How would I convert a dictionary into a multi-dimensional list sorted by value?-CodePudding

I'm currently working on a small project (I'm relatively new to python) in which I have a dictionary of items (as an example):

dic = {
    'ab': 'a',
    'ac': 'a',
    'bc': 'b',
    'bd': 'b',
    'cd': 'c',
    'ce': 'c'
}

And would like to convert it into a list with each initial index being correlated to one of the values

sorted_lst[0][1] = ab
sorted_lst[2][1] = ce

and so forth. How would I go about doing this? Would it be easier to start with a sorted list rather than a dictionary?

The reason for doing so, is that I would like to print out columnal lists of guesses in which their assignment is derived from the initial letter of the guess. ie. something like:

ab  bc  cd
ac  bd  ce

So that the user can see their guesses in a more appealing way rather than just as an alphabetized list.

CodePudding user response：

Looks like you could use a defaultdict to transform your data to 2D:

from collections import defaultdict

d = defaultdict(list)

for k,v in dic.items():
    d[v].append(k)
    
sorted_lst = list(d.values())
# or to ensure sorting of the first level:
# sorted_lst = [d[k] for k in sorted(d)]

sorted_lst[0][1]
# ac

sorted_lst[2][1]
# ce

output: [['ab', 'ac'], ['bc', 'bd'], ['cd', 'ce']]

CodePudding user response：

Here is one way to do so:

We sort the unique values, then loop through each one and group the keys into a list.

data = {
    'ab': 'a',
    'ac': 'a',
    'bc': 'b',
    'bd': 'b',
    'cd': 'c',
    'ce': 'c'
}

sorted_data = []
for item in sorted(set(data.values())):
    sorted_data.append([key for key in data.keys() if data[key] == item])
# sorted_data = [['ab', 'ac'], ['bc', 'bd'], ['cd', 'ce']]

You can also use setdefault():

sorted_data = {}
for key, item in data.items():
    sorted_data.setdefault(item, []).append(key)
sorted_data = list(sorted_data.values())

To print the values you can then loop over each item:

for i in range(len(sorted_data[0])):
    for j in range(len(sorted_data)):
        print(sorted_data[j][i], end=" ")
    print("")

output:

ab bc cd 
ac bd ce