List of letter occurences Python-CodePudding

I have a coding assignment where I need to create a program that checks for the number of times a dictionary of names have the letters R, M, A, K and C. So in this case I have this dictionary:

dict = {"Renata", "Maciek", "Marek", "Karolina", "Marcel}

I need to create a loop that checks for all of those letters in all of the names in the dictionary one by one. Once it is done, it needs to put the results in a list and return the list at the end of the program. So the result will look like

R - 4 M - 2 A - 3. (numbers are just to give an example) K - 5 C - 6

This is what I have so far:

names = {"Renata", "Marek", "Maciek", "Karolina", "Marcel"}

letter = ['R', 'M', 'A', 'K', 'C'] 

counter = 0 

for letter in names:

    print("R =", names.count("R"))
    print("M =", names.count("M"))
    print("A =", names.count("A"))
    print("K =", names.count("K"))
    print("C = ", names.count("C"))

I am very new to Python as you can see so I would greatly appreciate some input or help. Please show the changes that you make to the code. Thank you in advance

CodePudding user response：

For example, this way:

names = {"Renata", "Marek", "Maciek", "Karolina", "Marcel"}
names_concatenated = "".join(names).upper()
letters = ['R', 'M', 'A', 'K', 'C']

for letter in letters:
    print(f"Letter '{letter} occurrences count in `names`: "
          f"{names_concatenated.count(letter)}")

Here we have:

Letter 'R' occurrences count in `names`: 4
Letter 'M' occurrences count in `names`: 3
Letter 'A' occurrences count in `names`: 7
Letter 'K' occurrences count in `names`: 3
Letter 'C' occurrences count in `names`: 2

CodePudding user response：

The Counter subclass in the inbuilt collections library is very convenient for this sort of thing. I would implement it like this:

from collections import Counter

names = {"Renata", "Marek", "Maciek", "Karolina", "Marcel"}
all_letters = ''.join(names).upper()

counter = Counter(all_letters)
for l in ['R', 'M', 'A', 'K', 'C']:
    print(l, ":", counter[l])

Output:

R : 4
M : 3
A : 7
K : 3
C : 2

CodePudding user response：

Here's one approach:

names = {"Renata", "Marek", "Maciek", "Karolina", "Marcel"}

# Create a dictionary that maps each letter that we're tracking to a frequency counter.
letter_counters = {'R': 0, 'M': 0, 'A': 0, 'K': 0, 'C': 0}

# Go through the set of names, one at a time, and add the frequency of each letter that we're tracking to our counters.
# .upper() is used to make our counting case-insensitive.
for name in names:
    for letter in letter_counters:
        letter_counters[letter]  = name.upper().count(letter)

# Transform the dictionary into a list. (This could be made more concise using a list comprehension, though this is not immediately relevant to the question.)
result = []
for letter in letter_counters:
   result.append([letter, letter_counters[letter])