Making a list in Python is simple: x = [1,2,3,4]
Now let us see how we can work with them.
First thing to understand is that a list is indexed. Each item in the list is given a number that tells you its position in the list.
It is important to note that Python is a 0 index language. This means indexes begin at 0 not 1. So the first item in the list, is found by calling: x
Note that x returns an error. Since there are 4 items in the list, the indexes go 0,1,2,3. Index 4 is out of range.
Another interesting point to understand about indexes is that you can use a negative index. x[-2] returns Duck
Use a “:” to return a range of items from a list: x[start:end]. If you leave out the start or end number, the index starts or ends at the start or end of the list
Update Values in a List
If you want to change a value in a list, just assign it a new value like you would with a regular variable.
If you want to add an item to then end of a list, you can use the Append() function
To delete a item from a list, use the Del command.
Remove works like Del, except instead of using index values, Remove() uses the values stored in the list.
Pop() and Insert()
Pop() simply returns the last item from a list
Insert() lets you add a item to a list, but it also lets you choose what position in the list to add it.
Len() returns a count of the number of items in a list.
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