() function returns False.

Example 3:

numbers = [3, 5, 7, 9, 11]
result = all(num % 2 == 0 for num in numbers)
print(result)  # Output: False

In this example, the all() function checks if all the numbers in the list are even. Since none of the numbers satisfy the condition num % 2 == 0, the all() function returns False.

Note that if the iterable passed to the all() function is empty, it will return True because there are no elements that evaluate to False.