Python Regex To Match Currency With Or Without Comma Or Decimal

How to write regex that can 1. match currency which may or may not include a comma or decimal and 2. match the currency code only. What I see is mostly matching currency symbols. I

Solution 1:

Get the Currency:

Having an exhaustive list of valid currencies might not be feasible but if it is a limited number of currencies then you can do that like this:

re.findall('USD|CAD','USD1 USD1.00 USD100.00 USD1,000 CAD1,000.00 123XXX123')

Output:

['USD', 'USD', 'USD', 'USD', 'CAD']

Get the amount:

Using capturing group, re.findall returns each capture in a tuple. Using a non-capturing group (?:) will solve the issue.

re.findall('(?<=USD|CAD)\d{1,3}(?:,\d{3})*(?:\.\d+)?(?=\s)','Userid 9XXXX219 sales USD300,000.00 On 01-JUL-2016 08:34:32')

Output:

['300,000.00']

Illustration with the example text:

re.findall('(?<=USD|CAD)\d{1,3}(?:,\d{3})*(?:\.\d+)?(?=\s)','USD1 USD1.00 USD100.00 USD1,000 CAD1,000.00 123XXX123')

Output:

['1', '1.00', '100.00', '1,000', '1,000.00']

Read more the following here:

(?=) - positive lookahead (?<=) - positive lookbehind

Solution 2:

To match currency only you can use : (\d[0-9,.]+)

and to match currency codes you can use : ([A-Z]+)

Demo and Explaination

Solution 3:

'\d+([.,]?\d*)*' that should match all cases. If you want, you can also add space. Like this:

'\d+([., ]?\d*)*'

For the currency codes: '[A-Z]{3}' should work.

P.S. As per SilentMonk suggestion for the non-capture groups:

(?:[A-Z]{3})(?:\d+(?:[.,]?\d*)*)