Tutorial Playlist
200 Lessons1. Introduction to Python
2. Features of Python
3. How to install python in windows
4. How to Install Python on macOS
5. Install Python on Linux
6. Hello World Program in Python
7. Python Variables
8. Global Variable in Python
9. Python Keywords and Identifiers
10. Assert Keyword in Python
11. Comments in Python
12. Escape Sequence in Python
13. Print In Python
14. Python-if-else-statement
15. Python for Loop
16. Nested for loop in Python
17. While Loop in Python
18. Python’s do-while Loop
19. Break in Python
20. Break Pass and Continue Statement in Python
21. Python Try Except
22. Data Types in Python
23. Float in Python
24. String Methods Python
25. List in Python
26. List Methods in Python
27. Tuples in Python
28. Dictionary in Python
29. Set in Python
30. Operators in Python
31. Boolean Operators in Python
32. Arithmetic Operators in Python
33. Assignment Operator in Python
34. Bitwise operators in Python
35. Identity Operator in Python
36. Operator Precedence in Python
37. Functions in Python
38. Lambda and Anonymous Function in Python
39. Range Function in Python
40. len() Function in Python
41. How to Use Lambda Functions in Python?
42. Random Function in Python
43. Python __init__() Function
44. String Split function in Python
45. Round function in Python
46. Find Function in Python
47. How to Call a Function in Python?
48. Python Functions Scope
49. Method Overloading in Python
50. Method Overriding in Python
51. Static Method in Python
52. Python List Index Method
53. Python Modules
54. Math Module in Python
55. Module and Package in Python
56. OS module in Python
57. Python Packages
58. OOPs Concepts in Python
59. Class in Python
60. Abstract Class in Python
61. Object in Python
62. Constructor in Python
63. Inheritance in Python
64. Multiple Inheritance in Python
65. Encapsulation in Python
66. Data Abstraction in Python
67. Opening and closing files in Python
68. How to open JSON file in Python
69. Read CSV Files in Python
70. How to Read a File in Python
71. How to Open a File in Python?
72. Python Write to File
73. JSON Python
74. Python JSON – How to Convert a String to JSON
75. Python JSON Encoding and Decoding
76. Exception Handling in Python
77. Recursion in Python
78. Python Decorators
79. Python Threading
80. Multithreading in Python
81. Multiprocеssing in Python
82. Python Regular Expressions
83. Enumerate() in Python
84. Map in Python
85. Filter in Python
86. Eval in Python
87. Difference Between List, Tuple, Set, and Dictionary in Python
88. List to String in Python
89. Linked List in Python
90. Length of list in Python
91. Reverse a List in Python
92. Python List remove() Method
93. How to Add Elements in a List in Python
94. How to Reverse a List in Python?
95. Difference Between List and Tuple in Python
96. List Slicing in Python
97. Sort in Python
98. Merge Sort in Python
99. Selection Sort in Python
100. Sort Array in Python
101. Sort Dictionary by Value in Python
102. Datetime Python
103. Random Number in Python
104. 2D Array in Python
105. Abs in Python
106. Advantages of Python
107. Anagram Program in Python
108. Append in Python
109. Applications of Python
110. Armstrong Number in Python
111. Assert in Python
112. Binary Search in Python
113. Binary to Decimal in Python
114. Bool in Python
115. Calculator Program in Python
116. chr in Python
117. Control Flow Statements in Python
118. Convert String to Datetime Python
119. Count in python
120. Counter in Python
121. Data Visualization in Python
122. Datetime in Python
123. Extend in Python
124. F-string in Python
125. Fibonacci Series in Python
126. Format in Python
127. GCD of Two Numbers in Python
128. How to Become a Python Developer
129. How to Run Python Program
130. In Which Year Was the Python Language Developed?
131. Indentation in Python
132. Index in Python
133. Interface in Python
134. Is Python Case Sensitive?
135. Isalpha in Python
136. Isinstance() in Python
137. Iterator in Python
138. Join in Python
139. Leap Year Program in Python
140. Lexicographical Order in Python
141. Literals in Python
142. Matplotlib
143. Matrix Multiplication in Python
144. Memory Management in Python
145. Modulus in Python
146. Mutable and Immutable in Python
147. Namespace and Scope in Python
148. OpenCV Python
149. Operator Overloading in Python
150. ord in Python
151. Palindrome in Python
152. Pass in Python
153. Pattern Program in Python
154. Perfect Number in Python
155. Permutation and Combination in Python
156. Prime Number Program in Python
157. Python Arrays
158. Python Automation Projects Ideas
159. Python Frameworks
160. Python Graphical User Interface GUI
161. Python IDE
162. Python input and output
163. Python Installation on Windows
164. Python Object-Oriented Programming
165. Python PIP
166. Python Seaborn
167. Python Slicing
168. type() function in Python
169. Queue in Python
170. Replace in Python
171. Reverse a Number in Python
172. Reverse a string in Python
173. Reverse String in Python
174. Stack in Python
175. scikit-learn
176. Selenium with Python
177. Self in Python
Now Reading
178. Sleep in Python
179. Speech Recognition in Python
180. Split in Python
181. Square Root in Python
182. String Comparison in Python
183. String Formatting in Python
184. String Slicing in Python
185. Strip in Python
186. Subprocess in Python
187. Substring in Python
188. Sum of Digits of a Number in Python
189. Sum of n Natural Numbers in Python
