Úvod
The Krajta příkaz return se používá k vrácení hodnoty z funkce. Uživatel může ve funkci použít pouze příkaz return. Nelze jej použít mimo funkci Pythonu. Příkaz return obsahuje klíčové slovo return a hodnotu, která bude vrácena poté.
Syntaxe příkazu return:
def funtion_name(): statements . . . return [expression]
Program 1
def adding(x, y): i = x + y return i result = adding(16, 25) print(f'Output of adding(16, 25) function is {result}')
Výstup
Program 2
def adding(a, b): # this function is return the value of (a + b) return a + b def boolean_function(a): # this function is return the Boolean value return bool(a) # calling function flag = adding(2, 3) print('Output of first function is {}'.format(flag)) flag = boolean_function(9 <5) print(' output of second function is {}'.format(flag)) < pre> <p> <strong>Output.</strong> </p> <img src="//techcodeview.com/img/python-tutorial/18/python-return-statement-2.webp" alt="Python return statement"> <h3>Returning Multiple Values</h3> <p>In the Python programming language, a user can return multiple values from a function. The following are the various methods for this.</p> <p> <strong>1. Using Object:</strong> This method is similar to <a href="/c-programming-language-tutorial">C</a> / <a href="/c-tutorial">C ++</a> and <a href="/java-tutorial">Java</a> . A user can create a class to hold multiple values in a function and return an object of that class.</p> <pre> class a: def __init__(self): self.omg = 'javatpoint is the best website to learn' self.i = 122 # This function will return an object of the class a def test(): return a() # Driver code to test the above method z = test() print(z.omg) print(z.i) </pre> <p> <strong>Output</strong> </p> <img src="//techcodeview.com/img/python-tutorial/18/python-return-statement-3.webp" alt="Python return statement"> <p> <strong>2. Using Tuple:</strong> The tuple is similar to a list, but there is a slight difference between tuple and list. In the tuple, the object values cannot be changed, while the object value can be changed in the list.</p> <pre> def test(): omg = 'javatpoint is the best website to learn' i = 122 return omg, i; # Return tuple, we could also. # Driver code to test the above method. omg, i = test() # Assign return tuple print(omg) print(i) </pre> <p> <strong>Output</strong> </p> <img src="//techcodeview.com/img/python-tutorial/18/python-return-statement-4.webp" alt="Python return statement"> <p> <strong>3. Using list:</strong> The list is similar to the dynamically sized array. In the list, the user can store everything in a single variable.</p> <pre> def test(): omg = 'javatpoint' i = 122 return [omg, i]; # Driver code to test the above method list = test() print(list) </pre> <p> <strong>Output</strong> </p> <img src="//techcodeview.com/img/python-tutorial/18/python-return-statement-5.webp" alt="Python return statement"> <p> <strong>4. Using dictionary:</strong> In the Python language, a dictionary is a collection of unstructured items that are used to store data values such as hash or map.</p> <pre> def test(): a = dict(); a['omg'] = 'javatpoint' a['i'] = 122 return a # Driver code to test the above method a = test() print(a) </pre> <p> <strong>Output</strong> </p> <img src="//techcodeview.com/img/python-tutorial/18/python-return-statement-6.webp" alt="Python return statement"> <p> <strong>5. Using Data Class (Python 3.7+)</strong> </p> <pre> from dataclasses import dataclass @dataclass class Book_list: bookname: str cost: float quantity_of_book_available: int = 0 # This function is used to calculate the total cost of the books def total_cost_of_book(self) -> float: return self.cost * self.quantity_of_book_available book = Book_list('Python programming language.', 499, 10) i = book.total_cost_of_book() # print the total cost print(i) # print the details of the book print(book) </pre> <p> <strong>Output</strong> </p> <img src="//techcodeview.com/img/python-tutorial/18/python-return-statement-7.webp" alt="Python return statement"> <h3>Function returning another function</h3> <p>In the Python programming language, a function is in the form of an object. Therefore, the user can return a function from another function.</p> <p>In the below program, The first_add function returns the second_add function.</p> <pre> def first_add(x): def second_add(y): return x + y return second_add i = first_add(20) print('The value of x + y is', i(10)) # second function def outer_func(x): return x * 5 def func(): # return the value in the different function return outer_func # storing the function in z z = func() print(' The value of x * y is', z(10)) </pre> <p> <strong>Output</strong> </p> <img src="//techcodeview.com/img/python-tutorial/18/python-return-statement-8.webp" alt="Python return statement"> <hr></5)>
Výstup
herec chiranjeevi
2. Použití Tuple: N-tice je podobná seznamu, ale mezi n-ticí a seznamem je malý rozdíl. V n-tice nelze změnit hodnoty objektu, zatímco hodnotu objektu lze změnit v seznamu.
def test(): omg = 'javatpoint is the best website to learn' i = 122 return omg, i; # Return tuple, we could also. # Driver code to test the above method. omg, i = test() # Assign return tuple print(omg) print(i)
Výstup
3. Použití seznamu: Seznam je podobný dynamickému poli. V seznamu si uživatel může vše uložit do jediné proměnné.
def test(): omg = 'javatpoint' i = 122 return [omg, i]; # Driver code to test the above method list = test() print(list)
Výstup
4. Použití slovníku: V jazyce Python je slovník sbírka nestrukturovaných položek, které se používají k ukládání datových hodnot, jako je hash nebo mapa.
def test(): a = dict(); a['omg'] = 'javatpoint' a['i'] = 122 return a # Driver code to test the above method a = test() print(a)
Výstup
5. Použití datové třídy (Python 3.7+)
from dataclasses import dataclass @dataclass class Book_list: bookname: str cost: float quantity_of_book_available: int = 0 # This function is used to calculate the total cost of the books def total_cost_of_book(self) -> float: return self.cost * self.quantity_of_book_available book = Book_list('Python programming language.', 499, 10) i = book.total_cost_of_book() # print the total cost print(i) # print the details of the book print(book)
Výstup
Funkce vracející jinou funkci
V programovacím jazyce Python je funkce ve formě objektu. Uživatel tedy může vrátit funkci z jiné funkce.
V níže uvedeném programu vrací funkce first_add funkci second_add.
kyselé vlastnosti v dbms
def first_add(x): def second_add(y): return x + y return second_add i = first_add(20) print('The value of x + y is', i(10)) # second function def outer_func(x): return x * 5 def func(): # return the value in the different function return outer_func # storing the function in z z = func() print(' The value of x * y is', z(10))
Výstup
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