Regular Expressions 101

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"
^([.\d]+[.\d]+|[.\d])
"
^ asserts position at start of the string
1st Capturing Group
([.\d]+[.\d]+|[.\d])
1st Alternative
[.\d]+[.\d]+
Match a single character present in the list below
[.\d]
+ matches the previous token between one and unlimited 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])
Match a single character present in the list below
[.\d]
+ matches the previous token between one and unlimited 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])
2nd Alternative
[.\d]
Match a single character present in the list below
[.\d]
. matches the character . with index 4610 (2E16 or 568) literally (case sensitive)
\d matches a digit (equivalent to [0-9])
Your regular expression does not match the subject string.

Regular Expression
No Match

r"
"

Test String