Sorting tuples by element value in Python

Question

I need to sort a list of tuples in Python by a specific tuple element, let's say it's the second element in this case. I tried

sorted(tupList, key = lambda tup: tup[1])

I have also tried

sorted(tupList, key = itemgetter(1))
'''i imported itemgetter, attrgetter, methodcaller from operator'''

but the list was returned the same both times. I checked

sorting tuples in python with a custom key

sort tuples in lists in python

https://wiki.python.org/moin/HowTo/Sorting

Answer 1

I'm guessing you're calling sorted but not assigning the result anywhere. Something like:

tupList = [(2,16), (4, 42), (3, 23)]
sorted(tupList, key = lambda tup: tup[1])
print(tupList)

sorted creates a new sorted list, rather than modifying the original one. Try:

tupList = [(2,16), (4, 42), (3, 23)]
tupList = sorted(tupList, key = lambda tup: tup[1])
print(tupList)

Or:

tupList = [(2,16), (4, 42), (3, 23)]
tupList.sort(key = lambda tup: tup[1])
print(tupList)