Yeah that’s on purpose. That’s often used in sciences to mark significant digits.
The thing I’m confused by in yours is you’re escaping the parenthesis, so there need to be literal parenthesis in the matching number, or that’s what it showed in the regex checker.
The parens in my regex group part of the regex, so the following ‘?’ makes the entire group optional.
Your regex matches (for example) ‘5.’ as a number.
Mine is also slightly wrong, it matches a blank string as a number. Here’s a better one:
[0-9]+\(\.[0-9]+\)?Yeah that’s on purpose. That’s often used in sciences to mark significant digits.
The thing I’m confused by in yours is you’re escaping the parenthesis, so there need to be literal parenthesis in the matching number, or that’s what it showed in the regex checker.
Whether or not you need to escape parens depends on the regex implementation.