In this tutorial we will learn about the python list() method and its uses with examples.
What is the Python list() Method?
The python list() method is used to create a list along with typecasting of the list.
A list is a python built-in data structure that is a collection of ordered and mutable objects. You can learn more about python lists from here(Link).
The syntax of python list() is:
list(iterable)
Python list() Parameters
The list() method takes only one parameter as argument:
- iterable (optional) – an iterable object that can be a sequence or collection of objects. (that can include string, tuples, set, or dictionary)
Example 1: How to use the list() method in python?
# 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’]
Example 2: How to convert a dictionary to list using list() method?
# number list
fruits = {1 : ‘banana’,2 : ‘mango’,3 : ‘apple’}
print(fruits)
fruits_list = list(fruits)
print(fruits_list)
Output:
{1: ‘banana’, 2: ‘mango’, 3: ‘apple’}
[1, 2, 3]
When we try to convert a dictionary to a list, only keys will be the elements of the list. It will not take values in the list. Also, the order of the elements will be random.
Example 3: How to create an empty list in python?
#Empty List
lst = list()
print(lst)
#Check Type of Python
print(type(lst))
Output:
[]
<class ‘list’=“”></class>
Rules of list() method
- If the list() method is passed without a parameter it will return an empty list.
- Dictionary object will only return keys when passed in the list() method.
- Only sequences or collections of objects can be used with the list() method.