The Python all() function returns true if all the elements of a given iterable (List, Dictionary, Tuple, set, etc.) are True otherwise it returns False. It also returns True if the iterable object is empty. Sometimes while working on some code if we want to ensure that user has not entered a False value then we use the all() function.
Python all() Function in Python
Syntax: all( iterable )
- Iterable: It is an iterable object such as a dictionary,tuple,list,set,etc.
Returns: boolean
Python all() Function with Example
Python3
print(all([True, True, False])) |
Output:
False
Example 1: Working of all() with Lists
Here we are considering list as a iterable.
Python3
# All elements of list are truel = [4, 5, 1]print(all(l))# All elements of list are falsel = [0, 0, False]print(all(l))# Some elements of list are# true while others are falsel = [1, 0, 6, 7, False]print(all(l))# Empty Listl = []print(all(l))# all() with condition - to check if all elements are greater than 0l = [1,-3,0,2,4]print(all(ele > 0 for ele in l)) |
Output
True False False True False
Example 2: Working of all() with Tuples
Here we are considering a tuple as a iterable.
Python3
# All elements of tuple are truet = (2, 4, 6)print(all(t))# All elements of tuple are falset = (0, False, False)print(all(t))# Some elements of tuple# are true while others are falset = (5, 0, 3, 1, False)print(all(t))# Empty tuplet = ()print(all(t))# all() with condition - to check if all elements are evenl = (2,4,6,8,10)print(all(ele % 2 == 0 for ele in l)) |
Output
True False False True True
Example 3: Working of all() with Sets
Here sets are referred to as iterables
Python3
# All elements of set are trues = {1, 1, 3}print(all(s))# All elements of set are falses = {0, 0, False}print(all(s))# Some elements of set# are true while others are falses = {1, 2, 0, 8, False}print(all(s))# Empty sets = {}print(all(s))# all() with condition - to check if absolute of all elements is greater than 2l = {-4,-3,6,-5,4}print(all(abs(ele) > 2 for ele in l)) |
Output
True False False True True
Example 4: Working of all() with Dictionaries
Here we are considering dictionaries as iterables.
Python3
# All elements of dictionary are trued = {1: "Hello", 2: "Hi"}print(all(d))# All elements of dictionary are falsed = {0: "Hello", False: "Hi"}print(all(d))# Some elements of dictionary# are true while others are falsed = {0: "Salut", 1: "Hello", 2: "Hi"}print(all(d))# Empty dictionaryd = {}print(all(d))# all() with condition - to check if all letters of word 'time' are therel = {"t":1, "i":1, "m":2, "e":0}print(all(ele > 0 for ele in l.values())) |
Output
True False False True False
Note: In the case of a dictionary if all the keys of the dictionary are true or the dictionary is empty the all() returns True, else it returns False.
Example 5: Working of all() with Strings
Python3
# Non-Empty Strings = "Hi There!"print(all(s))# Non-Empty Strings = "000"print(all(s))# Empty strings = ""print(all(s)) |
Output
True True True
