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[no audio]

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Friends, here we are going to discuss the very first

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data structure of your Python, that is list data structure.

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So first let me open my Notepad and I will show you how

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to define a list.

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So guys any name you can take. Simply

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I am taking 'my_list='

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this one, this is an empty list.

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So if you want to create any list with some values, right

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let me take 'my_list1=', so

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[no audio]

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you can provide any type of data.

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Right. Now, so this is the way how you can define your list.

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And guys, the very first thing in your real time,

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I mean very important point in your real time from list is

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sometimes you need to convert your list into Boolean, right.

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You cannot convert your data into some integer, float, or string,

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or complex because list data structure is the combination of data.

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[no audio]

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Right. Fine. Now in case if I convert our data into Boolean

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what will happen? Right.

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So for that let me take, let me open my command line of Python.

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[no audio]

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Right. Simply let me copy

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this as one list, no. This is empty list. Be clear, empty list.

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So if I try to convert empty list,

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[no audio]

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right, into Boolean, see that, 'False'.

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This is very, very important. Empty,

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if anything is empty, if you convert into Boolean that is

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'False'. Now instead of empty

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let's say some random data, right, any data, now if I try to

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convert you will get 'True'.

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So these two points are very, very important,

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okay. So 'bool(

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[no audio]

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empty_list)'

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[no audio]

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is equal to

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'False',

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'bool(non_empty_

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[no audio]

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list)'

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[no audio]

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equals to 'True'

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It's very useful case in your real-time, guys.

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[no audio]

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Okay, fine.

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Now guys,

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[no audio]

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you know the string operations with the index values, or based

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on index values in your string

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you are taking, you are displaying particular

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character from your string.

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Let's say I have a word called

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"hello". Already

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we know this, just I am recollecting that concept. "hello".

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So once if you define your string in this way, what will

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happen? Your Python will assign the index value for "h" is 0,

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the "e" is for one, second "l", third "l",

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and then fourth, right?

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So five let us are there,

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0 to 4 indexes are there in a positive way, or in a negative

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way - 1, - 2, - 3, - 4, and then -5. So you can go with the

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negative or positive.

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Right. So these are the index values for your strings. The same way

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whenever if you define a list,

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for list of values also Python will assign some index values.

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Let's say this is your list then 3 is at index 0, 2 is at

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index 1, 4 is at index 3, sorry 2, this entire thing is one

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data in your list.

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This is at index 3, and this is at index 4.

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[no audio]

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Right. I will do one thing.

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Even negative way also,

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so this is at -1,

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this is at -2, 4 is at -3, 2 is at -4, and

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then 5 is at -5.

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I will take, I will write a simple Python Script to give the

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clarity on this list with index operations.

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Let me open my Sublime Text. So I am taking this as my

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[no audio]

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'working_with_a_list'.

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[no audio]

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Fine. Observe that, first thing, how to print your

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list. So I am going to 'print(my_list)',

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and I want to see type of your data structure.

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Anyway, we know that is a list data structure but through

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Python you can find that.

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See that, we are getting class as a list.

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[no audio]

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Right. Fine. Now, let me comment this.

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So guys, we are saying that Python is assigning some index

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values for your list of values.

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So very first value is 3. 3 is at index position 0. Now if

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I want to print very first value from your list, or if I

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want to take first value from your list, I have to take index 0.

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Right. See the output what you are getting,

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3. Then I want to get, suppose some "python",

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I want to display this output.

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So "python" is at one, two, three, fourth value. Fourth value means

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index is 3 because you know index starts from 0.

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This is 0, 2 is 1, 4 is at 2, and "python" is at 3.

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[no audio]

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Right. Now I want to get

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[no audio]

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fourth value, means index is 3.

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[no audio]

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Yes, you are getting, and this is the way how you can get your

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particular value from your list based on positive index values.

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Of course, you can also use negative.

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Let me take 'print(my_list(-1))'. You know -1

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means by default last value.

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It may be string, or it may be list, while going forward it

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maybe tuple also.

