How to flatten a list of tuples and remove the duplicates?

Question

I'm trying to remove the duplicates out of tuples in a list and add them in a new list with out duplicates,

I tried to make two loops but and check for duplicates or sets but the problem there's three tuples

can anyone help me, I'm stuck here

example

[(2, 5), (3, 5), (2, 5)]

Output

[2, 3, 5]

Answer 1

If order isn't important, you can make a set , add each element of each tuple to the set, and the set is your result.

s = set()
for tup in lst:
    for el in tup:
        s.add(el)
# or use a set comprehension:
# # s = {el for tup in lst for el in tup}

If order IS important, you can do mostly the same, but also have a result list to add to.

s = set()
result = []
for tup in lst:
    for el in tup:
        if el not in s:
            s.add(el)
            result.append(el)

Answer 2

You can use set comprehension:

lst = [(2, 5), (3, 5), (2, 5)]
{e for l in lst for e in l}

Answer 3

you need to iter through each tuple and then each element of tuple. before append just check if the element is in list:

a = [(2, 5), (3, 5), (2, 5)]
b = []
for i in a:
    for j in i:
        if j not in b:
           b.append(j)
print b

After running above code I got this output:

[2, 5, 3]

Answer 4

An easy way to do so is using numpy ravel, and then set:

import numpy as np
lst = [(2, 5), (3, 5), (2, 5)]
res = list(set(np.ravel(a)))

gives:

[2, 3, 5]

Answer to Apero's comment:

if you don't want to use numpy, you would be able to flatten the list with:

lst = [(2,5), (3,5), (2,5)]
tmp = []
for i in lst:
    for j in i:
        tmp.append(j)

res = set(tmp)
print res

which gives:

[2, 3, 5]