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Welcome back. Now, let's talk about

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parameters and arguments.

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See a parameter is basically an input

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that we can add to a function in order to customize its behavior

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in this case right now, in the previous example,

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the name of the function, which is great, it didn't have any parameters at all.

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It's basically empty.

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That's why

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when we said OK, print and then simply hello world and then we call the function.

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All it simply did was just simply say hello world.

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But what if we now want to add a particular parameter inside in this case right now,

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I'm going to come in here right now and say name.

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OK.

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So the parameter right here is called name. And now

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I want my function to say

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hello and then the name that will be provided.

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So

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I'm going to come over here right now. Let's use the F string.

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And now I'm going to add my curly braces, color brackets rather

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and call it name.

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OK.

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So now check this out

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when I'm calling my function right now, I can add what we call the argument.

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When you're passing a value to the function,

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it's going to become an argument.

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Please note the difference between parameters and arguments

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up here. When we're first defining the function,

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we're gonna use the parameter. The parameter is

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basically all saying, hey,

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we're providing you with this input and I'm going to use

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this input to customize how you the function grid will behave.

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However,

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once the function has been created,

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we've told what the function is supposed to do in this case right now.

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Hello and then name the parameter.

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When we call that function.

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When we want to provide a value, it's going to become what we call an argument.

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So in this case, right now,

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if I wanted to greet, let's say Alice, for example, right,

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Alice right now is the argument. And if I was to run the program,

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there you go. It says hello, Alice. What if I wanted to greet? Let's say Bob,

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right,

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Bob,

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let's go ahead and run the program and there it is. Hello, Bob.

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These are

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parameters and arguments.

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However,

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we can also have multiple parameters

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in our function.

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So far right now, we've only been working with one single parameter which is name.

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What if

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we wanted to create a function that will add two numbers together?

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How are we going to do that? Well,

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we can start off by defining the function name. So I'm going to call this one. Add

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numbers,

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add numbers will be the name of the function.

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And now inside

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we're going to provide two parameters which are going to be A and B

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colon.

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OK?

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Now

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return

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A plus B,

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we haven't talked about the return function

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or return statement yet.

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What return does here is that it's simply

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going to return the value

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of a particular operation. In this case right now

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is going to return

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the values of A and B when they are added together. That's what the return does. So now

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I'm gonna come in here

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and say uh results,

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OK? Results

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is going to be equal to

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add

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numbers.

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OK? And now inside

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I can add the two numbers. I want to add, let's say five and six.

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And now all I will have to do

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is to simply print

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the result.

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And there it is.

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If I run my function,

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there you go. 11,

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you see how this works. First of all, we created a function

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but isn't the defined function called add numbers. OK?

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That's the name of a function.

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And then we said, OK, our function is going to receive two parameters A and B.

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And now with the return, we're basically defining what the function is going to do.

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It's going to return the value of A plus B.

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Now,

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all we need to do is to create a variable

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that will store the value of our function.

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So now the variable here is called the result, which is equal to add number.

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The name of the function call in right now

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with the two values which are five and six.

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And now we simply printed out results which is equal to 11.

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That's exactly how parameters arguments and

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the return function also works.

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By the way before

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I run up the video,

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just a very quick word on the return statement.

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It's used for two main purposes. OK?

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The first purpose is typically to exit a function

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so you can use it to stop function execution.

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Second is to return an actual value. So

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as an example,

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let me just show you real quick if I set the fine and then greet,

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OK,

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let me add

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empty parameters in here.

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And I said print, hello

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and then I said return,

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all right. But then after return on another line, I also say print

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and then let's say, uh

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let me say

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my coats.

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Hello,

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Jack.

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You can even see right now that within our replete,

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it's

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the text itself is kind of faded out,

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meaning that Python will not execute this particular

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line. So if I was to run,

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you can see right now it does absolutely nothing at all.

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But that's because I haven't called the function yet. So

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let me come over here and say greets and then

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brackets and there you go. So

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if I was to run the function right now, you can see all it says is going to be hello.

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Why? Because return right here signifies that, hey,

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stop the execution of the function. It shouldn't go beyond this particular line

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and that's why we only have hello. However,

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if I was to remove

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the return statement

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and I run the program again, you can see right now it says hello and then hello Jack.

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So this is another use of the return statement.

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You can use it to stop function execution or like I showed you earlier,

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you can use the return statement to return a particular value.

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Thank you for watching the video. I will see you in the next class.