Python programming about list

Question

In this program I want to remove the duplicate values from the list. This is what i wrote:

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

def loop():
    for a in range(len(list)-1):
        for b in range(a+1,len(list)):
            if list[a] == list[b]:
                del list[a]
    print(list)  
loop()

But, it's giving me this error:

Can you help me?

It's because you are deleting items while you are looping through the list, create a new list with only the items you want. If you want to remove duplicates you can just do `list(set(listName))` — Keatinge, Nov 13 '16 at 07:28

score 0 · Answer 1 · answered Nov 13 '16 at 07:31

0

If you have numpy then you can do (I renamed your list to l to avoid ambiguity):

import numpy as np 
l = [1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89]
l_no_duplicates = list( np.unique(l) )

answered Nov 13 '16 at 07:31

Angus Williams

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score 0 · Answer 2 · answered Nov 13 '16 at 07:31

0

The common approach to get a unique collection of items is to use a set. Sets are unordered collections of distinct objects.

list = [1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89]
newList = list(set(list))

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

answered Nov 13 '16 at 07:31

anati

264
2
13

MiniGunnR · Answer 3 · 2016-11-13T07:36:05.540

-1

Do something like the following:

create new_list
for item in list:
    if item not in new_list:
        add item to new_list
list = new_list

In Python:

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

print list
new_list = []
for item in list:
    if item not in new_list:
        new_list.append(item)
list = new_list
print list

Now run python filename.py and you will see the difference between two lists.

edited Nov 13 '16 at 07:36

answered Nov 13 '16 at 07:29

MiniGunnR

5,590
8
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66

Python programming about list

3 Answers3