Can you sort dictionary keys alphabetically into a list variable and print with a specific output?

Question

What below gives me is an alphabetical list of my keys and values in the correct format, but is there a way to iterate the alphabetized keys and values into a list variable and print the list out so that the output looks exactly the same as the output give below? I have reviewed some similar questions; I am still left unsure if sort() actually creates a list variable that can be manipulated further down the line if I wanted.

def readFile(fileName):
    fileIn = open(fileName, "r")
    letterFrequency = {}
    for line in fileIn:                             
        line = line.strip()
        for letter in line:
            if letter.isalpha() is True:         
                if letter not in letterFrequency:      
                    letterFrequency[letter.lower()] = 1
                else:                                  
                    letterFrequency[letter.lower()] += 1
            else:
                pass
fileIn.close()
return letterFrequency

def main():
    fileName = input("What is the name of the file? ")
    letterDict = readFile(fileName)      
    for letter in sorted(letterDict):
        print(letter, letterDict[letter])



main()

OUTPUT FOR ABOVE:

a 102
b 11
c 31
d 58
e 165
f 27
g 2
h 80 
i 17
k 3
l 42
m 13
n 63
o 93
p 15
q 1
r 79
s 44
t 60
u 21
v 24
w 21
y 10

You can sort the items in `letterDict`. e.g. `sorted(letterDict.items())` This way you have a list of tuples sorted alphabetically and can iterate the results with a `for key, value in result: ...` — Oluwafemi Sule, Oct 17 '18 at 00:16
Why do you need the `list` specifically? What is your current solution lacking? I'm not clear on what problem you actually have that necessitates a solution of any kind; sure, iterating `sorted(d.items())` would be somewhat more efficient (slightly worse on memory, better on runtime most likely, and easier to read if unpacked to meaningful names), but either way works. — ShadowRanger, Oct 17 '18 at 00:55
@ShadowRanger Due to being new to Python, I have many questions that may/may not make sense. This is out of pure curiosity--learning what I can/cannot do. Your comments are helpful in this respect. — PattyWatty27, Oct 17 '18 at 07:28

kungphu · Answer 1 · 2018-10-18T02:08:58.827

1

d = {"a": 5, "n": 2, "z": 1, "c": 3, "b": 0}

t = tuple((k, d[k]) for k in sorted(d.keys()))
print(t)
# (('a', 5), ('b', 0), ('c', 3), ('n', 2), ('z', 1))

Note that you don't need the tuple() call here; without it you'll get a (more efficient) generator. It's there in this example to make it easy to see the result.

edited Oct 18 '18 at 02:08

answered Oct 17 '18 at 00:20

kungphu

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score 0 · Answer 2 · answered Oct 17 '18 at 07:37

I have created a list, sorted the list, and printed from the dictionary, pulling the key names from the sorted list. Now, with respect to efficiency, necessity, etc.--that is beyond my scope of knowledge.

This is how I resolved my question:

def readFile(fileName):
    fileIn = open(fileName, "r")
    letterFrequency = {}
    for line in fileIn:                                         
        line = line.strip()
        for letter in line:
            if letter.isalpha() == True:                        
                if letter.lower() not in letterFrequency:       
                    letterFrequency[letter.lower()] = 1
                else:                                          
                    letterFrequency[letter.lower()] += 1
            else:
                pass
    fileIn.close()
    return letterFrequency


def sortKeys(dictionary):
    listNew = list(dictionary)
    listNew.sort()
    return listNew


def main():
    fileName = input("What is the name of the file you are trying to process? ")
    letterDict = readFile(fileName)    
    listNew = sortKeys(letterDict)
    for key in listNew:
        print(key, letterDict[key])


main()

Your `sortKeys` function is, aside from not supporting `key` and `reverse` arguments, an *exact* duplicate of how `sorted` works (all `sorted` does is convert input to a new `list`, call `.sort()` on it with provided arguments, then return the newly sorted `list`). — ShadowRanger, Oct 17 '18 at 10:55

Can you sort dictionary keys alphabetically into a list variable and print with a specific output?

2 Answers2