functions in python
Alright, let’s start with what functions actually are?
- OK, a function is a piece of code.
- A function may/may not accept input(s).
- A function may/may not return an output(s).
Why do we need functions in a program?
- Well, the Reusability of the code in a program is made possible through functions.
- The program can call these so-called functions, n - number of times.
- This showcases the best practice in a program called DRY.
DRY - Do not Repeat Yourself
- A code is said to be DRY if any given code does not repeat certain tasks
- A function implements this just by writing once and using whenever necessary.
Quick intro to functions in python
Creating a function
- To create a function we use the keyword
defmust be followed by the function name.
- followed by a parenthesis filled with formal parameters(optional).
- The statements that follow up makes the body of the function.
- Note: Any code written inside a function must be indented.
- Let’s see an example where I thank every one of my readers:
Calling a function
- To call a function we use the function name followed by parenthesis filled with actual parameter also known as arguments.
- This is when the code inside the function actually gets executed.
- Let’s see the same example and its output:
Hello there John Doe Thank you for taking your time to read my post ;) Hello there Jane Doe Thank you for taking your time to read my post ;)
Passing arguments to a function
- We can pass arguments to a function through the function call.
- We do this by writing the arguments inside the parenthesis of a function call.
- Didn’t you notice passing arguments to a function already? Look into the above example closely:
reader("John Doe") reader("Jane Doe")
- The function call
reader()passes the strings “John Doe” and “Jane Doe” as arguments to the function.
There you go, now you can create your own functions and play with it.