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Python Python Basics Functions and Looping Functions

Don't understand parameters

Can someone please explain to me what a parameter is and what it does? Thank you!

1 Answer

The Python doc defines parameters and arguments as follows:

Parameters are defined by the names that appear in a function definition, whereas arguments are the values actually passed to a function when calling it. Parameters define what types of arguments a function can accept.  

We define a function say_hello(name) below:

def say_hello(name):
    print("Hello {}".format(name))

name is the parameter

We call the function say_hello() below. my_Name is the argument passed to say_hello() method

my_name = "Ayub"
say_hello(my_name)    

Parameters help you call functions with additional information (name in the above example) and provide flexibility. Without them, if you wanted to print name, you'd have to keep changing the my_name variable insdie the say_hello() function again and again.

my_name = 'Patrick'
say_hello("Hello {}".format(my_name))