Original subtitles

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Hello everyone and welcome to the lecture on variables.

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This lecture we're going to go over some conventions on naming variables and how to assign the variables

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in R.

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Let's go ahead and jump to our studio.

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All right so here we are our studio and what I'm going to show you is just a couple of things that we're

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going to be learning as we begin our journey on learning the our programming language.

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And the first one we want to know is what actually comments or code.

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So what if you just want to leave yourself some notes either in your script or in the console.

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You can do is use a hash tag and this is similar to the Python programming language.

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And then whatever you write after the hash tag such as this is a comments.

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If you end up running this you'll notice that nothing comes out.

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So let's go ahead and show that in the console.

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So if I say something like print Hello enter and then if I were to do the exact same thing with a hash

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tag in front of it notice that I don't get any output because R won't read anything.

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Pass the hash tag because it treats it as just that comments.

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So that's one thing I want you to be aware of.

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And now let's go ahead and discuss variables and how to assign variables so variable names by convention

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.

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Start off with lower case letters.

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So if you had something like variable you would say use this assignment operator and then put in whatever

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you want to assign that variable.

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So what's actually happening here.

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We created a variable name.

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This case is called variable and we use the assignment operator which is this basically looks like an

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arrow which is nice for readability.

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So it's this less and and then a minus or a dash.

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So they form an arrow and then on the right hand side whatever data object or data type you want to

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assign to that very well.

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So for this lecturer it's going to be dealing with integers since that's something we've dealt with

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before.

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In the example of arithmetic.

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So here I am in signing the integer 100 to the variable called variable.

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So if I call variable again and then go ahead and just click enter in the council will return its assigned

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value which is 100.

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So let's go ahead and imagine another example will say bank and assignats 1000.

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So now if I call bank I get 1000 out as the assignments.

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So that's a variable assignment works.

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And you'll notice here in the environment if you ever want to know what variables you have or what values

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you have in your global environment for this session of Are You can reference this here.

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So just some quick style guides and convention points usually what you want to do is let's say you want

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to have multiple words in your variable name.

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What you would do is separate them by a period or dot.

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So we can say something like bank accounts and then assign that 100 so that's acceptable.

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Sometimes you also see this sort of notation bank and then instead of a dot They just write a capital

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A.

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What you won't see in our as often and is usually known as a bad style season.

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Underscore now it will still work completely So each of these is technically correct you can use all

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of these methods but the most common styles you'll see is this Fersen right here separating each of

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the words.

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All right.

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Later on when we discuss functions we'll go over the style guides for namea your functions and functions

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will actually usually start with capital letters.

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So finally just go ahead and show a quick simple example how you can use variables to perform calculations

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in operations that are.

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Let's go ahead and clear the cons..

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And here in Windows I'm clearing the consulars by doing control L as a shortcut for that.

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So I'm just going to go ahead and say make a variable deposit assign it.

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Let's just say 20 enter.

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So I have my deposit and I'm going to say bank accounts bank account and I'm going to reassign bank

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accounts as my current bank account plus my deposit.

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So notice here before I actually run this line my bank account variable is equal to 100.

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My deposit is equal to 20 after running this line.

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What's going to happen by click enter my bank account is going to be equal to 120.

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So that's going to be the 20 plus the previous 100 value of bank account and it's going to update that

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variable which is bank accounts and that's the basic way you can use variables in a variable assignment

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operations.

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In our ok player I think it's pretty straightforward.

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The main thing to go to this lecture is that this symbol this arrow symbol is what you're going to be

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using for variable assignments in our.

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Okay.

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Thanks everyone.

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I'll see you at the next lecture