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

/
/
im

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"(http:\/\/dx.doi.org\/10|10| DOI: 10|DOI:10).\d{4,9}\/[-._;()\/:0-9]+" test_str = ("Small Group Research2014, Vol. 45(6) 671 Œ703© The Author(s) 2014Reprints and permissions:sagepub.com/journalsPermissions.nav DOI: 10.1177/1046496414552285sgr.sagepub.comArticleA Conceptual Review of Emergent State \n" "Measurement: Current \n" "Problems, Future \n" "SolutionsChris W. Coultas1, Tripp Driskell2, C. Shawn Burke1, and Eduardo Salas1AbstractTeam research increasingly incorporates emergent states as an integral \n" "mediator between team inputs and outcomes. In conjunction with this, we \n\n" "have witnessed a proliferation and fragmentation of measurement techniques \n\n" "associated with emergent states. This inconsistency in measurement presents \n" "a problem for scientists and practitioners alike. For the scientist, it becomes \n" "difficult to better understand the nature and effects of various emergent \n\n" "states on team processes and outcomes. For the practitioner, it complicates \n" "the process of measurement development, selection, and implementation. \n" "To address these issues, we review the literature on emergent states focusing \n" "on various measurement strategies, to better unpack best practices. In so \n" "doing, we highlight existing research that suggests innovative solutions to the \n" "conceptual, methodological, and logistical problems that consistently plague \n" "emergent state research. Our aim is to enhance emergent state theory by \n" "applying psychometric principles to the measurement techniques associated \n" "with them.1University of Central Florida, Orlando, USA2The Florida Maxima Corporation, Orlando, USACorresponding Author:Chris W. Coultas, University of Central Florida, 4000 Central Florida Blvd., Psychology Bldg. \n" "99, Ste. 320, Orlando, FL 32816, USA. \n" "Email: ccoultas@ist.ucf.eduThis article is part of the special issue: 2014 Annual Review Issue, Small Group Research, Volume 45(6).552285SGRXXX10.1177/1046496414552285\n" "Small Group ResearchCoultas et al.research-article\n" "2014\n") matches = re.search(regex, test_str, re.IGNORECASE | re.MULTILINE) if matches: print ("Match was found at {start}-{end}: {match}".format(start = matches.start(), end = matches.end(), match = matches.group())) for groupNum in range(0, len(matches.groups())): groupNum = groupNum + 1 print ("Group {groupNum} found at {start}-{end}: {group}".format(groupNum = groupNum, start = matches.start(groupNum), end = matches.end(groupNum), group = matches.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