1

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Some more operators, we have unary operators, so let's say we have Vergès equals nine.



2

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How would I change Vare, let's have I equal to minus nine?



3

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Well, your first instinct is to go minus nine, but if there's a relationship between G and I, we



4

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would say you can just have minus G as the negative version of G.



5

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Now that little minus in front is called a unary operator performs an operation on one thing, which



6

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is in this case, G.



7

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You can of course just have that totally alone as minus G.



8

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Now, that doesn't replace gas, always nine minus G is just used in its own context.



9

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So that's a unary operator.



10

00:00:49,940 --> 00:00:50,570

What else have we got?



11

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We've got a compound operator.



12

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If I want to add one to I, for example, I could say I equals I plus one.



13

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Seems straightforward, so we take the old version of I add one to it and then put it back into I,



14

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but as a shorthand way of doing it, and that's plus equals one.



15

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So what it do is recognize that plus equals wants you to take I and then add whatever number you've



16

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put on the right hand side to I.



17

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Same works in reverse ie minus equals one.



18

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So if we run all this we should come back to the answer of minus nine.



19

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So minus eight and we come back to minus nine.



20

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Simple enough, what else have we got here?



21

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We got logic, logic, logic, logic.



22

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So.



23

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You wouldn't have this statement sitting alone I equals equals g for a start, you'd use it to check



24

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something.



25

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In this case it's checking if I is equal to G and when it says equal to it means exactly.



26

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Number one, is it an integer?



27

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Number two, is it the same value.



28

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You've got to be careful when you're checking if things are equal because if you have a double that's



29

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a nine and you have an integer that's a nine.



30

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In some languages they're equal.



31

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In other languages, they're not in JavaScript.



32

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If you have an integer nine and a string nine and use two equals, they'll be equal.



33

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But if you use three equals, they will not be equal because they are different types.



34

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So you've got to be careful with comparison strings and always check, always, always check that the



35

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comparison is what you expect it to be.



36

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So let's move on with some more comparison operators.



37

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Let's have I not equal to.



38

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So if I is not equal to G, this will return true.



39

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If it is equal to G, it will return false as in it's the reverse of this first one and then we have



40

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a whole bunch of others.



41

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I is less than g we have I is more than G.



42

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I is less than or equal to G.



43

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And can you guess the last one is greater than or equal to G.



44

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So these last to include the value that that's the flipping point of that statement, these two don't



45

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include it, so.



46

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If I was one and she was one, that's not true, that's not true, that is true.



47

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And that's true.



48

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And that's true because we also have equals as part of those greater than or less than statements or



49

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logic operators.



50

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OK, now we have what else do we have here?



51

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Oh, I have a little example for you.



52

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That's Havar equals true.



53

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So this is a boolean.



54

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It's either true or false.



55

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If I want to print the opposite statement of E, I would have print not e exclamation mark means not.



56

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So if we run that, we should get a printed force and we do.



57

00:04:00,060 --> 00:04:03,460

Okay, so those cover a whole bunch of operators.



58

00:04:03,740 --> 00:04:05,060

Let's grab your homework.



59

00:04:05,090 --> 00:04:06,500

Oh, you're in luck.



60

00:04:06,860 --> 00:04:08,480

There is no homework this time.



61

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Congratulations.