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[no audio]

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See that. Or let's say I want to get,

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[no audio]

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from last second value

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I want to get. That means index value is -2. If you take

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-2 you will get

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from last second value.

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That's it, right. Now

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let me comment all this.

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[no audio]

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So this is the way how you can access your

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[no audio]

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list of values

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based on index. And one more thing.

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See as of now if I run this maybe with -2 or I can take this

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also, no problem,

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[no audio]

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both will give same result, right, because in positive way

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your Python index is 3, in negative way index is -2,

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right. You can take anything, no problem.

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I am taking suppose positive index, and see the output what

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you are getting, "python".

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Now guys in case if I ask, write a syntax to get from your

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list this data and in that I want to display only "y" letter.

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If I write something, it has to display only "y".

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So first of all you have to get this data. To get that data

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already we have a syntax, and that is a string. In string "y" is

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second letter. In the output, just observe this output. Now because

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of this you are getting this output. In this output "y" is

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at second position, means index is 1,

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no. Now see that what I am doing, and see what you are

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getting by doing this.

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You are getting letter "y" because that is a string. Again strings

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we can access with the help of index values.

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Right. Guys you just try to practice in this way also.

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Then, you know in your

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list, right,

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I mean strings, if I write something like this,

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what is the meaning of this?

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Entire, I want to get from starting to ending.

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This is the way, or simply you can write simply

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'my_list' also will work. This also, will give your entire list.

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But if I want to print something like first index to last,

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'1:'. Now you will get '2, 4, "python", 5.6', because we are mentioning

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1 no. 1 means index 1. Index 1 is nothing but 2 data; 2,

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4, "python", 5.6

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you will get. See the output.

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[no audio]

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Right. I want to get from 0 to last, same as your,

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[no audio]

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so guys this syntax,

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or let me write all these syntaxes because all

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will give same result.

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This will be helpful for your online exams. 'my_list' or 'print(

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my_list[:])'.

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see all the results are same.

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So if you want to print a list you can follow any one of this.

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That's fine. Now what my intention is,

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I want to print something,

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like you know, first index to only

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[no audio]

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three more values. 'print(

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my_list', from first index 3 more values. Then 1 + 3, 4.

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Then you will get

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three more values. From 1, three values.

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[no audio]

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So guys, you can also consider like 4-1 means range is

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3, you are getting three values. That's it.

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[no audio]

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Okay, fine.

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Now this is all about, yeah, we have one more thing.

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[no audio]

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So guys if I want to change a list of values based on index,

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let's say as of now index 0 value is 3 but I want to make

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it as some other value then 'my_list[0], I am writing some

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45. See the output.

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Yeah. After that, I need to print it,

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no. Let me print.

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[no audio]

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Let me comment this line. Because if you print then only you

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can see the modification, right?

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So after your operation just try to print your list and see

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the output what you are getting.

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Your index 0 value you are modifying into 45.

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Right. Your index value

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you're modifying into 45, right?

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[no audio]

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Fine.

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[no audio]

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Now, let me comment all these lines.

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[no audio]

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And one more thing guys because of this data,

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I mean this syntax, you are able to modify your list value,

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right. You're able to modify your list value. That means lists

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are mutable. At any time

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you can change your list of values, part of your list, right?

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So this is very, very important. So lists are mutable.

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[no audio]

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And once again, you know strings are immutable. Once if we define

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your string, you cannot change the part of your string, but

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see that, you can change the part of your list. Because this

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operation is allowed,

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no. That means you're changing some value in your list, so

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lists are mutable.

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Fine. So these are based on index, guys, operations on your list,

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right? Let me take some other operations.

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[no audio]

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'my_list', I am taking.

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Let's say 3, 4, 5, something, value.

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I want to explain the different way.

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Fine. Now

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first of all, what are the operations available

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with your list,

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how you come to know that, right? Nothing

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is there. Just to go to your command line, Python command line.

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Already we have a 'my_list', right. Some list

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is there. Simply do 'dir' of your list.

