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Hello and welcome to this video.

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In this video I'm going to introduce you to a pilot on set.

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The set is a type of data structure in python what is a python set is set is basically a collection

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of values.

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The values in this set are not ordered.

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That means they are not in any particular order and the values in the set are not indexed.

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This is because they are not ordered.

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So it's difficult to index them.

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The set allows you to add values to it.

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However you cannot change the values that are already in the set.

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This is very important.

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You can add values to a set but you cannot change existing values.

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One way of creating a set is by giving the set a name.

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Try to give your set a descriptive name that reflects the type of values it stalls and then you add

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curly braces and inside the curly braces is where you indicate the values that are going to be stored

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in the set.

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I have got my text editor opened.

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I'm going to be using the text edit or code item.

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I've also created a python file and I've coded my set dot P Y.

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So that's the name of the file.

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He must have a dot P Y to make it a python file.

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So I'm going to create a set.

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So I give the set a name I'm going to call it fruits and I use the quotes to to assign values and the

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values has to be placed in inside curly braces.

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So I'll now add the values the first value I'm going to has it's going to be grapes.

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You separate a value with a comma.

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Now I'm going to add another one called apples onto a comma.

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Now add one more and I'll call this berries.

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So that basically creates a set it is difficult to access the individual elements in a set because they

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are not indexed so they are not in any particular order the orders can change.

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So you can't access the value from the index because they are not index.

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However you can loop through and print out all the elements in a set and you can do that using the for

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loop.

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So to do that I can just say for x in fruits.

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Okay.

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And doing the column.

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So the x represent each value.

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I can still say print x and what that will do it will print all the elements inside the set.

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So let's see how that works.

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Let me run this python file inside my command prompt so I've navigated to my desktop which is where

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the python file is.

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So in order to run the file I just call it by its name so I'll save my set dot P Y and our press pointer

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and you can see it prints out all the elements inside the set.

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Another way you can create a set is by using a constructor function.

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So the constructor basically is a special type of function used to create objects.

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So if I wanted to create a set code animals.

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This is how I would represent it when you're using the constructor function.

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Notice you have double parenthesis.

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So I'm going to create a set using a construct of function.

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So you start with a name.

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I want to call it and we'll call it animals.

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Now say equals two and I'm gonna have double parentheses inside the inner parentheses are specify the

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values that I want to add to the set first values a line second value.

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I will say Tiger.

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I'll add one more and I'll make this one a bear.

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So basically created another set by using a constructor function.

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Now if I wanted to print the values of this set on the screen I can do what I've done here.

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On line two or three just do the same thing here and that will loop through and print out the elements

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inside that set.

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If you want to count the values in a set you can do that using a special built in function code Len.

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If you just add the name of the set inside the line function that will print out the values in the set.

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So let's try and print out the values inside the set code animals.

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So the way we'll do that is to do a print inside that print function we had or not up onto a code.

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Len and inside our Len function will pass in the name of the set which is animals which chose to control

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as to save on the window.

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If you on the Mac just to comment yes.

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And that will save the file.

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So now if I run my file again which is my set the P Way it will execute the code.

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You can see here this print x here print all the values from the first set which is fruits.

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And this line of code three here basically is this here way is print in the length of the values in

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this set called animals you can see there are three in the bed the tiger and the lion.

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And that is what this value 3 represents.

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So that's set for these videos.

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Thanks for watching.