Regular Expressions 101

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  • 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"(at the[\n| ]|from the\n|at[\n| ]|faculty of the[\n| ]|faculty of\n)(\w.+[\n]?\w+[ ]?\w+[ ]?\w+[ ]?\w+[ ]?\w+[^(Jan(uary)?|Sep(tember)?(\s\d{4})?|(,)?|author?|(fulfillment)?|laminates]\w+)" test_str = ("MIT Sample:\n" "SOME ASPECTS OF RADIATION INDUCED NUCLEATION IN WATER\n" "by\n" "Chih-Ping Tso\n" "B.Tech., Loughborough University of Technology, United Kingdom\n" "(1968)\n" "Submitted in Partial Fulfillment of\n" "the Requirements for the Degree of\n" "Master of Science\n" "at the\n" "Massachusetts Institute of Technology\n" "August 1970\n" "Signature of Author\n" "Department of Nuclear Engineering\n" "Certified by\n" "Thesis Supervisor\n" "Accepted by\n" "Chairman, Departmental Committee\n" "Archives on Graduate Students\n" "MASS. INST. TECH.\n" "--------------------------------------------------------------------------------\n" "MIT Sample:\n" "PROCEDURES AS A PEPPESFNTATICN FOR DATA\n" "IN A COMPUTER PROGRAM FOR UNDERSTANDING\n" "NATURAL LANGUAGE\n" "by\n" "Terry Winograd\n" "P.A., The Colorado College\n" "(1966)\n" "SUBMITTED IN PARTIAL FULFILLMENT\n" "OF THE REQUIREMENTS FOR THE\n" "DEGREE OF DOCTOR OF\n" "PHILOSOPHY\n" "at the\n" "MASSACHUSETTS INSTITUTE OF\n" "TECHNOLOGY\n" "August, 1970\n" "Signature of Author\n" "Department of Mathematics August 24, 1970\n" "Certified by\n" "Thesis Supervisor\n" "Accepted by\n" "Chairman, Departmental Committee\n" "on Graduate Students\n" "MASS. INST.TECH \n" "SEP 29 1970\n" "LIBRARIES\n" "------------------------------------------------------------------------------\n" "MIT Sample:\n" "AIR RIGHTS DEVELOPMENT OF URBAN TRANSIT CORRIDORS\n" "by\n" "Steven C. Hayes\n" "B.S. BOSTON UNIVERSITY\n" "1971\n" "Submitted in partial fulfillment of\n" "the requirements for the\n" "Degree of Master of Architecture\n" "at the\n" "MASSACHUSETTS INSTITUTE OF TECHNOLOGY\n" "January, 1975\n" "Author\n" "Department of Architecture, Janurary 22, 1975\n" "Certified by\n" "Thesis Supervisor\n" "Accepted by\n" "Chairman, Departmental Committee on Graduate Students\n" "Archives\n" "MASS.INST. TECH.\n" "FEB 13 1975\n" "LIBRARIES\n" "--------------------------------------------------------\n" "MIT Sample:\n" "BUILDINGS AS SYS TEMS\n" "by\n" "Ary M. Pedju\n" "Ir. Ars., Institut Teknologi Bandung,\n" "Bandung, Indonesia, 1963\n" "Submitted in partial fulfillment of the\n" "requirements for the degree of Master in\n" "Architecture at the Massachusetts Institute\n" "of Technology, June 1965.\n" "Submitted by\n" "Ary M. Pedju\n" "Certified by\n" "Eduardo F. Catalano\n" "Thesis Advisor\n" "Accepted by\n" "Lawrence B. Anderson\n" "Head, Department of Architecture\n" "----------------------------------------------------------------------\n" "MIT Sample:\n" "PROCEDURES AS A PEPPESFNTATICN FOR DATA\n" "IN A COMPUTER PROGRAM FOR UNDERSTANDING\n" "NATURAL LANGUAGE\n" "by\n" "Terry Winograd\n" "P.A., The Colorado College\n" "(1966)\n" "SUBMITTED IN PARTIAL FULFILLMENT\n" "OF THE REQUIREMENTS FOR THE\n" "DEGREE OF DOCTOR OF\n" "PHILOSOPHY\n" "at the\n" "MASSACHUSETTS INSTITUTE OF\n" "TECHNOLOGY\n" "August, 1970\n" "Signature of Author\n" "Department of Mathematics August 24, 1970\n" "Certified by\n" "Thesis Supervisor\n" "Accepted by\n" "Chairman, Departmental Committee\n" "on Graduate Students\n" "MASS. INST.TECH \n" "SEP 29 1970\n" "LIBRARIES\n" "---------------------------------------------------------------------------\n" "MIT Sample:\n" "STALL PROPAGATION IN AXIAL COMPRESSORS\n" "ALAN H. STENNING\n" "B.Sc., University of Glasgow\n" "(1950)\n" "S.M., Massachusetts Institute of Technology\n" "(1951)\n" "SUBMITTED IN PARTIAL FULFILLMENT\n" "OF THE REQUIREMENTS FOR THE\n" "DEGREE OF DOCTOR OF