Python regex statement

Question

I'd like to create a regex statement in Python 2.7.8 that will substitute characters. It will work like this...

ó -> o
ú -> u
é -> e
á -> a
í -> i
ù,ú  -> u

These are the only unicode characters that I would like to change. Such unicode characters as, ë, ä I don't want to change. So the word, thójlà will become tholja. I'm sure there is a way so that I don't have to create all the regex separately like below.

word = re.sub(ur'ó', ur'o', word)
word = re.sub(ur'ú', ur'u', word)
word = re.sub(ur'é', ur'e', word)
....

I've been trying to figure this out but haven't had any luck. Any help is appreciated!

Answer 1

Try with str.translate and maketrans...

print('thójlà'.translate(str.maketrans('óúéáíùú', 'oueaiuu')))
# thojlà

This way you ensure the only substitutions you want to make.

If you had many strings to change, you should assign your maketrans to a variable, like

table = str.maketrans('óúéáíùú', 'oueaiuu')

and then, each string can be translated as

s.translate(table)

Answer 2

With String's replace() function you can do something like:

x = "thójlà"                  
>>> x
'thójlà'
>>> x = x.replace('ó','o')
'thojlà'
>>> x = x.replace('à','a')
'thojla'

A generalized way:

# -*- coding: utf-8 -*-

replace_dict = {
    'á':'a',
    'à':'a',
    'é':'e',
    'í':'i',
    'ó':'o',
    'ù':'u',
    'ú':'u'
}

str1 = "thójlà"

for key in replace_dict:
    str1 = str1.replace(key, replace_dict[key])

print(str1) #prints 'thojla'

A third way, if your list of character mappings is getting too large:

# -*- coding: utf-8 -*-

replace_dict = {
    'a':['á','à'],
    'e':['é'],
    'i':['í'],
    'o':['ó'],
    'u':['ù','ú']
}

str1 = "thójlà"

for key, values in replace_dict.items():
    for character in values:
        str1 = str1.replace(character, key)

print(str1)