How to sort list in a sequence with python?

July 26, 2022

I have a list of dict like this and here D referes to Day and H refers to Hour. I want to sort the list based on those value. How can I do this ?

First Hour should be sorted and then Days should be sorted.

my_list = [
    {"key1":"123D", "key2":"123D"}, {"key1":"48H", "key2":"48H"},  
    {"key1":None, "key2":"154D"}, {"key1":"122D", "key2":"122D"},
    {"key1":"5D", "key2":"5D"} 
]


sorted_list = sorted(
            my_list,
            key=lambda k: (
                (
                    k["key1"] is None,
                    int(k["key1"][:-1]) if k["key1"] else None,
                ),
                (
                   k["key2"] is None,
                    int(k["key2"][:-1]) if k["key2"] else None,
               ),
            ),
        )

Currently I am getting the result like this:

 [{'key1': '5D', 'key2': '5D'},
 {'key1': '48H', 'key2': '48H'},
 {'key1': '122D', 'key2': '122D'},
 {'key1': '123D', 'key2': '123D'},
 {'key1': None, 'key2': '154D'}]

But what I want is

 [{'key1': '48H', 'key2': '48H'},
 {'key1': '5D', 'key2': '5D'},
 {'key1': '122D', 'key2': '122D'},
 {'key1': '123D', 'key2': '123D'},
 {'key1': None, 'key2': '154D'}]

>Solution :

You need to convert the different representations to a common time unit. Convert the days to hours multiplying by 24:

def key(d):

    k1 = (1, None)
    if d["key1"] is not None:
        v1 = int(d["key1"][:-1]) * (24 if "D" in d["key1"] else 1)
        k1 = (0, v1)

    k2 = (1, None)
    if d["key2"] is not None:
        v2 = int(d["key2"][:-1]) * (24 if "D" in d["key2"] else 1)
        k2 = (0, v2)

    return k1, k2


res = sorted(my_list, key=key)
print(res)

Output

[{'key1': '48H', 'key2': '48H'},
 {'key1': '5D', 'key2': '5D'},
 {'key1': '122D', 'key2': '122D'},
 {'key1': '123D', 'key2': '123D'},
 {'key1': None, 'key2': '154D'}]