Extract the list of unique numbers out of a string of numbers

Question

def unique(a):
    for i in a:
        set(a)
set([1,2,3])

print unique([1,1,2,3,2])

Define a function unique(a) that takes a list of numbers a and returns a new list where each element of a occurs only once. The new list should have its elements in the same order as they appear in a. Your function must use a set.

possible duplicate of [How do you remove duplicates from a list in Python whilst preserving order?](http://stackoverflow.com/questions/480214/how-do-you-remove-duplicates-from-a-list-in-python-whilst-preserving-order) — Ben, Oct 12 '14 at 20:07
Welcome to Stack Overflow. It's inconsiderate of other people's time to just dump your question like this. Please take some time to read [the rules](http://stackoverflow.com/help/how-to-ask). — Veedrac, Oct 14 '14 at 21:47

score 1 · Answer 1 · answered Oct 10 '14 at 19:04

1

set is what you want :

>>> a=[1,1,2,2,3,3]
>>> set(a)
set([1, 2, 3])

answered Oct 10 '14 at 19:04

Mazdak

105,000
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@Nick if a is a string passed a argument, just do set(list(a)) – DevLounge Oct 10 '14 at 19:07
see thats what I thought theres so much to learn in python in a semester trying to figure out what do seems to mash into various lectures:P – Nick Bergeron Oct 10 '14 at 19:10
still getting print unique([1,1,2,3,2]) to return none :( – Nick Bergeron Oct 10 '14 at 19:18
sorry karsa i just did add my most recent – Nick Bergeron Oct 10 '14 at 19:39

Extract the list of unique numbers out of a string of numbers

1 Answers1