Lists |Section 1| Celestial Warrior

1 year ago
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udemy python pythercourse skills skillelearning Andrewtate Hamza Millionare Billionaire ElonMusk

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Great, now let's look at lists, so in the

previous lecture we were looking at

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strings and indexing and splitting

strings and I will be working with lists

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which are very similar to strings. They

are similar because they are both

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referred to as sequences, so there are

sequences of items. The difference is

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that, let me open Python, and so the

difference is that the string is made of

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other strings so it can contain only

strings of characters or strings.

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whatever you like to call it, however

lists can contain various other data

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types, let's say H a letter, a number, and

also a string. So this is a string the

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first one, this is a number, an integer.

This is also string with multiple

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characters and that is a list, so for

this you want to use square brackets to

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create a list. Execute and yeah you can

call it and so this is a list of three

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items and you can also store other

objects in a list but we'll cover other

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objects in later sections, you know we

have table of objects with lots of data.

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You may store files in a list you may

store widgets of a graphical user

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interface that you are building and so

on, so these are very useful and lists also

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have indexing and you can split lists,

you can extract items and so on. So the

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good news is that lists have the

same indexing system as strings and so

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you've learned that in the previous

lecture and you can go ahead and apply

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that system not, so let's extract number 2.

That would have an index of one.

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Execute that and yeah you get 2 there. If you

check the type you'll see that's an integer.

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So every item of a list has its own

data type, even also access more than

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white one item of a list. Let's say

you want the first two items. You do 0 1 2, so

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like that or 0 to 2 whatever you like.

That will produce another list so the

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type of this split is a list. The type of

the split of a string is a string, so S

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for the string here, C for the list.

Lists now have methods associated with

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them just like strings do and so you can

check what methods you have available

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there by just doing a dir list.

So this a the blueprint you can use

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lists, you can pass empty square brackets

in there, it's the same thing and then

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you can use help to look at each of

these methods, so these are the methods.

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Without the underscore and let's look at

the append method, so to apply methode

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you do c the dot notation append and here

on that 3. What that does, it adds

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another item to the end of the list,

So it appends an item to the

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list and you can explore the other

methods if you like so let's say help.

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Remove like that and you'll see how to

use that remove method, so you do

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c.remove and then you pass the value of

the item that you want to remove, so

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not the index but the value. Let's say we

want to remove 2 and you see that 2

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is now gone from the list so look

at the other methods of the list and try

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to experiment with this and play around

with them access items and split them

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and you'll be good to go then.

Thanks, I'll talk to you later.

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