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[no audio]

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See. Guys, these are for your documentation

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purpose because the list is actually an object for your

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some of the Python classes, okay.

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That's why these are the documentation related things.

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So you have to know only without underscore whatever you

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have, that are you our operations.

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[no audio]

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Right. Now, see what are the operations there - append, clear, copy,

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count, extend, index, insert, pop, remove, reverse, and sort.

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First let me go with append, insert, extend.

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Yeah, I will go with first index because that is also one

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of the important one. See let me, index is nothing but getting

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an index value of a particular value. 'index()', let's say 5

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index. What is the index of 5? 1, because 5 is occurring at

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[no audio]

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first position. Sorry, second value means index is 1, right.

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Okay. Now,

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[no audio]

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then that is one thing. You may get doubt, in case if you have

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multiple fives in your list, right. Suppose

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I have somewhere here 5.

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[no audio]

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Now I am running. You're getting index 1 means this index

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value. Then what about this 5?

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So in case if you are getting 1 no, just try to search

259
00:13:57,100 --> 00:14:01,900
after index 1. That means from index 2 just try to search

260
00:14:01,900 --> 00:14:04,000
and see if there are, if there is any one more 5.

261
00:14:04,000 --> 00:14:07,800
Yes, it is there at 6th index, means seventh value.

262
00:14:07,800 --> 00:14:10,200
[no audio]

263
00:14:10,200 --> 00:14:12,200
Okay, fine.

264
00:14:13,000 --> 00:14:15,700
So you don't worry about if you have multiple values how

265
00:14:15,700 --> 00:14:18,700
to work with that, we'll have a separate section for that.

266
00:14:18,700 --> 00:14:22,300
There we'll discuss it. For time being if values are unique

267
00:14:22,300 --> 00:14:25,100
how to work with them, okay.

268
00:14:26,500 --> 00:14:30,300
Fine. Now, actually the good thing is 'regex'. We have regular

269
00:14:30,300 --> 00:14:32,600
expressions. There we can do lot of things.

270
00:14:33,300 --> 00:14:36,700
Meanwhile, we just try to no minimum things from your list.

271
00:14:38,600 --> 00:14:43,400
Okay, index done. Then let me take count also. See count is

272
00:14:43,400 --> 00:14:45,400
nothing but, let me print

273
00:14:45,400 --> 00:14:47,800
[no audio]

274
00:14:47,800 --> 00:14:49,000
your list '.'

275
00:14:49,000 --> 00:14:51,200
[no audio]

276
00:14:51,200 --> 00:14:55,000
'count()', any number. Let's say I want to count number 10,

277
00:14:55,000 --> 00:14:56,900
how many times it is there in my given list?

278
00:14:58,400 --> 00:15:01,500
0 times. I don't have any 10 in my list, right?

279
00:15:01,600 --> 00:15:04,700
That's why are getting output as 0. Now,

280
00:15:04,700 --> 00:15:05,600
let's say suppose

281
00:15:05,600 --> 00:15:09,200
I want to count a number which is having suppose

282
00:15:09,200 --> 00:15:11,200
[no audio]

283
00:15:11,200 --> 00:15:14,800
Three times 5 is there, no. Now I am going to count number

284
00:15:14,800 --> 00:15:17,300
5, how many times it is there in my given list?

285
00:15:18,600 --> 00:15:21,000
Three times. That's it.

286
00:15:22,000 --> 00:15:23,000
Okay.

287
00:15:23,800 --> 00:15:26,600
Fine. Now that is about count.

288
00:15:26,600 --> 00:15:29,000
[no audio]

289
00:15:29,000 --> 00:15:31,000
Any next related operation?

290
00:15:31,000 --> 00:15:34,600
[no audio]

291
00:15:34,600 --> 00:15:38,900
Yeah, 'clear'. Very simple one. Clear is nothing but, see guys before

292
00:15:38,900 --> 00:15:40,600
running my 'clear' operation

293
00:15:40,600 --> 00:15:41,900
I am printing 'my_list'.

