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-: When looping in Python, one

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of the most common tools is this "range" function

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that we get out of the box with Python.

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And you see here that range, well, is a range object

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a special type of object in Python that returns an object

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that produces a sequence of integers

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from start to stop.

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Let's explore that a little bit more.

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If I print here a range, and I say "range 100"

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and I click "run,"

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I get range of 0 to 100.

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Hmm. So it looks like a topple, but it's not.

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It's a range object.

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It's a special type of object. And range,

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you can give it like this, which gives you a default

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of 0 to whatever you give it, which is 100

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Or you can just simply type 0, 100.

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And if I click "run," it's the same thing.

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But where "range" becomes really useful, and you'll see this

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in 99% of cases in Python, is in 4 loops.

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You see,

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besides "topples and lists and sets and dictionaries"

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"and strengths," you can iterate over a range.

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So for example, if I do "for i"

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in "range," and let's just

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say "item," or in our case, let's just do "number in range."

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And in here I do "print number."

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If I run this, you'll see that I'll get numbers 1

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to 100. And why is this useful?

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Well, using "range," I was able to loop 100 times,

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as you can see, all the way till 99 because our account

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starts at 0, and we're able to loop as many times

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as I want. So I can tell the loop,

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maybe we wanna loop a certain number of times.

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Maybe you wanna loop 10 times where I can tell the loop how

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many times to run.

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It's extremely useful.

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Maybe here we're performing some action where it says

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I don't know, email, "email list."

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So we wanna send 10 emails to an email list, for example.

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Well, again, I can just click "run" and I sent that email

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well a bunch of times, 10 times.

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Another neat trick is that, well, you might not

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even need "number," right?

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We're not really using it in our code.

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And often while you'll find in Python programs is,

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if a programmer doesn't need this variable, you just

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do an underscore.

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And this is just a variable.

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I mean, you could use it like this

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and you'll still get

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these numbers, but it just indicates

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to other people that, "hey,

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I don't really care what this variable is.

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I'm just trying to use 'range'

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so that we can loop over things."

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Let's say 10 times.

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Now, "range" also comes with a third parameter.

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And what that is, is the step over.

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So if I do two, and by the way

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default is one here, if I do two

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it jumps from 0 to 10 by 2,

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which is very, very handy.

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So what is "range?"

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Well, "range" creates a special kind

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of object that we can iterate over.

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Okay, what if I do minus oh, right here?

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What if I do -1?

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Well, if I run this, hmm,

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that's not going to work because, well, let me show you why.

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If I change this to 0

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and 10 and I do -1

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it's going to go in the opposite direction.

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But if I did just 10 and 0,

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that's not going to work.

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If we wanna do something in reverse,

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we just have to make sure that we add that -1

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or, if we wanna step back twice, then we click "run."

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So you have a lot of options to play with the range.

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You can do ascending, descending.

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One final thing, another place that you might see ranges.

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And, like I said, most of the time, they're in four loops

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but he can also do something interesting

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like, let's say, a range

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of 10.

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And then if we wrap this in a list,

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remember a "list function" allows us to convert something

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to a list.

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If I run this, did you see that?

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Let's simplify this so that this range is

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going to just be 2.

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If I click "run," you see that I

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loop two times

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and in here I'm going to print, First of all

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I'm going to create a range,

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an Iterable object that has 10 items

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and then I'm going to convert that into a list.

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So you can see here 0 to 9 into a list.

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So this is a quick way to create a list that well,

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has integers.

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A neat trick that you'll definitely use along your

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programmer journey.

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I'll see you in the next one. Bye-bye!

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