Regular Expressions 101

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/
^([-+]?[1-8]?\d(?:\.\d+)?|90(?:\.0+)?),\s*([-+]?(?:180(?:\.0+)?|(?:(?:1[0-7]\d)|(?:[1-9]?\d))(?:\.\d+)?))$
/
^ asserts position at start of the string
1st Capturing Group
([-+]?[1-8]?\d(?:\.\d+)?|90(?:\.0+)?)
1st Alternative
[-+]?[1-8]?\d(?:\.\d+)?
Match a single character present in the list below
[-+]
? 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)
This hyphen is treated literally, which might be confusing for others. Consider escaping it or placing at the start or end of the class!
+ matches the character + with index 4310 (2B16 or 538) literally (case sensitive)
Match a single character present in the list below
[1-8]
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
1-8 matches a single character in the range between 1 (index 49) and 8 (index 56) (case sensitive)
\d matches a digit (equivalent to [0-9])
Non-capturing group
(?:\.\d+)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
2nd Alternative
90(?:\.0+)?
90
matches the characters 90 literally (case sensitive)
Non-capturing group
(?:\.0+)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
0
matches the character 0 with index 4810 (3016 or 608) literally (case sensitive)
, matches the character , with index 4410 (2C16 or 548) literally (case sensitive)
\s
matches any whitespace character (equivalent to [\r\n\t\f\v ])
* matches the previous token between zero and unlimited times, as many times as possible, giving back as needed (greedy)
2nd Capturing Group
([-+]?(?:180(?:\.0+)?|(?:(?:1[0-7]\d)|(?:[1-9]?\d))(?:\.\d+)?))
Match a single character present in the list below
[-+]
? 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)
This hyphen is treated literally, which might be confusing for others. Consider escaping it or placing at the start or end of the class!
+ matches the character + with index 4310 (2B16 or 538) literally (case sensitive)
Non-capturing group
(?:180(?:\.0+)?|(?:(?:1[0-7]\d)|(?:[1-9]?\d))(?:\.\d+)?)
1st Alternative
180(?:\.0+)?
180
matches the characters 180 literally (case sensitive)
Non-capturing group
(?:\.0+)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
0
matches the character 0 with index 4810 (3016 or 608) literally (case sensitive)
2nd Alternative
(?:(?:1[0-7]\d)|(?:[1-9]?\d))(?:\.\d+)?
Non-capturing group
(?:(?:1[0-7]\d)|(?:[1-9]?\d))
1st Alternative
(?:1[0-7]\d)
Non-capturing group
(?:1[0-7]\d)
1 matches the character 1 with index 4910 (3116 or 618) literally (case sensitive)
Match a single character present in the list below
[0-7]
0-7 matches a single character in the range between 0 (index 48) and 7 (index 55) (case sensitive)
\d matches a digit (equivalent to [0-9])
2nd Alternative
(?:[1-9]?\d)
Non-capturing group
(?:[1-9]?\d)
Match a single character present in the list below
[1-9]
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
1-9 matches a single character in the range between 1 (index 49) and 9 (index 57) (case sensitive)
\d matches a digit (equivalent to [0-9])
Non-capturing group
(?:\.\d+)?
? matches the previous token between zero and one times, as many times as possible, giving back as needed (greedy)
\. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\d
matches a digit (equivalent to [0-9])
+ matches the previous token between one and unlimited times, as many times as possible, giving back as needed (greedy)
$ asserts position at the end of the string, or before the line terminator right at the end of the string (if any)
Your regular expression does not match the subject string.Try launching the debugger to find out why.

Regular Expression
No Match

/
/

Test String