Double Star or (**) is one of the Arithmetic Operator (Like +, -, *, **, /, //, %) in Python Language. It is also known as Power Operator.
What is the Precedence of Arithmetic Operators?
Arithmetic operators follow the same precedence rules as in mathematics, and they are: exponential is performed first, multiplication and division are performed next ,followed by addition and subtraction.
Arithmetic operators priorities order in Decreasing Mode:
() >> ** >> * >> / >> // >> % >> + >> -
Uses of Double Star operator:
As Exponentiation Operator
For numeric data types, double-asterisk (**) is defined as an Exponentiation Operator:
Example:
# Python code to Demonstrate the Exponential Operactor a = 2
b = 5
# using double asterisk operator c = a * * b
print (c)
# using double asterisk operator z = 2 * ( 4 * * 2 ) + 3 * ( 4 * * 2 - 10 )
print (z)
|
Output:
32 50
As arguments in functions and methods
In a function definition, the double asterisk is also known **kwargs. They used to pass a keyword, variable-length argument dictionary to a function. The two asterisks (**) are the important element here, as the word kwargs is conventionally used, though not enforced by the language.
First, let’s simply print out the **kwargs arguments that we pass to a function. We’ll create a short function to do this:
Example:
# Python Program to create a function to get a dictionary of names. # Here, we will start with a dictionary of three names def function( * * kwargs):
for key, value in kwargs.items():
print ( "The value of {} is {}" . format (key, value))
function(name_1 = "Shrey" , name_2 = "Rohan" , name_3 = "Ayush" )
|
Output:
The value of name_1 is Shrey The value of name_2 is Rohan The value of name_3 is Ayush
Now here is another example where we will pass additional arguments to the function to show that **kwargs will accept any number of arguments:
# Python Program to create a function to get a dictionary of as many names # you want to include in your Dictionary def function( * * kwargs):
for key, value in kwargs.items():
print ( "The value of {} is {}" . format (key, value))
function( name_1 = "Ayush" ,
name_2 = "Aman" ,
name_3 = "Harman" ,
name_4 = "Babber" ,
name_5 = "Striver" ,
) |
Output:
The value of name_1 is Ayush The value of name_2 is Aman The value of name_3 is Harman The value of name_4 is Babber The value of name_5 is Striver
The time complexity of the given Python program is O(n), where n is the number of key-value pairs in the input dictionary.
The auxiliary space complexity of the program is also O(n), as the program stores the input dictionary in memory while iterating over it.