SCIENCE\n" "at the\n" "MASSACHUSETTS INSTITUTE OF TECHNOLOGY\n" "June, 1955\n" "Signature of Author\n" "Department of Mechanical Engineering, May 10, 1955\n" "Certified by\n" "Thesis Supervisor\n" "Accepted by\n" "Chairman, Departmental Committee on Graduate Students\n" "------------------------------------------------------------------------------\n" "A HEADQUARTERS FOR THE WORLD HEALTH ORGANIZATION\n" "IN GENEVA, SWITZERLAND\n" "by\n" "Johannes Philipp Holschneider\n" "Diplom Ingenieur, 1959\n" "Technische Hochschule\n" "Karlsruhe/Rhein, Germany\n" "SUBMITTED IN PARTIAL FULFILLMENT OF\n" "THE REQUIREMENTS FOR THE DEGREE\n" "OF MASTER IN ARCHITECTURE at the\n" "MASSACHUSETTS INSTITUTE OF TECHNOLOGY\n" "Signature of Author\n" "Certified by\n" "A Thesis Supervisor\n" "Accepted by\n" "Chairman, Departmental Committee\n" "on Graduate Students\n" "----------------------------------------------------\n" "MIT Sample:\n" "AN INVESTIGATION OF THE POWER SPECTRAL DENSITY OF ATMOSPHERIC TURBULENCE\n" "by\n" "GERHARDT C. CLEMENTSON\n" "B.S. U.S. Military Academy, 1942\n" "M.S. California Institute of Technology, 1945\n" "S.M. Massachusetts Institute of Technology, 1948\n" "SUBMITTED IN PARTIAL FULFILLMENT OF THE\n" "REQUIREMENTS FOR THE DEGREE OF\n" "DOCTOR OF SCIENCE\n" "at\n" "MASSACHUSETTS INSTITUTE OF TECHNOLOGY\n" "1950\n" "Signature of Author\n" "Thesis Supervisor\n" "Chairman, Departmental Committee on Graduate Students\n" "------------------------------------------------------------------\n" "MIT Sample:\n" "OXIDATION STUDIES\n" "IN\n" "METAL-CARBON SYSTEMS\n" "by\n" "Watt Wetmore Webb\n" "S.B. Massachusetts Institute of Technology 1947\n" "Submitted in Partial Fulfillment of the\n" "Requirements for the Degree of\n" "Doctor of Science\n" "from the\n" "Massachusetts Institute of Technology\n" "1955\n" "Signature of Author\n" "Department of Metallurgy\n" "May 16, 1955\n" "Professors in Charge of Research\n" "Chairman, Departmental Committee\n" "on Graduate Students\n" "-------------------------------------------------------------------\n" "MIT Sample:\n" "NEW YWCA BUILDING,\n" "PITTSBURGH, PA.\n" "A thesis is submitted in partial fulfillment of the requirements\n" "for the degree of Master in Architecture at Massachusetts \n" "Institute of Technology\n" "Submitted by\n" "Visvaldis Paukulis\n" "B.Arch., State Inst. of\n" "Technology, Riga, Latvia\n" "To\n" "Lawrence B. Anderson\n" "Head, Department of Architecture, M.I.T.\n" "-------------------------------------------------------------------\n" "MIT Sample:\n" "THE CORROSION OF STEEL IN SALINE\n" "SOLUTIONS OF HYDROGEN SULFIDE\n" "by\n" "SANFORD J. NEUHAUS\n" "Submitted in Partial Fulfillment of the\n" "Requirements for the S.B. Degree\n" "from the\n" "MASSACHUSETTS INSTITUTE OF TECHNOLOGY\n" "1945\n" "Signature of Author\n" "Department of Chemical Engineering, June, 1945\n" "Signature or Thesis Supervisor\n" "-----------------------------------------------------------------\n" "MIT Sample:\n" "THE CHROMIUM-OXYGEN-HYDROGEN EQUILIBRIUM IN LIQUID IRON\n" "by\n" "HSIN-MIN CHEN\n" "B. S., National Tsinghua University\n" "1935\n" "Submitted in Partial Fulfillment of the\n" "Requirements for the Degree of\n" "DOCTOR OF SCIENCE\n" "from the\n" "Massachusetts Institute of Technology\n" "1945\n" "Signature of Author\n" "Department of Metallurgy\n" "June 4, 1945 \n" "Signature of Professor\n" "in Charge of Research \n" "Signature of Chairman\n" "Department Committee\n" "on Graduate Students\n" "--------------------------------------------------------------\n" "MIT Sample:\n" "A CRITICAL SURVEY OF PUBLISHED\n" "PHYSICAL PLANNING PRINCIPLES\n" "by\n" "Thomas A. Reiner\n" "B.A., Swarthmore College\n" "(1952)\n" "Submitted in partial fulfillment of the requirements\n" "for the degree of Master in