Functions are a way of writing code whereby you group together a set of "tasks". Therefore, instead of writing tasks individually, multiple times, you simply use the Function that houses the set of tasks.
This means if you have a repetitive task, you do not have to write the code over and over. Just write the code into a function and use the function to do the task.
Functions will be building blocks for constructing complex codes.
Structure of a function
Functions start with a
def, followed by a function name and parenthesis, the docstring (optional), the function statements (i.e. codes) and ending with either
return, pass, or nothing at all. Watch the accompanying video for a more detailed explanation.
Python functions usually looks something like this:
def functionname(arguments): """This is the docstring that explains what this function is supposed to do""" function statements return
Calling a function
To use the function we simply call its name by writing
In this example, my function name is hello.
Note that this function does not have a
return statement, otherwise known as a void function.
Here is another example of a void function. The function rounds any decimal number that a user inputs to 3 decimal places.
Write a function that will return the number 1.2347586839402 to 5 decimal places
From 1.41 to 4.58