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Welcome back.

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In this lesson, we are going to be looking at math, random, so every game you produce, almost every

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game you produce is going to need some type of way to produce some type of unexpected result.

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And you can do that with math.

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Random and JavaScript provides a nice, neat way to return a value, a random value, anywhere from

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zero to one, but not inclusive of one.

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So it's anywhere from zero to almost one.

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And there's an example here on their website.

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So if you go down here and hit run, you can see that the math random multiplies by a value and this

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is going to return back the number that we're have a possibility of returning.

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And the reason that we use math floor is to get rid of basically the decimal with all the different

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values to it.

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So what math floor does is it allows us to bring the value down at least integer value.

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And basically what it's doing is it's just cutting off any of the decimal points.

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So you can think of it that way, that even if it's five point nine five, it ends up as five five point

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zero five still ends up as five.

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Let's go ahead and try this out and bring this into our application.

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So using math random and this is another one that we're going to have to reuse.

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So just create a function for it.

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And we could call it randt, be expecting a numeric value to be passed in there and creating a temporary.

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So we're going to use the math, random value, the math, math, random method, and we're going to

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multiply it by whatever the value of numbers is.

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So when I refresh it here and I'll show you how that's going to work.

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So, Rande, and let's put in a number of 400, and we do need to return that to see a value there.

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So temp.

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So let's return that back.

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So try that one more time round and we'll try four hundred again.

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We can see that it's getting a random value being returned back.

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So this is always going to be a different value and it's going to be anywhere from zero all the way

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up to three ninety nine point nine nine nine nine nine and so on.

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And in order to clear up all of those decimal places, then this is where we can use math flaw that

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will give us the ability to clear up those decimal places.

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So in those instances when you don't want to see all the decimal places, you can just add that in and

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we can do a quick refresh.

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And now you can see that we can type in rent.

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So try that random four hundred again and you can see that we are getting just random values to it.

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So we're getting without any of the decimal places, so are able to return back these random values.

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And this is actually exactly what we want within our gameplay and we're going to be using this random

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function several times coming up.

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So go ahead and try this out.

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Added into your project and get familiar with using the math random and also the math floor to get rid

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of the decimal places so that you have a nice clean number that's being returned and if you want to

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return it back.

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So essentially what's happening here is it's returning back a value from zero to whatever the number

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value here is not matching that number of value.

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And if we do want to return back one to four hundred, we could always add one in there.

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But I'm not going to do that.

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I'm just going to leave it as anywhere from zero to three ninety nine.

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So it'll never hit 400.

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So even if we do math random and if we do two, you're going to see that no matter how many times I

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do it, it's not going to hit two.

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So it's going to be either a one or a zero.

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And that's where if we wanted to have it as a one or a two, then that's why we'd have to add in a one

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there, because, again, we are using the math for.

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So go ahead and try this out for yourself.