190. Sum of Prime Numbers in Python
191. Switch Case in Python
192. Python Program to Transpose a Matrix
193. Type Casting in Python
194. What are Lists in Python?
195. Ways to Define a Block of Code
196. What is Pygame
197. Why Python is Interpreted Language?
198. XOR in Python
199. Yield in Python
200. Zip in Python
Python, cherished for its approachability and versatility, has captured the hearts of developers worldwide. Yet, amidst its simplicity lies a profound concept that is foundational to object-oriented programming in Python: "self." In this extensive exploration, we'll dive into the Python self type, its pivotal role in creating clean and organized code, and the subtle distinctions that set it apart from other programming languages.
Before we embark on our journey into the intricacies of the self parameter in Python, it's essential to establish a broad understanding. Self in Python is not a mere keyword; it is a practice. It acts as a reference to the instance of a class and a gateway to instance-specific attributes and methods. To truly appreciate the essence of "self," let's journey deeper into its functionality.
Now, what is self in Python? The "self" method stands at the core of Python's object-oriented philosophy. It serves as the conduit through which we access instance-specific attributes and methods. Let's solidify our understanding through practical examples.
Class MyClass:
class MyClass:
def __init__(self, name):
self.name = name
def greet(self):
return f"Hello, I am {self.name}"
obj = MyClass("Alice")
print(obj.greet())
In this illustrative example, we've crafted a class called MyClass. Inside this class, the __init__ method, often called the constructor, welcomes two parameters: "self" and "name." Here, "self" represents the instance of the class, while "name" is a parameter provided during the creation of an object from this class. The __init__ method's mission is to initialize attributes for the instance. In this instance, it assigns the "name" parameter to the instance's self.name attribute.
Furthermore, we've introduced another method, greet, which employs the self.name attribute to create a personalized greeting for the instance. When we build an object obj of MyClass and invoke the greet method, we receive a tailored greeting: "Hello, I am Alice."
Class Person:
def __init__(self, name, age):
self.name = name
self.age = age
defcelebrate_birthday(self):
self.age = 1
Alice = Person("Alice", 30)
Alice.celebrate_birthday()
print(f"{alice.name} is now {alice.age} years old.")
In this extended example, we introduce a class named Person to represent individuals. This class incorporates attributes for "name" and "age." The __init__ method initializes these attributes using the provided parameters. Moreover, we unveil a system named celebrate_birthday. When invoked, this method increments the "age" attribute of the instance by one, simulating a birthday celebration.
Once more, we create an instance of the Person class, christening it as "alice" with an initial age of 30. By invoking the celebrate_birthday method on "alice," we modify the "age" attribute, resulting in the statement: "Alice is now 31 years old."
These examples show the pivotal role played by the "self" parameter, serving as a reference to the instance. It facilitates the manipulation of instance-specific data within methods, embodying the essence of object-oriented programming.
A common question that frequently arises is why the "self" method necessitates explicit definitions within every method of a class. To address this, we must delve into how Python manages method calls within classes and the Python call self function.
In Python, when you call a method on an object, such as obj.method(), Python automatically endows the method with the instance as the first Python self argument. This seamless instance passing is where the "self" parameter becomes invaluable.
Imagine a scenario where Python refrained from this automatic instance provision. In such a scenario, developers would be compelled to pass the instance explicitly every time they called a method. Not only would this be cumbersome, but it would also introduce opportunities for errors.
By mandating the inclusion of the "self" parameter in method signatures, Python ensures a smooth, error-free process for accessing instance-specific data and methods. This practice is not a mere formality; it is an integral aspect of Python's object-oriented nature.
Defining "self" in methods isn't a mere convention; it is a fundamental component of how Python's object-oriented programming paradigm thrives.
The "self" variable, closely related to the "self" parameter, often assumes a pivotal role within methods to access instance-specific attributes and methods. Let's delve even deeper with a practical example.
Example: Harnessing the "Self" Variable
Class Car:
def __init__(self, make, model):
self.make = make
self.model = model
defdescription(self):
return f"This vehicle is a {self.make} {self.model}."
my_car = Car("Toyota", "Camry")
print(my_car.description())
In this illuminating example, we introduce a Car class meticulously designed to represent vehicles. The class boasts an __init__ method that graciously welcomes two parameters: "make" and "model." These parameters find their rightful place within the instance's self.make and self.model attributes, capturing vital information about the car, including its manufacturer and model.
