Hey guys. I am having problem on my code on python

Question

I am having problem on how to code this one:

def letter_count(word):
    ans = {}
    word = ''.join(j for j in word if j.isalpha()).lower()
    for j in word:
        keys = ans.keys()
        if j not in keys:
            ans [j] = 1
        else:
            ans [j] += 1
    return ans

print(letter_count(word = "Hello_world!"))

I keep getting this one

{'h': 1, 'e': 1, 'l': 3, 'o': 2, 'w': 1, 'r': 1, 'd': 1}

But I want to make my output into

output = [
            ("d", 1),
            ("e", 1),
            ("h", 1),
            ("l", 3),
            ("o", 2),
            ("r", 1),
            ("w", 1)
        ]

Answer 1

Use return list(ans.items()) instead of return ans. This how to turn a dict into a list of tuples like you wanted.

With this change, the output is:

[('h', 1), ('e', 1), ('l', 3), ('o', 2), ('w', 1), ('r', 1), ('d', 1)]

Answer 2

Replace return ans with

[(k, v) for k, v in ans.items()]

Answer 3

This would be a good case for utilising defaultdict as follows:

from collections import defaultdict
def letter_count(word):
    d = defaultdict(int)
    for c in word.lower():
        if c.isalpha():
            d[c] += 1
    return [(k, v) for k, v in d.items()]
print(letter_count(word = "Hello_world!"))

Output:

[('h', 1), ('e', 1), ('l', 3), ('o', 2), ('w', 1), ('r', 1), ('d', 1)]

Answer 4

Use set to remove the repeated elements from the data. It will be needed as a sequence of unique characters used to count. To avoid discrimination between upper and lower case characters I used the casefold method.

text = "Hello_worlDd!"

# get unique characters
chars = set(char for char in text.casefold() if char.isalpha())

# count the characters in the text
text_as_chars = tuple(text.casefold())
stats = [(char, text_as_chars.count(char)) for char in chars]

print(stats)

Output

[('l', 3), ('h', 1), ('o', 2), ('w', 1), ('e', 1), ('r', 1), ('d', 2)]