Question

I have a code in Python and want to find vowels in a string.
The code I have written is following….I tried different combinations for using For-Loop, but it throws two different errors;

1. ‘int’ object is not iterable,
2. string indices must be integers, not str.

how can I find all vowels in a line?

str1 = 'sator arepo tenet opera rotas'
vow1 = [str1[i] for i in str1 if  str1[i] is 'a' | 'e' | 'o']

Answer 1

what about:

vowels = [ c for c in str1 if c in 'aeo' ]

You’re getting errors because when you loop over a string, you loop over the characters in the string (not string indices) and because 'a' | 'e' | 'o' doesn’t make sense for strings — (they don’t support the | operator)

>>> str1 = 'sator arepo tenet opera rotas'
>>> vowels = [ c for c in str1 if c in 'aeo' ]
>>> print vowels
['a', 'o', 'a', 'e', 'o', 'e', 'e', 'o', 'e', 'a', 'o', 'a']

---

One final comment, you shouldn’t use is to test for equality. is tests for identity. A simple test:

a = 565
b = 565
print a == b #True
print a is b #False (!)

The reason is because a and b reference different objects that have the same value.