Set is an unordered data structure

#1

What does it really mean when we say that set is an unordered data structure???
Now if we deduplicate any list by this process in python:
a = [1, 2, 2, 1, 2. 1, 1, 2, 2]
b = list(set(a))
b
In the lecture, it is told that in this process we cant assure whether the order or the indexing of the elements in list b is retained as it was in the list a or not as the set is an unordered dataset.
Will you please elaborate on this in a little bit more detail??

#2

hey @bihan ,
yes sets are unordered.
So actually the thing is , the reason why it is called unordered is that you can access using index , because sets doesn’t maintain any order of the items.
but if you try to print or loop over it , then you will the values in a sorted manner , that is actually a functionality of it.

So , this is the only reason for that.

I hope this helps.

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#3

Do you mean… it can’t be accessed using an index???

#4

yeah, it can’t be accessed.
try it , a[1]

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#5

2021-08-12 00_46_03-Greenshot
2021-08-12 00_46_03-Greenshot1920Ă—1080 161 KB

I tried looping over the set , but why 74 came before 54?

#6

set got sorted when i tried iterating over the set but you see what happend 74 came before 54…why so?

#7

Although it shouldn’t be , but still as it there , so no idea bro about this.

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#8

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