All language subtitles for 2. More Operations with Lists

Let me now make you a bit more familiar with the list data types by showing you what you can do with
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them.
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And you know that already that what you can do with them.
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You can check with dir lists.
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You can ignore the attributes
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that start with double underscore and ends with double underscore.
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They are basically attributes used by Python internally and rarely
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you're going to have to use them.
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So for now you can just ignore them and focus on what you're going to actually use which is this set
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in here.
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Let me open another python shell and I'm going to apply some operations to that's the list in this
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Python shell so we can see what methods we can apply in this window and we can apply the methods in
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this other one here.
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And I don't just want to show you what this does in the dark.
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I want to show you the way you can find out yourself what these things do.
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So always use the help function.
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List, let's try the append method.
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Now I'm going to type the variable,
but you don't have to type all of it.
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Once you have started to type that variable name you can use Tab and that will auto complete the variable
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name, then use the dot notation and append and then two parentheses so inside the parentheses you'll
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see that this takes two arguments.
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Actually it's only one argument.
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It's only the object itself, self is referring to the list itself and object is actually what you want
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to append to that list.
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Let's say you want to append 8.1 like that.
If you check Monday temperatures you'll see that
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it's now has one more item.
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So that is the syntax of append.
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You always ignore self because self is automatically passed as an argument to that method and self
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is basically the actual list itself.
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Let's try another method. Q here to quit, help list clear.
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How does it work?
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Well, in this case you see that it doesn't get any arguments.
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So Monday_temperatures
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dot clear.
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Just like that.
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And what it does it just clears the list it deletes all of its items.
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Let me also try index and leave the rest for you to try.
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So index gets actually a value, a start, and stop and it returns to the index of the value.
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So what is an index?
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Let's try it out. Dot index the value, with value what Python means is one of the values of the list.
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Now since we have a list without values I'm going to recreate the list again like that.
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So now this is our list.
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And lets me try index with parenthesis, and the value let's say 8.8.
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Oh will return 1.
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Why?
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That's because lists have indexing on the background.
Even though we don't see it, each of these items
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is associated with an index.
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The first one has an index of zero.
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The second has an index of one, and the last has an index of 2 in this case and so on.
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Now in this particular case we also see this argument and this other one for the index method.
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However if you don't want to pass those values you can just pass one value.
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So like I did here 8.8.
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That means 8.8 would be the value of this.
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And by default start will be equal to zero.
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A stop will be equal to this value.
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So what is start and stop? Well, when it's 0 like it is by default that means you are looking
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for 8.8.
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Starting from the first item of the list.
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So the interpreter will start the search from the first item,
so the item with index 0 and will look for
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8.8.
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And it will find it and it will tell you that it has an index of 1.
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However, if you want to tell Python to start from the item with index 2 let's say so to start the search
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from here and forward, so to the right of seven point five which happens to not have any more items but
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anyway so you are skipping this part of the list.
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In this case the interpreter will tell you that 8.8 is not in the list with that start
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and you also have the stop which is by default tis big number.
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So if you want to limit the search on the index on the right you can do that too but by default you're
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going to keep that zero.
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And that will tell you that the number has that index.
More about indexing in the next video.