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Python Python Collections (Retired) Lists Redux Disemvoweled

Posted by Jay Harper-Harrison
Jay Harper-Harrison
1,044 Points

Why does it do this?

state_names = ["Alabama", "California", "Oklahoma","Florida"]
vowels = list('aeiou')
output = []

for state in state_names:
  state_list = list(state.lower())

  for vowel in vowels:
    while True:
      try:
        state_list.remove(vowel)
      except:
        break
    output.append(''.join(state_list).capitalize())

print(output)

My code prints this out: ['Lbm', 'Lbm', 'Lbm', 'Lbm', 'Lbm', 'Cliforni', 'Cliforni', 'Clforn', 'Clfrn', 'Clfrn', 'Oklhom', 'Oklhom', 'Oklhom', 'Kl hm', 'Klhm', 'Florid', 'Florid', 'Flord', 'Flrd', 'Flrd'] can someone help me?

2 Answers

Kenneth Love
STAFF
Kenneth Love
Treehouse Guest Teacher
Kenneth Love
Kenneth Love
Treehouse Guest Teacher

Your output.append is at the same indentation as your while, so you're appending for each vowel. Since there are 5 vowels, you get 5 appends. Put the output.append at the same level as the for and you shouldn't have that problem.

Jay Harper-Harrison
Jay Harper-Harrison
1,044 Points

Could you explain why it appends for each vowel please?

Kenneth Love
Kenneth Love
Treehouse Guest Teacher
Kenneth Love
Kenneth Love
Treehouse Guest Teacher

Jay Harper-Harrison Sure. Python uses indentation to see what code belongs inside what block instead of braces like many other languages. Let's rewrite part of yours as some pseudo-code that uses braces to show blocks.

for vowel in vowels {
    while True {
        try {
            state_list.remove(vowel)
        } except {
            break
        }
    }
    output.append(''.join(state_list).capitalize())
}

As you see in the above example, your output.append() belongs to the for loop that's looping over the vowels. So the loop goes through with "a", removing it from the word, if possible, then appending the current state of the word to the output list. Then it goes through the loop with "e", removing it if possible and appending. Then with "i". Then with "o", and so on.

If you unindent, or dedent, your output.append() line by one tab/set of spaces, it'll be outside of the for loop and will only append once all of the vowels have been processed.

Andrew Molloy
Andrew Molloy
37,259 Points
Andrew Molloy
Andrew Molloy
37,259 Points

You're looping through your append too, remove an indent for your output.append line to take it out of the while loop