294
00:15:41,900 --> 00:15:44,300
[no audio]

295
00:15:44,300 --> 00:15:52,200
Then 'my_list.clear'. Then 'print(my_list)'. See the output.

296
00:15:53,400 --> 00:15:55,000
You are simply clearing your list.

297
00:15:55,200 --> 00:16:02,500
So that is the usage of your 'clear'. Guys, if you observe sometimes

298
00:16:02,500 --> 00:16:04,500
I am doing operation in print itself,

299
00:16:04,500 --> 00:16:06,800
sometimes I am doing operation separately.

300
00:16:06,900 --> 00:16:13,100
The reason is, here you are trying to get the, fetch the information.

301
00:16:13,100 --> 00:16:15,100
This operation is like counting, no. You're counting, you are

302
00:16:15,100 --> 00:16:16,100
not modifying.

303
00:16:16,700 --> 00:16:19,600
So modifying operations don't do with print.

304
00:16:19,600 --> 00:16:21,800
[no audio]

305
00:16:21,800 --> 00:16:24,600
Okay. Directly, whatever the operation you are performing

306
00:16:24,600 --> 00:16:28,800
that modification will modify in the original data itself.

307
00:16:28,800 --> 00:16:32,800
Because lists are mutable, whatever the operation you are performing

308
00:16:33,100 --> 00:16:36,600
that operation will modify the original data itself.

309
00:16:36,600 --> 00:16:38,500
[no audio]

310
00:16:38,500 --> 00:16:41,300
Right. So that's why I'm not using this in 'print' statement.

311
00:16:41,300 --> 00:16:44,800
When you will use 'print'? If you want to see the existing information,

312
00:16:44,800 --> 00:16:48,100
that type of operations you have to work with 'print', or you

313
00:16:48,100 --> 00:16:51,000
can also store that result into some variable and that variable

314
00:16:51,000 --> 00:16:54,300
you can print. Let's say I want to count how many times 5

315
00:16:54,300 --> 00:16:57,800
is there, so directly I am printing the count. Instead of that

316
00:16:57,800 --> 00:16:58,600
what I will do,

317
00:16:59,800 --> 00:17:06,200
'cont_five', any variable. Then in this way. And I can print this variable.

318
00:17:06,598 --> 00:17:09,400
So why should we take extra variable and why should we print

319
00:17:09,400 --> 00:17:14,000
that? That's why I am directly printing. But don't print this data.

320
00:17:15,098 --> 00:17:16,700
Right, this is operation.

321
00:17:17,000 --> 00:17:18,300
You're modifying something.

322
00:17:18,500 --> 00:17:22,700
So if any operation is related to modification, that directly

323
00:17:22,700 --> 00:17:24,900
perform in this way. Don't use print for that.

324
00:17:25,800 --> 00:17:29,300
Anyway, after some practice you will come to know that but

325
00:17:29,300 --> 00:17:30,800
meanwhile just remember that.

326
00:17:32,300 --> 00:17:36,200
So 'clear' is done. Then let me go with 'copy', right?

327
00:17:36,400 --> 00:17:39,300
See guys, if you want to assign one variable value to other,

328
00:17:39,300 --> 00:17:44,800
let's say 'x=4', and I want to assign 'x' value to

329
00:17:44,800 --> 00:17:50,000
'y'. I can assign in this way, right. Same way, suppose 'my_new_list'

330
00:17:50,000 --> 00:17:53,099
I am taking equals to 'my_list'.

331
00:17:53,099 --> 00:17:56,700
[no audio]

332
00:17:56,700 --> 00:17:59,400
Okay, or 'my_one_more_list'

333
00:17:59,400 --> 00:18:03,600
I am taking equals to 'my_list.copy'.

334
00:18:04,900 --> 00:18:06,500
Both are same. Nothing there.

335
00:18:06,500 --> 00:18:09,500
You're assigning this values to this one. This

336
00:18:09,500 --> 00:18:10,500
values to this one.

