Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

r"
"
gm

Test String

Code Generator

Language

Generated Code

# coding=utf8 # the above tag defines encoding for this document and is for Python 2.x compatibility import re regex = r"(?:\d{1,3})\s+(?:Platform Alarm\(\d+\))\s+\d+\s+(\d+).+(\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}).+nodeBId:(\d+).+Office Name\(Site\)=([\w_]+)" test_str = ("277 Platform Alarm(20420) 1337 198092557 User-defined dry contact alarm 8 Minor SubNetwork=75,MEID=5721,Equipment=1,Rack=1,SubRack=1,Slot=13 2021-06-21 04:27:39 U RNCId: 75; Dry contact ID: 6; Board serial number: 274808900275; U nodeBId:5721 Office ID(Site)=5721/Office Name(Site)=San_Telmo/Alarm Object Type=SDR/Alarm Object ID=5721/Alarm Object Name=San_Telmo/Board Type=SA 75-5721-1_1_13_1_198092557_6\n\n" "12 Radio Controller(1701) 100001 41591 1615258887314 Processing Alarm 83886256 NodeB is out of service Critical SubNet(75)/ManagedElement(75)/Rack No.(1)/Shelf No.(1)/Board No.(8)/CPU No.(1) 2021-03-29 20:08:33 Alarm Object:NODEB; \\nNodeB ID:5433; \\nAlarm sub code:2; \\nIub Transport bearer type:IP V4 Bearer Type; \\nLink Number:1; \\nLink ID list:1126;\\nLogic Position:System No.:0,Module No.:7,Index:0; RNCSCB04 83886768 NCP link failure Office ID(Site)=5433/Office Name(Site)=Tariba/Alarm Object Type=NODEB/Alarm Object ID=5433/Alarm Object Name=Tariba/Board Type=CDR/APP Type=product:wcdma,wcdma/Object MOC=UIUBLINK/Object DN=SubNetwork=75,MEID=75,URncFunction=75,UIubLink=5433\n") matches = re.finditer(regex, test_str, re.MULTILINE) for matchNum, match in enumerate(matches, start=1): print ("Match {matchNum} was found at {start}-{end}: {match}".format(matchNum = matchNum, start = match.start(), end = match.end(), match = match.group())) for groupNum in range(0, len(match.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = match.start(groupNum), end = match.end(groupNum), group = match.group(groupNum))) # Note: for Python 2.7 compatibility, use ur"" to prefix the regex and u"" to prefix the test string and substitution.

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Python, please visit: https://docs.python.org/3/library/re.html