Regex to Match Dollar Amounts with Optional Cents

Problem: How to match dollar amounts in a given string? If cent amounts are given, those should match as well.

Solution: You can use regular expression pattern '(\$[0-9]+(.[0-9]+)?)' to find all numbers that start with a dollar symbol, followed by an arbitrary number of numerical digits, followed by an optional decimal point and an arbitrary number of numerical digits.

Here’s the code:

import re

report = '''
If you invested $1 in the year 1801, you would have $18087791.41 today.
This is a 7.967% return on investment.
But if you invested only $0.25 in 1801, you would end up with $4521947.8525.
'''

dollars = [x[0] for x in re.findall('(\$[0-9]+(\.[0-9]+)?)', report)]

print(dollars)

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