337
00:18:12,200 --> 00:18:15,300
Both are same, but there is a small difference that is, whenever

338
00:18:15,300 --> 00:18:18,900
if you directly assign in this way, you are not going to

339
00:18:18,900 --> 00:18:23,100
create a new memory location instead of that, instead of that,

340
00:18:23,100 --> 00:18:24,400
be clear, suppose

341
00:18:24,400 --> 00:18:25,400
assume that your list

342
00:18:25,400 --> 00:18:27,500
is there somewhere in RAM memory,

343
00:18:28,200 --> 00:18:31,400
same address is pointing to this variable also. Actually,

344
00:18:31,400 --> 00:18:33,100
this is for your original variable.

345
00:18:33,700 --> 00:18:35,900
Same address is pointing to this variable.

346
00:18:37,000 --> 00:18:41,000
But if you do 'copy', other memory location will be created.

347
00:18:41,100 --> 00:18:43,700
That address memory location will be point out to this variable.

348
00:18:43,700 --> 00:18:45,000
That is the use of 'copy'.

349
00:18:45,000 --> 00:18:48,200
[no audio]

350
00:18:48,200 --> 00:18:49,800
Right. Let me prove that.

351
00:18:51,000 --> 00:18:57,700
'print(id())', 'id' means, address location, right, 'my_list', and then

352
00:18:57,700 --> 00:19:04,600
let me take 'id(my_new_list)'. Then I am printing the

353
00:19:04,600 --> 00:19:16,800
last one separately, 'print(id(my_one_list))'. Just see the

354
00:19:16,800 --> 00:19:21,100
output. See for these two you're getting same 'id' locations,

355
00:19:21,200 --> 00:19:24,700
but for last one different. So that is the use of 'copy' operation.

356
00:19:26,100 --> 00:19:27,600
Right. Fine.

357
00:19:27,700 --> 00:19:31,000
So this is about 'copy', or assigning one list to other list.

358
00:19:31,500 --> 00:19:35,500
So there are two ways - one is assigning same memory location

359
00:19:35,500 --> 00:19:39,300
address, referring to same memory location, or create a new

360
00:19:39,300 --> 00:19:41,100
memory location and store the result,

361
00:19:41,100 --> 00:19:43,400
then that result we are assigning to different variable.

362
00:19:44,700 --> 00:19:47,000
That's fine. Now, let me go with,

363
00:19:47,000 --> 00:19:50,700
[no audio]

364
00:19:50,700 --> 00:19:56,500
I will go with now 'append'. 'append' is nothing but, see as of

365
00:19:56,500 --> 00:19:57,500
now what is your data?

366
00:19:57,900 --> 00:19:59,500
See that. 'print(my_list)'.

367
00:20:02,000 --> 00:20:04,100
[3, 5, 2, 7, 3, 8, 9], right?

368
00:20:05,100 --> 00:20:10,500
Now, I want to add some new data at the end of my list.

369
00:20:10,800 --> 00:20:13,400
That is nothing but generally, that operation is called generally

370
00:20:13,400 --> 00:20:16,800
appending. So appending is nothing but for existing information

371
00:20:16,800 --> 00:20:19,100
at the end you are adding something that is the meaning of

372
00:20:19,100 --> 00:20:21,900
appending. Same thing is applicable with your list

373
00:20:21,900 --> 00:20:27,000
also. Let's say 'my_list.append'. So guys for this operation also

374
00:20:27,000 --> 00:20:29,500
I'm not using 'print' statement because this is going to

375
00:20:29,500 --> 00:20:32,600
modify your data. Whenever if you are modifying your list

376
00:20:33,200 --> 00:20:34,200
that operation

377
00:20:34,500 --> 00:20:35,800
don't do with print.

378
00:20:36,900 --> 00:20:40,700
'my_list.append', I want to append some number 56.

379
00:20:41,100 --> 00:20:44,000
So after appending just observe the result.

