R Programming 101: How to Define Variables

Key Takeaways

welcome back to the data professor YouTube channel if you new here we cover about data science concepts tutorials and explainer videos and if you're into this kind of content please consider subscribing if you're wondering how to get started in our programming and how you can use our programming for data science projects then listen on so in this first video as part of a series of video we're gonna cover about the the fundamental part of a the our language so as you may know our language is very important for allowing us to do some statistical analysis of our data particularly for pre processing the data making visualization and which will also allow us to gain insights into the data and create predictive models so let's get started fire up your terminal window and fire up our so you just type in R so it's a capital R and hit enter and then here you are you're in the our environment so let's create our first variable in R so let's get started by firing up your terminal window okay and when you're in terminal you see a blinking cursor here so let's type in R capital R and so this brings you into the r programming environment so this for example type in 5 and then you will see that it also returns 5 and if we type in 5 times 6 you see that every turn study so it does multiplication here so let's try 15 / 5 so much division 15 divided by 5 so you get 3 so let's now define our first variable so let's be fine a let's assign a value of 5 and let's assign a value of 6 to be so this is the example that we have done already 5 times 6 and so let's create another variable cost C and then we're gonna have C multiply B and so this is type in C and then we're gonna get 30 because C is equal to a times B and a is equal to 5 and B is equal to 6 so 5 multiply minus 6 you get 30 so let's say that in the future a the value of a change is from 5 to 6 okay so as if that we have to define the equation C wants once more in order to get the updated value of 36 so let's say that a becomes 7 so so if you type C it still maintains the same value so we have to define it again so C equals to a times B so we're gonna define that once more and as you can see I just type in the edges press the UP button up key the arrow up arrow and it will give me the previous commands that I had tight so that I don't have to type it again okay so [Music] there you have that you have that some basic multiplication division you have defined a variable assign it with some values so let's say that you want to assign more than one value to your variable can you do that well of course so we're gonna make use of what we call a vector so a vector works pretty much like a an array in Python so if you think of it a vector and R is kind of like a bookshelf so within a bookshelf you have many shelves of course let's say that book in your book shop you have five shelves and on each shelves you have different objects so let's say that you have Apple on the first shelf you have an orange on the second shelf you have banana and the third shelf okay so it's define our variable let's call it fruits and then we're gonna have C which is when we want to define it back there so we're gonna have Apple we're gonna have orange banana tell about let's make our shelf into a three shelve books down so let's type of foods again let's say you're gonna have seen three values here apple orange banana so let's say that we want to get the values on the first shelf what do we do so you type in fruits and then you're going to use the bracket and then you're gonna type in number one so at the first position number one would be in the first position of the variable fruits so the first position and the value will return Apple so what happens if you type in fruits and any chance to balance it - yes we get orange and what happens if you type in 3 so you like to guess oh it's banana ok so there you have it you have created a variable which contains a vector of values and you have done subsetting by displaying the values in each of the shelves or each of the position in the vector and so give yourself a big 10 you have done a good job now okay so now you have created the content right inside the terminal the comment line and so now we're going to try art studio so we're gonna do the same thing in our studio so it's gonna look resemble like in the terminal so if I type in 5 I get 506 I get 6 times 5 times 6 ok 30 I assign a belly to a sign of belly to be I'll do C is equal to a times B by type C idea 30 ok so similar to what that we have previously lets you find a variable called fruits and then see the 21st element which is Apple and we're going to be fine staying at element which is orange we're gonna be third element which is banana first so we get three contents there it cooks and we got you want to get the first position foods and we want to get the second position detective first and the third position that's her okay so it works exactly like in the terminal and so now the good part is that you can also write their code and then you save it into a file so to do that you will want to click in file new file our script right and then you can type in or you could just copy what you got done here right and then you can save it into a folder of your choice I just save it into the Downloads folder I'll call it box are so no there's bad car is in capital they're unarmed so to run it you want to type in you want to click on run or you could type control-enter honey you can see it helps a bit so I can do like this again control enter control enter and you see that Apple will be returns okay thank you for watching please like subscribe and share and I'll see you in the next one but in the meantime please check out these videos