Python Lists

Python list used to store the collection of data in a single variable, then there are four ways to store the data in python programming one of them is Python Lists. In python programming we can create a list using the square brackets []. We can place any number of value in list


There are four collection data types in the Python programming language

  • List
  • Tuple
  • Set
  • Dictionary

Python Lists are the collection of data that is ordered and changeable and allows duplicate members.
A tuple is a collection that is ordered and unchangeable and Allows duplicate members.
Python Sets is a collection that is unordered and unindexed and doesn’t allow duplicate members.
Dictionary is a collection which is unordered, changeable and indexed and doesn’t allow duplicate members.

In this tutorial, we are going to learn about printing the elements of a list, modifying elements, deleting elements of the list, and perform many other functions like sum(), len(), max(), min() and many more.’


Python Lists

Python Lists are the collection of the data. Each element of the list has a specific order. We can access each list element by the index number. The first element of the list has a base index i.e. 0.


Syntax of Python List

In Python programming, list elements are written within the square brackets such as:

list_name=[]


Printing a List

Printing a list is simple like printing variables. With the help of one print statement, we can print the list.

Example of printing a List

my_list = ["PHP", "Python", "Java"]
print(my_list)
Tutorials Class - Output Window

[‘PHP’, ‘Python’, ‘Java’]


Topics to remember about Python List

Now, we are going to perform different operations on the list one by one. Don’t forget to see the example provided

Printing a specific element from the list

As of now, we have studied that the list elements are indexed. S. it’s easy to print the specific element of the list by specifying it’s index number.

Example of printing a specific element from the list

my_list = ["PHP", "Python", "Java"]
print(my_list[1])
Tutorials Class - Output Window

Python


Printing elements in between some range from the list

Just like printing specific elements, we can also print the elements within some range as well.

Example of printing list in between some range

my_list = ['T', 'u', 't', 'o', 'r', 'i', 'a', 'l', 's', 'C', 'l', 'a', 's', 's']
# elements 4th to 8th
print(my_list[3:8])
Tutorials Class - Output Window

[‘o’, ‘r’, ‘i’, ‘a’, ‘l’]


Modifying elements of a list

Above we have studied that the list is changeable. So, it’s easy to modify the list elements.

Example of updating a element in list

my_list = ["PHP", "Python", "java"]
my_list[0] = "JavaScript"
print(my_list)
Tutorials Class - Output Window

[‘JavaScript’, ‘Python’, ‘java’]


Checking length of the list

With the help of len() function, we can check the length of the string.

Example to calculate the length of a list

my_list = ['T', 'u', 't', 'o', 'r', 'i', 'a', 'l', 's', 'C', 'l', 'a', 's', 's']
print(len(my_list))
Tutorials Class - Output Window

14

Python Lists – Adding elements

We can easily add an element to the list by using append() function.

Example to adding a element at end of list

my_list = ["apple", "banana", "cherry"]
my_list.append("orange")
print(my_list)
Tutorials Class - Output Window

[‘apple’, ‘banana’, ‘cherry’, ‘orange’]

Adding an element to the specific position


By using insert() function, we can add an element at any specific position by specifying it’s index to the list.

Example to add a element at specific position in list

thislist = ["apple", "banana", "cherry"]
thislist.insert(1, "orange")
print(thislist)
Tutorials Class - Output Window

[‘apple’, ‘orange’, ‘banana’, ‘cherry’]

Adding multiple elements to the list


With the help of the extend() function, we can add multiple elements at the end of the list.

Example to add multiple elements to list

my_list = ["apple", "banana", "cherry"]
my_list.extend(["1kg", "2 dozen", "500g"])
print(my_list)
Tutorials Class - Output Window

[‘apple’, ‘banana’, ‘cherry’, ‘1kg’, ‘2 dozen’, ‘500g’]


Python Lists – Removing specific elements

We can remove any number of elements from the list by specifying it’s value.

Example to remove a specific element by specifying it’s value.

my_list = ["apple", "banana", "cherry"]
my_list.remove("banana")
print(my_list)
Tutorials Class - Output Window

[‘apple’, ‘cherry’]


By specifying it’s index number


We can also remove element from the list by specifying it’s index number.

Example to remove element by specifying its index number

my_list = ["apple", "banana", "cherry"]
del my_list[0]
print(my_list)
Tutorials Class - Output Window

[‘banana’, ‘cherry’]


Python Lists – Making the whole list empty

We can also remove all the elements from the list by using clear() function.

Example to make whole list empty

my_list = ["apple", "banana", "cherry"]
my_list.clear()
print(my_list)
Tutorials Class - Output Window

[]


Python Lists – Deleting the list

With the help of del keyword, we can easily delete a list.

Example to delete a list completely

my_list = ["apple", "banana", "cherry"]
del my_list
 

Note: The output is empty because we have deleted the list.


Checking if any item exists in Python Lists

We can easily check if a element is present in the list or not.

Example to check element is exist in list or not

my_list = ["Ramesh", "Suresh", "Rakesh"]
if "Ramesh" in my_list:
  print("Yes, 'Ramesh' is in this list")
else:
   print("No, 'Ramesh' is not in this list")
Tutorials Class - Output Window

Yes, ‘Ramesh’ is in this list


Counting how many times does a specific value exists in Python List

With the help of count() method, we can also count the frequency of a element in a list.

Example to count the number of times does a value exists in a list.

my_list= [1,2,2,1,2,2,1,"Rakesh"]
print(my_list.count(2))
Tutorials Class - Output Window

4

Here you can see, that specific value present 4 times in our list.


Finding the maximum value in the List

We can also find the maximum value in a list by using max() function.

Example to find maximum value in list

my_list= [1,2,2,1,2,3]
print(max(my_list))
Tutorials Class - Output Window

3


Finding the minimum value in the List

With the help if the min() we can also find the minimum value in a list.

Example to find out minimum value in list

my_list= [1,2,2,1,2,3]
print(min(my_list))
Tutorials Class - Output Window

1


Finding the sum of values in the Tuple

We can easily the sum of all the values of a list by using sum() method.

Example to calculate sum of all the values of a list

my_list= [1,2,2,1,2,3]
print(sum(my_tuple))
Tutorials Class - Output Window

11


Finding the average of values in the list

Like the list, we can calculate the average easily.

Example to calculate the average of all list elements

my_list= [1,2,2,1,2,3]
print(sum(my_list)/len(my_list))
Tutorials Class - Output Window

1.8333333333333333


Finding the position of any value in Python List

In the List, we can also check at what position does a specific element exist by using index() function.

Example to find out the position of a element in list

my_list= ["Ramesh","Suresh","Kamlesh"]
print(my_list.index("Suresh"))  # return 1, so the position will be second
Tutorials Class - Output Window

1


Congratulations! Chapter Finished. Learn more about the similar topics:
Exercises & Assignments
No Content Found.
Interview Questions & Answers
No Content Found.