Return values from a function

- [Instructor] Let's take our function one step further. Right now the function is logging the results directly in the console as it runs from within the code block. That works in some cases but not others. In many cases you want the function to do something and then return a value back to you to process further before you display it, either in the console or in the web page itself. To get that to work we need to create a value, and then return it where the function is called. I'll start out by setting up a new variable called result, then I want to change what happens inside this ternary operator, so I'll take out this console.log("a: ", a) and replace it with result.

And here I'll assign an array to result that contains firstFraction, followed by the value of 'a'. Then we'll do the same for when 'a' is not the biggest. result equals array secondFraction and the value of 'b'. Then finally I return result to where findBiggestFraction was originally called. Now when I save this, nothing happens in the console, and that's because although findBiggestFraction is sitting with the result, we're not actually doing anything with it.

And here we now have options. I can either simply console log out findBiggestFraction, calling out firstFraction and secondFraction, and that works fine. Or, I can create a new variable, fractionResult, set it equal to findBiggestFraction, and then console.log(fractionResult).

And here we see the point of returning values from a function. Once the value is returned you can do many different things with that value and you can choose when to actually output it in the browser. So, why have I done all these things? I have pretty much taken a very simple operation and made it super complicated. Well there's a simple reason. Right now if you look in the console, although you have a bunch of information that says, firstFraction 0.75, you don't really understand what this is all about. I've created this more complex function so I can provide some context to my answer.

Watch this. First I'll console.log out the firstFraction value, once it's calculated. So I'll say, "First fraction result" and then the value of firstFraction. Then console.log "Second fraction result" and the value of secondFraction. Then we'll take this array over here that has both the name of whatever value is biggest and its actual value, and combine it into a longer string.

So I'll say, console.log "Fraction" and then get the fraction name, which is fractionResult, and here we're looking for the index 0, which is the name. Plus, "with a value of" plus, then we're getting fractionResult again, and this time we're looking for the value which has an index of 1. Plus text, "is the biggest!" Save that.

And check out my console now. First fraction result: 0.75. Second fraction result: 0.71428 blah, blah, blah. Fraction firstFraction with a value of 0.75 is the biggest. And there you have it, a complete named function with arguments that returns a value to be used elsewhere.