The list() function helps to returns a list object in Python. List in python are ordered and have a precise count. The list components are indexed and therefore the index starts with zero.
list([iterable]) # object can be string,sets,tuples,dictionary etc
Takes only one parameter. In this the sequence can be strings, tuples and collection can be set, dictionary.
| Parameter | Description | Required / Optional |
|---|---|---|
| iterable | an object that could be a sequence or collection or any iterator object | Optional |
It returns a list and has only one parameter.
| Input | Return Value |
|---|---|
| no parameters | empty list |
| iterable is passed | a list consisting of iterable's items |
# empty list
print(list())
# vowel string
vowel_string = 'aeiou'
print(list(vowel_string))
# vowel tuple
vowel_tuple = ('a', 'e', 'i', 'o', 'u')
print(list(vowel_tuple))
# vowel list
vowel_list = ['a', 'e', 'i', 'o', 'u']
print(list(vowel_list))
Output:
[] ['a', 'e', 'i', 'o', 'u'] ['a', 'e', 'i', 'o', 'u'] ['a', 'e', 'i', 'o', 'u']
# vowel set
vowel_set = {'a', 'e', 'i', 'o', 'u'}
print(list(vowel_set))
# vowel dictionary vowel_dicti 1, 'e': 2, 'i': 3, 'o':4, 'u':5}
print(list(vowel_dictionary))
Output:
['a', 'o', 'u', 'e', 'i'] ['o', 'e', 'a', 'u', 'i']
# objects of this class are iterators
class PowTwo:
def __init__(self, max):
self.max = max
def __iter__(self):
self.num = 0
return self
def __next__(self):
if(self.num >= self.max):
raise StopIteration
result = 2 ** self.num
self.num += 1
return result
pow_two = PowTwo(5)
pow_two_iter = iter(pow_two)
print(list(pow_two_iter))
Output:
[1, 2, 4, 8, 16]
