List remove duplicates using list comprehension in Python

Asked Dec 09 '18 at 15:38

Active Dec 09 '18 at 18:38

Viewed 60 times

I'm new to Python and i'm trying to remove duplicates from a simple list by using list comprehension (without using sets).

a = [1, 1, 2, 2, 2, 3, 5, 8, 13, 21, 34, 55, 89]

i can do it by doing this:

z=[]
for x in a:
   if(z.count(x)==0):
     z.append(x)

but with using list comprehension i don't know why it doesn't work:

z=[]
z=[x for x in a if z.count(x)==0]

what's the error there ?

edited Dec 09 '18 at 18:38

asked Dec 09 '18 at 15:38

hamza saber

1

Because your counter can't have `0` entries? If it exists in the list, it must, at least, have a count of `1` – roganjosh Dec 09 '18 at 15:40
@roganjosh This part makes sense. See the non-list comprehension version – DeepSpace Dec 09 '18 at 15:42
Check [this](https://stackoverflow.com/a/24582741/4932316) out – Sheldore Dec 09 '18 at 15:43
`z` is not defined within the scope of the list. – Mehdi Dec 09 '18 at 15:45
1

One solution using list comprehension is `z = [i for n, i in enumerate(a) if i not in a[:n]]` as per the link I posted above – Sheldore Dec 09 '18 at 15:47
I've found the solution [Here](https://stackoverflow.com/a/52067330/9727794). Thank you guys for everything – hamza saber Dec 09 '18 at 18:50

0 Answers0