Reputation: 1536
I've written a little program to count how many times each vowel appears in a list, but it's not returning the correct count, and I can't see why:
vowels = ['a', 'e', 'i', 'o', 'u']
vowelCounts = [aCount, eCount, iCount, oCount, uCount] = (0,0,0,0,0)
wordlist = ['big', 'cats', 'like', 'really']
for word in wordlist:
for letter in word:
if letter == 'a':
aCount += 1
if letter == 'e':
eCount += 1
if letter == 'i':
iCount += 1
if letter == 'o':
oCount += 1
if letter == 'u':
uCount += 1
for vowel, count in zip(vowels, vowelCounts):
print('"{0}" occurs {1} times.'.format(vowel, count))
The output is
"a" occurs 0 times.
"e" occurs 0 times.
"i" occurs 0 times.
"o" occurs 0 times.
"u" occurs 0 times.
However, if I type aCount
in the Python shell, it gives me 2
, which is correct, so my code has indeed updated the aCount variable and stored it correctly. Why isn't it printing the correct output?
Upvotes: 2
Views: 801
Reputation: 18916
You can also use collections counter (which is the natural go-to function when counting things, it returns a dictionary):
from collections import Counter
vowels = list('aeiou')
wordlist = ['big', 'cats', 'like', 'really']
lettersum = Counter(''.join(wordlist))
print('\n'.join(['"{}" occurs {} time(s).'.format(i,lettersum.get(i,0)) for i in vowels]))
Returns:
"a" occurs 2 time(s).
"e" occurs 2 time(s).
"i" occurs 2 time(s).
"o" occurs 0 time(s).
"u" occurs 0 time(s).
lettersum:
Counter({'l': 3, 'a': 2, 'e': 2, 'i': 2, 'c': 1, 'b': 1,
'g': 1, 'k': 1, 's': 1, 'r': 1, 't': 1, 'y': 1})
Upvotes: 4
Reputation: 1
In addition to what @jpp said simple datatypes like integers are returned by value not by reference so when you assign it to something and change that something it doesn't get affected
a = 10
b = a #b=a=10
b = 11 #b=11, a=10
print a, b
--> 10 11
I'd have made this a comment to his but I need reputation to do that :D
Upvotes: 0
Reputation: 71461
You can use a dictionary comprehension:
vowels = ['a', 'e', 'i', 'o', 'u']
wordlist = ['big', 'cats', 'like', 'really']
new_words = ''.join(wordlist)
new_counts = {i:sum(i == a for a in new_words) for i in vowels}
Output:
{'a': 2, 'e': 2, 'i': 2, 'o': 0, 'u': 0}
Upvotes: 1
Reputation: 164773
The problem is with this line:
vowelCounts = [aCount, eCount, iCount, oCount, uCount] = (0,0,0,0,0)
vowelCounts
does not get updated if you start incrementing aCount
later.
Setting a = [b, c] = (0, 0)
is equivalent to a = (0, 0)
and [b, c] = (0, 0)
. The latter is equivalent to setting b = 0
and c = 0
.
Reorder your logic as below and it will work:
aCount, eCount, iCount, oCount, uCount = (0,0,0,0,0)
for word in wordlist:
for letter in word:
# logic
vowelCounts = [aCount, eCount, iCount, oCount, uCount]
for vowel, count in zip(vowels, vowelCounts):
print('"{0}" occurs {1} times.'.format(vowel, count))
Upvotes: 6