Regular Expressions 101

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/
(-)?([0-9]{1,3})(,)?([0-9]{1,3})?(,)?([0-9]{1,3})?(\.)([0-9]{2})
/
gm
1st Capturing Group
(-)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
- matches the character - with index 4510 (2D16 or 558) literally (case sensitive)
2nd Capturing Group
([0-9]{1,3})
Match a single character present in the list below
[0-9]
{1,3} matches the previous token between 1 and 3 times, as many times as possible, giving back as needed (greedy)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
3rd Capturing Group
(,)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
, matches the character , with index 4410 (2C16 or 548) literally (case sensitive)
4th Capturing Group
([0-9]{1,3})?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
Match a single character present in the list below
[0-9]
{1,3} matches the previous token between 1 and 3 times, as many times as possible, giving back as needed (greedy)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
5th Capturing Group
(,)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
, matches the character , with index 4410 (2C16 or 548) literally (case sensitive)
6th Capturing Group
([0-9]{1,3})?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
Match a single character present in the list below
[0-9]
{1,3} matches the previous token between 1 and 3 times, as many times as possible, giving back as needed (greedy)
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
7th Capturing Group
(\.)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
8th Capturing Group
([0-9]{2})
Match a single character present in the list below
[0-9]
{2} matches the previous token exactly 2 times
0-9 matches a single character in the range between 0 (index 48) and 9 (index 57) (case sensitive)
Global pattern flags
g modifier: global. All matches (don't return after first match)
m modifier: multi line. Causes ^ and $ to match the begin/end of each line (not only begin/end of string)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/
gm

Test String

Regex Debugger

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