City Planning\n" "at the\n" "Massachusetts Institute of Technology\n" "(May 1955)\n" "Head, Department of City and Regional Planning\n" "Thesis Advisor\n" "Author\n" "----------------------------------------------------------------------\n" "Virginia Tech Sample:\n" "THEY EXPERIENCE OF THE CATHOLIC DIOCESE OF RICHMOND\n" "WITH ESEA TITLE I, APRIL 1965 -- DECEMBER 1976\n" "by\n" "Richard J.Fenchak \n" "Dissertation submitted to the faculty of\n" "Virginia Polytechnic Institute and State University\n" "in partial fulfillment of the requirements for the degree of\n" "DOCTOR OF EDUCATION\n" "in\n" "Educational Administration\n" "APPROVED:\n" "David J. Parks (Co-Chair) Thomas C. Hunt (Co-Chair)\n" "M. David Alexander James W. Michaels\n" "Kenneth E. Underwood\n" "January, 1986\n" "Blacksburg, Virginia\n" "----------------------------------------------------\n" "Virginia Tech Sample:\n" "ASSESSMENT OF A MENTOR PROGRAM\n" "ON SELF-CONCEPT AND ACHIEVEMENT VARIABLES\n" "OF MIDDLE SCHOOL UNDERACHIEVERS\n" "by\n" "Helene Aiello\n" "Dissertation submitted to the faculty of the Virginia\n" "Polytechnic Institute and State University in partial\n" "fulfillment of the requirements for the degree of\n" "Doctor of Education\n" "in\n" "Administration and Supervision\n" "Of\n" "Special Education\n" "APPROVED:\n" "Philip R. Jones, Chairman Kenneth Underwood\n" "Sylvia Auton\n" "Shirley Jones Ronald McKeen\n" "February 22, 1988\n" "Blacksburg, Virginia\n" "---------------------------------------------------\n" "Virginia Tech Sample:\n" "Synthesis, Characterization and Kinetic Investigations of Heterophase Materials\n" "Prepared Using Group Transfer Polymerization\n" "by\n" "Ann Marie Hellstern\n" "Dissertation submitted to the faculty of the Virginia Polytechnic Institute and\n" "State University in partial fulfillment of the requirements for the degree of\n" "Doctor of Philosophy\n" "in\n" "Chemistry\n" "Approved By:\n" "J.E. McGrath\n" "G. L. Wilkes J. F. Wolfe\n" "B.E. Hanson H.M. Bell\n" "-----------------------------------------------------------\n" "Virginia Tech Sample:\n" "THE KINETICS AND THERMODYNAMICS\n" "OF CLAY MINERAL REACTIONS\n" "by\n" "John Alan Chermak\n" "Dissertation submitted to the faculty of\n" "Virginia Polytechnic Institute and State University\n" "in partial fulfillment of the requirements of the degree of\n" "DOCTOR OF PHILOSOPHY\n" "In\n" "Geology\n" "APPROVED:\n" "J. D. Rimstidt, Chairman\n" "L. W. Zelazny J. R. Craig\n" "R. J. Bodnar S. C. Eriksson\n" "November, 1989\n" "Blacksburg, Virginia\n" "-------------------------------------------------------------\n" "Virginia Tech Sample:\n" "STRATEGIES AND TACTICS TO ACCESS INTUITION:\n" "A LOOK AT THE MOMENT OF SOLUTION\n" "by\n" "Linda E. Morris\n" "Dissertation submitted to the faculty of the\n" "Virginia Polytechnic Institute and State University\n" "in partial fulfillment of the requirements for the degree of\n" "DOCTOR OF EDUCATION\n" "Adult Continuing Education\n" "Approved:\n" "Dr. Marcie Boucouvalas, Chairperson\n" "Dr. Neal E. Chalofsky Dr. Hugo A. Keesing\n" "Dr. Ronald L. McKeen Dr. Orion F. White\n" "March 1, 1990\n" "Blacksburg, Virginia\n" "----------------------------------------------------------\n" "Virginia Tech Sample:\n" "PREDICTION MODEL FOR THE ONSET OF EDGE-EFFECT DELAMINATION\n" "at holes in composite laminates\n" "by\n" "Doron Shalev\n" "Dissertation submitted to the faculty of the\n" "Virginia Polytechnic Institute and State University\n" "in partial fulfillment of the requirements for the degree of\n" "DOCTOR OF PHILOSOPHY\n" "in\n" "Engineering Science and Mechanics\n" "APPROVED:\n" "K. L. Reifsnider\n" "C. W. Smith R. T. Haftka\n" "R. M. Jones R. A. Heller\n" "July, 1988\n" "Blacksburg, Virginia") 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