python-fefedfasdgsgfahfdshdhunctions-190506123237.pptx
- 1. Python Functions, class & object, Error Handling
- 2. Functions Piece of reusable code Solves particular task Call function instead of writing code yourself Built-in function User defined function Type of function:
- 3. Built-in Functions Syntax of Function print(): Outputs data to the console.
- 4. Function Call Once we have defined a function, we can call it from another function, program or even the Python prompt. To call a function we simply type the function name with appropriate parameters. Calling the Function my_function()
- 5. Square Function:Take one arguments and prints its square
- 6. Scope and Lifetime of variables Scope of a variable is the portion of a program where the variable is recognized. Parameters and variables defined inside a function is not visible from outside. Hence, they have a local scope. Lifetime of a variable is the period throughout which the variable exits in the memory. The lifetime of variables inside a function is as long as the function executes. They are destroyed once we return from the function. Hence, a function does not remember the value of a variable from its previous calls.
- 9. Global Scope
- 10. Default Arguments In this function, the parameter amount does not have a default value and is required (mandatory) during a call. On the other hand, the parameter discountPercentage has a default value of 0. So, it is optional during a call. If a value is provided, it will overwrite the default value. Any number of arguments in a function can have a default value.
- 11. Default Arguments Once we have a default argument, all the arguments to its right must also have default values. Syntax-Error : non-default argument follows default argument
- 12. Default Arguments Function arguments can have default values in Python. We can provide a default value to an argument by using the assignment operator (=).
- 13. Variable number of arguments *a allows the function to accept any number of positional arguments as a tuple.
- 14. Functions as Objects ● Although functions are created differently from normal variables, functions are just like any other kind of value. ● They can be assigned and reassigned to variables, and later referenced by those names.
- 15. Python OOPs Concepts Like other general-purpose programming languages, Python is also an object-oriented language since its beginning. It allows us to develop applications using an Object-Oriented approach. In Python, we can easily create and use classes and objects. An object-oriented paradigm is to design the program using classes and objects. The object is related to real-word entities such as book, house, pencil, etc.
- 16. Class: The class can be defined as a collection of objects. It is a logical entity that has some specific attributes and methods. For example: if you have an employee class, then it should contain an attribute and method, i.e. an email id, name, age, salary, etc. Syntax: class ClassName: <statement-1> . . <statement-N>
- 17. Object: The object is an entity that has state and behavior. It may be any real-world object like the mouse, keyboard, chair, table, pen, etc. Everything in Python is an object, and almost everything has attributes and methods. All functions have a built-in attribute __doc__, which returns the docstring defined in the function source code. When we define a class, it needs to create an object to allocate the memory. Consider the following class car: def __init__(self,modelname, year): self.modelname = modelname self.year = year def display(self): print(self.modelname,self.year) example.
- 18. Python Exception Handling- Error in Python can be of two types i.e. Syntax errors and Exceptions. Errors are problems in a program due to which the program will stop the execution. On the other hand, exceptions are raised when some internal events occur which change the normal flow of the program. Difference between Syntax Error and Exceptions Syntax Error: As the name suggests this error is caused by the wrong syntax in the code. It leads to the termination of the program. amount = 10000 if(amount > 2999) print("You are eligible to purchase Dsa Self Paced")
- 19. Python Exception Handling- Exceptions: Exceptions are raised when the program is syntactically correct, but the code results in an error. This error does not stop the execution of the program, however, it changes the normal flow of the program. Example:- Here in this code as we are dividing the ‘marks’ by zero so a error will occur known as ‘ZeroDivisionError’. ‘ZeroDivisionError’ occurs when we try to divide any number by 0. marks = 10000 a = marks / 0 print(a)
- 20. Python Exception Handling- Example:- TypeError: This exception is raised when an operation or function is applied to an object of the wrong type. Here’s an example: x = 5 y = "hello" z = x + y
Editor's Notes
- #2: Function is a group of related statements that perform a specific task. Functions help break our program into smaller and modular chunks. As our program grows larger and larger, functions make it more organized and manageable. Furthermore, it avoids repetition and makes code reusable.
- #6: def my_func(): x = 10 print("Value inside function:",x) x = 20 my_func() print("Value outside function:",x)
- #9: total = 0 def add(a , b): global total total = a + b print('Inside add total = ', total) add(4, 9) print('Main Block total = ', total)
- #12: def calculateTotal(amount , discountPercentage = 0): discountAmount = discountPercentage / 100 * amount return amount - discountAmount amount = 500 totalBillAmount = calculateTotal(amount , 10) print(totalBillAmount) amount = 500 totalBillAmount = calculateTotal(amount) print(totalBillAmount) 450 500
- #13: def mysum(*a): total = 0 for ele in a: print(total,"+",ele,"=", end='') total += ele print(total) return total print(mysum(5, 2, 9, 4)) ------------------------------------- Built-in sum function works with list (not variable number of arguments) Max function works with variable number of arguments --------------------------------------------------------------- def mymax(a,*b): large = a for ele in b: if ele > large: large = ele return large print(mymax(4,5,7,3,1,8,2))
- #14: def multiply(x, y): return x * y a = 4 b = 7 operation = multiply print(operation(a, b))
- #15: def multiply(x, y): return x * y a = 4 b = 7 operation = multiply print(operation(a, b))
- #16: def multiply(x, y): return x * y a = 4 b = 7 operation = multiply print(operation(a, b))
- #17: def multiply(x, y): return x * y a = 4 b = 7 operation = multiply print(operation(a, b))
- #18: def multiply(x, y): return x * y a = 4 b = 7 operation = multiply print(operation(a, b))
- #19: def multiply(x, y): return x * y a = 4 b = 7 operation = multiply print(operation(a, b))
- #20: def multiply(x, y): return x * y a = 4 b = 7 operation = multiply print(operation(a, b))