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Benedictt Vasquez
2,130 PointsHow I know where is anything in a list?
Ex.:
>>> my_list = list('Hello')
>>> 'H' in my_list
True
# I know that "H" is in the list, but if want to know where is 'H' in the list, How I do it?
[MOD: added ```python formatting -cf]
3 Answers
Chris Freeman
Treehouse Moderator 68,441 Points# For a list you can use 'index'. It throws error if item not found
>>> my_list = list('Hello')
>>> 'H' in my_list
True
>>> my_list.index('H')
0
>>> my_list.index('l')
2
>>> my_list.index('z')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ValueError: 'z' is not in list
# Strings can act like lists
>>> my_string = 'Hello'
>>> 'H' in my_string
True
# find returns index, or '-1' if not found
>>> my_string.find('l')
2
>>> my_string.find('z')
-1
# Can also use 'index()'. It throws error if item not found
>>> my_string.index('o')
4
>>> my_string.index('z')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ValueError: substring not found
# can use 'index' on string but throws an error if target not found
More info on str.find(), more info on index() under list type
Benedictt Vasquez
2,130 PointsExcelente!! Thank you
ibrahim Warsame
7,803 PointsGood answer man