你如何按字母顺序排列字典？

Question

I have a dictionary pickled in python as:

my_dictionary = {'abc': '123', 'def': '456', 'ABC': '123', 'Abc': '123', 'DEF': '456', 'Def': '456'}

What to call a function that sorts the dictionary out as:

my_dictionary = {'abc':'123', 'Abc':'123', 'ABC':'123', 'def':'456', 'Def':'456', 'DEF':'456'}

Currently I unpickle the dictionary and copy the dictionary to a list of tuples. Then sort the tuples and dump the dictionary back in.

Specifically, is there a way to sort the dictionary by its keys as (abc, Abc, ABC)? Or sort it as a list tuples (abc, Abc, ABC)?

Thanks

Answer 1

As long as you are using Python3.7+ (technically 3.6+), where dictionaries are in insertion order, you can make a new dictionary which will be in sorted order.

my_dictionary = {'abc':'123', 'def':'456', 'ABC':'123', 'Abc':'123', 'DEF':'456', 'Def':'456'}
sorted_dict = {key: my_dictionary[key] for key in sorted(my_dictionary.keys())}
print(sorted_dict)

Output:

{
  "ABC": "123",
  "Abc": "123",
  "DEF": "456",
  "Def": "456",
  "abc": "123",
  "def": "456"
}

-- Edit --

Alternatively you can use items() with a sort key such as:

my_dictionary = {'abc':'123', 'def':'456', 'ABC':'123', 'Abc':'123', 'DEF':'456', 'Def':'456'}
sorted_dict = dict(sorted(my_dictionary.items(), key=lambda x: x[0]))
print(sorted_dict)

Answer 2

You can write your own customed sort function ie:

def test(a,b):
    x, y = a.upper(), b.upper()
    if x < y: return True
    elif x == y:
        if a>b: return True

def mysort(x):
    n = len(x)
    for i in range(n-1):
        mn = x[i]
        ind = i
        for j in range(i,n):
            if test(x[j],mn): 
                mn = x[j]
                ind = j
        x[ind], x[i] = x[i], mn
    return x

then you could run:

{i:my_dictionary[i] for i in mysort(list(my_dictionary.keys()))}
Out[58]: 
{'abc': '123',
 'Abc': '123',
 'ABC': '123',
 'def': '456',
 'Def': '456',
 'DEF': '456'}

of course you could try

 mysort(['ABC','acD','Abc','abc'])

Just note that this an implementation of the insertion sort You can implement any sorting algorithm that best suits your case. Though this is not too efficient for large lists