How do I make this sorting case insensitive?

Question

def sortProfiles(p):
    return sorted(p, key=itemgetter('first_name'))

I have a list with dictionaries. This function allows me to sort them by their first_name. However, it's case-sensitive.

Answer 1

Here's a way:

return sorted(p, key=lambda x: x['first_name'].lower())

Answer 2

>>> from operator import itemgetter
>>> p = [{'fn':'bill'}, {'fn':'Bob'}, {'fn':'bobby'}]
>>> sorted(p, key=itemgetter('fn'))
[{'fn': 'Bob'}, {'fn': 'bill'}, {'fn': 'bobby'}]
>>> sorted(p, key=lambda x: x['fn'].lower())
[{'fn': 'bill'}, {'fn': 'Bob'}, {'fn': 'bobby'}]
>>>

Answer 3

It looks like you want sorted(p, key=lambda d: d['first_name'].lower()).

Answer 4

>>> def my_itemgetter(attr):
        def get_attr(obj):
            return obj.get(attr, "").lower()
        return get_attr

>>> a= [{"a":"dA"},{"a":"ab"},{"a":"Ac"},{"a":"aa"}]
>>> sorted(a, key=my_itemgetter("a"))
[{'a': 'aa'}, {'a': 'ab'}, {'a': 'Ac'}, {'a': 'dA'}]

Answer 5

def sortProfiles(p):
    return sorted(p, key=lambda el: el['first_name'].lower())

Answer 6

If you dislike lambda, you can use a named function as your key-extractor, e.g:

def sortProfiles(p):
    def lowerName(d):
        return d['first_name'].lower()
    return sorted(p, key=lowerName)

The def statement can appear just about anywhere another statement could, including in another function's body. In this case, the choice among a nested def, a lambda, or a separate def outside of sortProfiles, is mostly a matter of style, though the last of these could offer some performance gain.