如何编写正则表达式模式以匹配字符串结尾或字符串开头的货币符号

Question

I'm trying to write a regex pattern in Python that will only match the substrings which have a currency symbol/word attached.

'50,000 and £200.6m, 50p, 500m euro, 800bn euros, $15bn and $99.99. The year 2006 is 20% larger.' 

1. £200.6m
2. 50p
3. 500m euro
4. 800bn euros
5. $15bn
6. $99.99

I do not want numbers that are not currency related to match, such as plain numbers, percentages or years.

(^(£|\$)?)\d+([.,]\d*)?|(\d+([.,]\d*)?(p|(bn|m)|(\seuro(s)))$)

1. 50,000

Evidently the regex isn't working at all as I expect. It should either match a substring if it begins with a currency symbol or if it ends with one.

Answer 1

You might use a pattern to match either the euro or dollar sign [£$] , the value optionally followed by p m or bn .

Or match the value followed by p m or bn and euro with optional s

(?:[£$]\d+(?:\.\d+)?(?:[pm]|bn)?|\d+(?:\.\d+)?(?:[pm]|bn)(?: euros?)?)

Explanation

• (?: Non capture group
  • [£$] A character class matching either £ or $
  • \d+(?:\.\d+)? Match 1+ digits with an optional decimal part
  • (?:[pm]|bn)? Optionally match either p or m or bn
  • | Or
  • \d+(?:\.\d+)? Match 1+ digits with optional decimal part
  • (?:[pm]|bn) Match either p or m or bn
  • (?: euros?)? Optionally match a space and euro with optional s
• ) Close group

Regex demo

Answer 2

Something like this would do it:

(?:£|\$)(?:\d*\.)?\d+(?:m|bn)?|(?:\d*\.)?\d+(?:m|bn)? ?(?:p|euros?)

Just keep adding the currencies you wish to catch to the respective (?:£|\$) or (?:p|euros?) sections. Ditto for adding items to (?:m|bn)

https://regex101.com/r/3K9jmR/1