How do I make all words in a list of words lowercase in python?

Question

I'm trying to make all entries in my list dictionary lowercase but I cant figure out a way to do this

def get_entire_word_list():
dictionary = []
f = open("dictionary.txt", "r")
for x in f:
    dictionary.append(x.strip('\n'))

f.close()

for x in dictionary:
    x.lower()

for x in dictionary:
    print(x)

return dictionary

This just won't do it :(

I tried

for x in dictionary:
    x = x.lower()

but that wont do it either.

Thanks for any tips

Just call `lower` as you add the strings. `dictionary.append(x.strip('\n').lower())`. — chepner, Jan 20 '22 at 19:51
`x = x.lower()` just re-assigns a local variable `x`, where the *new string* from `x.lower()` is assigned to. This does nothing to modify the list. To do this, you'd have to modify the list, or just create a new one. see the linked duplicate — juanpa.arrivillaga, Jan 20 '22 at 19:51
@chepner AHH THANKS A LOT!! I tried that before but I put the .lower after the whole expression, like this: `dictionary.append(x.strip('\n')).lower()` That just threw an error — qwertzniki6, Jan 20 '22 at 19:56

Simon Hawe · Answer 1 · 2022-01-20T19:50:59.880

2

If you have a list of strings, called dictionary, you can use a list comprehension like

dictionary = [x.lower() for x in dictionary]

to create a new list that contains only lowered cased string.

edited Jan 20 '22 at 19:50

answered Jan 20 '22 at 19:48

Simon Hawe

3,968
6
14

Without context, this isn't a useful answer. Just putting that line in there will do nothing except create a new list, and nothing in `dictionary` will be modified – juanpa.arrivillaga Jan 20 '22 at 19:49
I implemented `[x.lower() for x in dictionary]` but it doesnt work either – qwertzniki6 Jan 20 '22 at 19:52
@qwertzniki6 you'd have to assign the result back to the variable `dictionary` – juanpa.arrivillaga Jan 20 '22 at 19:54

How do I make all words in a list of words lowercase in python?

1 Answers1