380
00:20:44,000 --> 00:20:46,700
[no audio]

381
00:20:46,700 --> 00:20:51,500
56 added at the end, but I want to add this 56 somewhere

382
00:20:51,600 --> 00:20:52,900
between 3 and 5,

383
00:20:54,300 --> 00:20:58,800
or between 2 and 7, anywhere. In case if I insert between

384
00:20:58,800 --> 00:21:03,300
3 and 5, after inserting my number, whatever I am going to

385
00:21:03,300 --> 00:21:08,300
insert, that inserted data index will be 1 because 3 is 0,

386
00:21:08,300 --> 00:21:11,300
5 is 1 as of now. But if I insert between this you are

387
00:21:11,300 --> 00:21:16,000
getting, right. So see that, 'my_list.

388
00:21:17,200 --> 00:21:18,200
insert',

389
00:21:18,200 --> 00:21:22,200
[no audio]

390
00:21:22,200 --> 00:21:24,200
let's say index

391
00:21:25,900 --> 00:21:30,700
1, value 45. Then after inserting see your list.

392
00:21:30,700 --> 00:21:35,600
[no audio]

393
00:21:35,600 --> 00:21:37,800
See, between 3 and 5 you inserted

394
00:21:37,800 --> 00:21:40,300
your data based on index position.

395
00:21:41,000 --> 00:21:42,800
'append' is going to add at the end,

396
00:21:43,000 --> 00:21:46,600
but 'insert' is going to add based on index position where

397
00:21:46,600 --> 00:21:47,600
you want to insert.

398
00:21:48,200 --> 00:21:52,700
So 1, index 1, I should have a value called 45. Then see that,

399
00:21:52,700 --> 00:21:54,900
3, 45, 5.

400
00:21:54,900 --> 00:22:00,200
So 3 is 0, 45 is 1, right. So 'append', 'insert' are used to add

401
00:22:00,200 --> 00:22:03,800
your data to your list. 'append' is going to add your data at

402
00:22:03,800 --> 00:22:05,300
the end, 'insert' is going to add

403
00:22:05,500 --> 00:22:09,100
data to your existing list based on your required index position.

404
00:22:10,900 --> 00:22:12,200
Right. Fine.

405
00:22:12,400 --> 00:22:15,400
Now you have one more thing called 'extend' operation. See that

406
00:22:15,400 --> 00:22:18,000
somewhere you have 'extend'. 'extend',

407
00:22:18,000 --> 00:22:19,900
[no audio]

408
00:22:19,900 --> 00:22:22,200
right. So we have seen 'insert',

409
00:22:22,800 --> 00:22:24,000
Let me go with 'extend'.

410
00:22:24,000 --> 00:22:26,600
[no audio]

411
00:22:26,600 --> 00:22:27,300
So suppose

412
00:22:27,300 --> 00:22:29,400
I have one new list called

413
00:22:29,400 --> 00:22:32,000
[no audio]

414
00:22:32,000 --> 00:22:38,200
5 and 6. If I simply do 'my_list.append

415
00:22:39,800 --> 00:22:44,800
(my_new_list)', and after this operation, just observe your output,

416
00:22:44,800 --> 00:22:46,200
how you are getting your list.

417
00:22:47,700 --> 00:22:51,100
'append' means at the end you are adding your 5, 6 data.

418
00:22:52,100 --> 00:22:56,800
As the list of, see last value is also one list, you're

419
00:22:56,800 --> 00:22:57,700
getting square brackets,

420
00:22:57,700 --> 00:23:02,700
no, but instead of 'append', instead of 'append' if I take 'extend',

421
00:23:02,700 --> 00:23:04,700
[no audio]

422
00:23:04,700 --> 00:23:07,200
now see the result. You don't have the square brackets. Directly

423
00:23:07,200 --> 00:23:10,400
it is normal data. You are adding your list as a normal

424
00:23:10,400 --> 00:23:13,800
data into your existing list. That's it.

425
00:23:13,800 --> 00:23:16,800
[no audio]

426
00:23:16,800 --> 00:23:20,200
So that is all about your 'extend'.

