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Welcome back.

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The methods we're going to talk about when it comes to sets are right here.

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It looks like a lot, but they're quite similar.

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So hang in there.

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I have two sets for us are my set, which is one through five.

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And then your set, which is four through 10.

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Now, let's go one by one and see what these methods do.

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And if you've ever seen Venn diagrams in your school, for example, two circles that are overlapping

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each other, what we're about to do is quite similar to this.

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The first one is difference.

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And sets are very useful when having two sets and comparing them to each other.

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So, for example, in here, difference simply says my set dot difference and we give it another set,

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such as your set.

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If I print this right here and I click run.

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I get one, two, three, it's going to find the difference of the first, my set with your set.

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So any duplicates between the two, which is four and five?

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Gets ignored and it only shows the difference.

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That is one, two, three, what's the difference between my set in your set when viewed from my set?

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Well, your set doesn't have one, two, three.

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What about the next one?

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Discard again if we do my set.

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Don't discard.

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It says it removes an element from a set if it is a member.

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So here we can say discard.

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And if I do print.

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My set and I click run.

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I get none, but if I print here my set and I click run.

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I get one, two, three, four, because we've just discarded five, it modifies our set just to keep

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our working space clean.

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I'm going to comment this out.

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Next is Defence Update.

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So I'm going to say my set and then once again, let's see what difference update does.

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Remove all elements of another set from this set.

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So if I do your set here.

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And once again, I do print and I click run.

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Again, none, because it just modifies my set, so remember, we just have to have our print.

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And now this my set is updated with just one, two and three, because we're updating it so that the

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differences are removed.

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So four and five are removed, unlike difference where it just told you the difference without changing.

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Again, if we go back here and simply do my set.

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And I click run.

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You see that my set here was not modified right here.

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But then my set bottom was modified because of difference update.

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All right, a few more to go intersection.

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And this one, once again, my set and in here once again, let's see what it does.

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It just has an intersection with something else.

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Let's find out if I do your set here and I do print.

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And I run this.

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It's going to give me four or five, because that's the intersection, the two common things that might

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set in your said has.

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What about this disjoined?

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Well, if I do my set.

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And then your set.

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I feel like I'm saying those words over and over.

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Hopefully that's not too annoying.

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And then here, if let's comment this out, we run this.

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I get false is disjoined, simply says, hey, are those two circles overlapping?

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Do they have anything in common?

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If, for example, my said didn't had four, didn't have four and five and I click run.

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I get true because it's disjointed means these sets have nothing in common.

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Awesome, just a few more.

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The next one we're going to see is is subsect and is superset.

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But actually, before we do that, let's do union.

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Let's see what this does, Union.

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Well, say my set.

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And in here, we want to add the other set your set if we print this.

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And click run.

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I get one, two, three, four, five, six, seven, eight, nine, 10.

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What did that just do?

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Well, Union just united these sets together, but removed any duplicates, that's kind of nice.

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And as you can see, it created a new set for us, a return to a new set.

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By the way, there's actually a shorthand that you can do here in Python, which is the shift and then

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the key above your enter, which is right here, the straight line.

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So shift and then the backslash.

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But if you press shift, you'll get this little straight line if you print this.

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Well, remove the brackets here, let's run again.

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And you see, that works as well.

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And by the way, this also exists for intersection.

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Again, you don't see it that often, but with intersection you can do the same thing where you just

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do the end.

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And if you do that.

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It gives you the intersection of my set and your set.

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All right, I promise you, this is going to be short.

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So two other ones is subset and is superset.

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As you can imagine, my set if let's say my set only has four and five.

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And I say, hey, is my set, is that a subset of your set and I print this if I click run.

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It's true, set is a subset that is it's inside of the circle of your set because four and five is inside

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of it.

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So my set the entirety of my set is inside of this other set, which we call a subset.

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On the other hand.

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We also have this idea of superset, so if I do instead of a subset is.

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I'll get false because what my said is not a superset, it doesn't encompass your set, it's the other

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way around.

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Your set is a superset of my set.

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Because your seat encompasses everything that my set has, which is four and five.

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However, that was a lot, and you're asking yourself, there is no way I'm going to memorize any of

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that.

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Well, good.

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I don't memorize any of this either.

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As a matter of fact, I usually go to the Python documentation or just Google around.

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And because I know sets exist, if I ever want to compare, let's say, two sets I know to just go here

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and find the tool that I want.

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That's the cue of a programmer that I keep mentioning over and over.

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It's not memorization.

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It's the ability to know that there's tools that you can use and being able to Google for them.

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I know it doesn't sound exciting because in movies you see everybody typing super fast and coding everything,

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but that's just not real life in real life.

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You just Google around, find solutions, because by now, you know what sets are.

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You know, what sets can do so that you can Google for methods that are appropriate to your problem.

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I'll see you in the next one.

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Bye bye.