How to sort a list of dicts with numeric and alphabetic strings?

Question

I need help to sort my list of dicts.

my_list = [{'id': 1, 'code': '2'}, {'id': 2, 'code': 'b'}, {'id': 3, 'code': '1'}, {'id': 4, 'code': '10'}, {'id': 5, 'code': 'a'}]

import operator
my_list.sort(key=operator.itemgetter('code'))

Result:

[{'id': 3, 'code': '1'}, {'id': 4, 'code': '10'}, {'id': 1, 'code': '2'}, {'id': 5, 'code': 'a'}, {'id': 2, 'code': 'b'}]

I want to sort the list like that:

[{'id': 3, 'code': '1'}, {'id': 1, 'code': '2'}, {'id': 4, 'code': '10'}, {'id': 5, 'code': 'a'}, {'id': 2, 'code': 'b'}]

I didn't see answer to sort it.

Answer 1

You need to cast the numerical strings to int (or float ) for the sorting not to be lexicographic on the numerical strings. A simple way is defining a custom sorting function as:

def custom_sort(x):
    try:
        return 0, float(x)
    except ValueError:
        return 1, x

my_list.sort(key= lambda x: custom_sort(x['code']))

---

print(my_list)

[{'id': 3, 'code': '1'},
 {'id': 1, 'code': '2'},
 {'id': 4, 'code': '10'},
 {'id': 5, 'code': 'a'},
 {'id': 2, 'code': 'b'}]