427
00:23:20,200 --> 00:23:25,200
[no audio]

428
00:23:25,200 --> 00:23:26,200
Fine.

429
00:23:27,000 --> 00:23:31,500
So we're done with 'append', 'clear', 'copy', 'count', 'extend', 'index' also

430
00:23:31,500 --> 00:23:36,700
done, 'insert' done, now 'pop' and 'remove'. 'remove' is going to remove

431
00:23:36,700 --> 00:23:40,100
your value directly. 'pop' is going to remove based on index

432
00:23:40,100 --> 00:23:45,200
position. Let's say I am doing first thing your list,

433
00:23:45,200 --> 00:23:46,500
so as of now what is your list?

434
00:23:46,500 --> 00:23:47,200
Let me check it.

435
00:23:47,200 --> 00:23:49,700
[no audio]

436
00:23:49,700 --> 00:23:52,100
So this is your list, right?

437
00:23:53,400 --> 00:23:57,100
So I am doing some operation called 'my_list.remove',

438
00:23:57,800 --> 00:23:59,700
let's say a value called 10.

439
00:23:59,700 --> 00:24:01,700
[no audio]

440
00:24:01,700 --> 00:24:04,200
Right. After this I am trying to print. Actually you don't

441
00:24:04,200 --> 00:24:05,700
have a number 10 in your list.

442
00:24:06,000 --> 00:24:08,000
But if I do that, see that, what you are getting.

443
00:24:09,300 --> 00:24:12,500
x is not in the list. That means whatever the value you are

444
00:24:12,500 --> 00:24:15,000
removing that is not in the list, right?

445
00:24:15,100 --> 00:24:17,700
So in your real time whenever if you are doing this operation

446
00:24:17,700 --> 00:24:19,300
before that you will take some condition,

447
00:24:19,300 --> 00:24:21,000
'if' condition, then we will remove it.

448
00:24:21,100 --> 00:24:23,300
If it is there then only we will remove. If it is not there

449
00:24:23,300 --> 00:24:24,200
we don't remove it.

450
00:24:25,300 --> 00:24:29,500
In case whatever the value you are having that value I want to remove,

451
00:24:30,600 --> 00:24:33,200
right. So what are the values we are having? 3, 5, 2, 7.

452
00:24:33,200 --> 00:24:34,400
Let me take 8.

453
00:24:34,400 --> 00:24:36,400
[no audio]

454
00:24:36,400 --> 00:24:40,100
Now see the output. After remove operation you are removing number 8.

455
00:24:41,700 --> 00:24:45,200
Right. Now, let me comment 'remove'.

456
00:24:45,200 --> 00:24:49,000
[no audio]

457
00:24:49,000 --> 00:24:52,200
Now what I am doing is, you have 'pop' operation.

458
00:24:54,100 --> 00:24:57,300
First, let me do this, 'my_list.pop'.

459
00:24:57,800 --> 00:24:59,800
I am not giving any index position.

460
00:24:59,800 --> 00:25:02,000
First see the output what it is doing.

461
00:25:02,000 --> 00:25:03,900
[no audio]

462
00:25:03,900 --> 00:25:07,400
So before 'pop' this is the data, after 'pop' this is the data.

463
00:25:09,000 --> 00:25:13,000
Right. So by default 'pop' will remove the last data.

464
00:25:14,100 --> 00:25:17,400
If you give index position, let's say I am giving index 2, index

465
00:25:17,400 --> 00:25:22,600
2, or let's say index 0, now see the output. If you provide

466
00:25:22,600 --> 00:25:24,900
index position it will remove that data.

467
00:25:25,200 --> 00:25:28,000
If you don't provide, by default it will remove the last

468
00:25:28,000 --> 00:25:33,700
data, last index value, right. And one important point

469
00:25:33,700 --> 00:25:35,600
is there with your 'pop' operation.

470
00:25:35,600 --> 00:25:38,900
[no audio]

471
00:25:38,900 --> 00:25:40,100
Let me show you that.