Moreover, the class features a descriptionmethod, which seamlessly harnesses the"self"variable to access the"make"and"model"attributes of the instance. The description method crafts a descriptive string, offering details about the car's make and model.
To illustrate the practical application of this class, we create an instance of a Carnamed"my_car,"specifying that it is none other than a Toyota Camry. When we summon the escription method on"my_car," we are bestowed with the following output: "This vehicle is a Toyota Camry."
The "self" variable assumes the role of a bridge, artfully connecting the instance to its attributes and methods. It simplifies the encapsulation of instance-specific data within the class and plays a pivotal role in crafting well-structured and modular code.
The concept of selfin Python may draw comparisons with the "this" keyword utilized in other programming languages such as Java or C . However, it's paramount to recognize that there exist substantial differences between the two.
Self in Pythonkeyword is not rigid; it is a convention. Developers frequently designate "self" as the first parameter in method definitions, yet it does not hold the status of a reserved keyword in the language. You can select any variable name to represent the instance reference. Nevertheless, the adoption of "self" is encouraged, and it has emerged as a prevalent practice within the Python community due to its clarity and consistency.
Conversely, "this" in languages like Java and C is a dedicated keyword. It explicitly alludes to the current instance of a class. In these languages, "this" serves an indispensable role in distinguishing between instance variables and method parameters that share identical names. Python, with its automatic bestowal of the instance reference, eradicates the necessity for a dedicated keyword like "this." The instance resides within methods without the demand for an explicit reference.
In this section about "self"vs."this" in Python, we discovered that the two share a common goal in object-oriented programming, their implementation and utilization diverge significantly between Python and other programming languages.
In Python, the `__init__` method is commonly referred to as a constructor, but it's important to understand that it's not a true constructor in the traditional sense found in some other programming languages like C++ or Java.
Here's what's happening:
1. Initialization Purpose: The `__init__` method is a special method in Python classes that is automatically called when a new instance of a class is created. It is used to initialize the object's attributes and perform any other necessary setup.
2. Object Initialization: While it's similar to a constructor in the sense that it initializes an object, it doesn't actually construct or allocate memory for the object. That's done by the `__new__` method, which is rarely used directly in Python and usually not needed.
3. Initialization vs Construction: In languages like C++ or Java, constructors are responsible for both memory allocation and initialization of objects. In Python, the allocation of memory is handled behind the scenes by the interpreter. The `__init__` method is purely for object initialization.
4. Separation of Concerns: This separation of concerns in Python is a design choice that allows for greater flexibility and simplicity. It makes it easier to subclass and customize the initialization behavior without having to deal with memory allocation.
5. Initialization Overloading: You can think of the `__init__` method as an initializer rather than a constructor. It allows you to customize the way an instance of a class is set up without worrying about low-level memory management.
6. Other Methods for Custom Initialization: If you need more control over object creation, you can use other methods like `__new__`, but this is relatively rare in standard Python programming and is usually reserved for advanced use cases.
In summary, while `__init__` is commonly referred to as a constructor, it's more accurate to think of it as an initializer. It's responsible for setting up the initial state of an object after memory has been allocated, rather than being responsible for the actual allocation of memory.
In Python, the term "self" is a convention used to represent the instance of a class. It allows you to access and manipulate attributes and methods specific to that instance. In instance methods (functions defined inside a class), the first parameter must always be `self`. This parameter is automatically passed when you call a method on an instance, allowing it to operate on its own attributes. Understanding "self" is crucial for effective object-oriented programming in Python. It enables the creation of classes with attributes and behaviors that can be tailored for each instance, providing a foundation for building complex and dynamic applications.
1. What is the purpose of "self" in Python?
"Self"in Python serves as a reference to the instance of the class. It bestows access to instance-specific attributes and methods, embodying the essence of object-oriented programming.
2. Is "self" a keyword in Python?
No, "self" is not a keyword; it functions as a convention. Employed as a parameter in method definitions, it refers to the instance.
3. What role does the __init__() method play in Python?
The __init__() method serves as an initializer in Python. It initializes attributes and carries out preparatory tasks when an object of a class is formed, although it does not create instances, a process automated by Python.
4. Why must "self" be explicitly defined in Python methods?
An explicit definition of "self" is necessary as Python doesn't automatically pass the instance as the initial parameter to methods. This practice provides developers with greater control.
5. How does "self" in Python compare to "this" in other languages?
"Self" in Python is conceptually similar to "this" in some other programming languages, representing the current instance of a class. However, Python's use of "self" enhances code clarity and readability.
PAVAN VADAPALLI
Director of Engineering
Director of Engineering @ upGrad. Motivated to leverage technology to solve problems. Seasoned leader for startups and fast moving orgs. Working …Read More
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upGrad does not grant credit; credits are granted, accepted or transferred at the sole discretion of the relevant educational institution offering the diploma or degree. We advise you to enquire further regarding the suitability of this program for your academic, professional requirements and job prospects before enr...