python multiple characters replace in string not working with pipe

Question

I am trying to match and replace multiple characters in a string.

str1 = 'US$0.18'
reg = 'AUS$|US$|HK$|MK$'
#reg = 'AUS\$|US\$|HK\$|MK\$' <-- doesn't work
#reg = 'US$' <-- this works
str1 = str1.replace(reg, '')

This doesn't replace US$ which I expected to.

What am I missing here?

You're not using regular expressions at all, this is just plain string replacement. — mkrieger1, Aug 09 '21 at 12:00
You are looking for [re.sub](https://docs.python.org/3/library/re.html#re.sub) — Maurice Meyer, Aug 09 '21 at 12:01
(also note that `$` has special meaning in regular expressions and presumably you need to escape it) — mkrieger1, Aug 09 '21 at 12:02
@mkrieger1 yes.. I even tried to escape the character but same result — Azima, Aug 09 '21 at 12:05
Yes of course, see earlier comments. This is another, better, duplicate: https://stackoverflow.com/questions/16720541/python-string-replace-regular-expression — mkrieger1, Aug 09 '21 at 12:06
Are you trying to replace text that matches ```AUS$|US$|HK$|MK$``` with ```''``` ? — Ram, Aug 09 '21 at 12:35

Ram · Accepted Answer · 2021-08-09T12:46:29.553

You can do that using re.sub(). Since $ has a special meaning in re, we need to escape it by appending a \ in front of it.

(AUS|US|HK|MK)\$ - Finds a match that has either of AUS, US, HK or MK that is followed by a $.
re.sub(r'(AUS|US|HK|MK)\$',r'', s) - Replaces the matched string with a '' of string s.

import re

s = "US$0.18 AUS$45 HK$96"
x = re.sub(r'(AUS|US|HK|MK)\$',r'', s)
print(x)

0.18 45 96

1 Answers1