472
00:25:41,300 --> 00:25:45,400
So as of now, what is your list? This is your list, right. 'print'.

473
00:25:46,800 --> 00:25:50,800
Actually, your 'pop' is modifying your data, right?

474
00:25:50,800 --> 00:25:54,300
That's why actually you should not use your direct operation,

475
00:25:54,300 --> 00:25:58,300
'my_list.pop' into print. But there is a special property

476
00:25:58,300 --> 00:26:03,400
with your 'pop', that is, your 'pop' will remove your data at the

477
00:26:03,400 --> 00:26:05,700
same time it also gives what is the data

478
00:26:05,700 --> 00:26:09,900
it is going to remove. That's why I can use it in my 'print' statement.

479
00:26:09,900 --> 00:26:12,700
[no audio]

480
00:26:12,700 --> 00:26:16,500
See the output. It is removing 9, that is it is

481
00:26:16,500 --> 00:26:18,200
giving. At the same time

482
00:26:18,200 --> 00:26:20,300
that data is removed from your list.

483
00:26:20,400 --> 00:26:21,900
That's why, see the output.

484
00:26:23,100 --> 00:26:27,200
So only 'pop' operation will give

485
00:26:27,200 --> 00:26:31,000
the data what it is removing, at the same time

486
00:26:31,000 --> 00:26:33,100
it will remove in your original data.

487
00:26:34,600 --> 00:26:37,400
Right. So that is the use of 'pop'.

488
00:26:38,500 --> 00:26:41,500
Now let me comment this. Now we have

489
00:26:41,500 --> 00:26:44,300
[no audio]

490
00:26:44,300 --> 00:26:48,100
'reverse' and 'sort'. Let me do with 'sort' first.

491
00:26:48,100 --> 00:26:50,200
[no audio]

492
00:26:50,200 --> 00:26:53,600
Otherwise, as of now what is your data, guys?

493
00:26:53,700 --> 00:26:54,900
See that output once.

494
00:26:54,900 --> 00:26:55,900
This is your data.

495
00:26:55,900 --> 00:26:57,800
[no audio]

496
00:26:57,800 --> 00:27:00,600
Okay. Now I am doing something called

497
00:27:00,600 --> 00:27:03,200
[no audio]

498
00:27:03,200 --> 00:27:04,700
'my_list.,

499
00:27:04,800 --> 00:27:06,000
let me do 'reverse' first,

500
00:27:06,000 --> 00:27:08,500
[no audio]

501
00:27:08,500 --> 00:27:11,300
and after 'reverse' see what is your list is there?

502
00:27:11,300 --> 00:27:13,600
[no audio]

503
00:27:13,600 --> 00:27:16,900
See before 'reverse' operation, and after 'reverse' operation.

504
00:27:17,100 --> 00:27:19,500
So it is like, you know mirror image of your data.

505
00:27:20,700 --> 00:27:24,400
Right. Now, let me comment your 'reverse' operation, and I am

506
00:27:24,400 --> 00:27:27,600
going to do 'my_list.sort' operation.

507
00:27:28,400 --> 00:27:32,700
So 'sort' is nothing but, it is going to arrange your data

508
00:27:32,700 --> 00:27:35,100
in ascending order. See that.

509
00:27:35,100 --> 00:27:37,700
[no audio]

510
00:27:37,700 --> 00:27:40,500
Now if you want to get data in

511
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descending order, first perform 'sort', and then do your 'reverse' operation.

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Now see the output, descending order. Or else

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you can also use shortcut as 'my_list.sort', here

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you can write 'reverse=True'.

516
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So instead of performing 'reverse' separately you can also

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do in this way. Now see the result.

518
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Yes, you are getting in the reverse order, right.

519
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So guys, these all are the operations on your list,

520
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okay. So in next video, we'll discuss about tuple.

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522
00:28:15,700 --> 00:28:17,500
Right. Okay guys,

523
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thank you for watching this video.

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