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

/
/
gmiU

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"[ ^\s]([ ]{1,})[ ^\s]" test_str = "5382948 EGELSTON^ELIZABETH 0102126763 1942-09-17 00:00:00.000 F 2003-02-09 00:00:00.000 1899-12-30 19:39:10.000 CT03011350 28465 1.2.124.113532.10.7.222.5.20030209.190851.3087742 NULL UNKNOWN^RADNET CT NULL PE CHEST 764A NULL BODY Northwestern Memorial Hosp. NMH5_OC0 NULL NULL NULL 4 467 544 NULL 2003-04-27 22:56:55.000 NULL 2003-04-27 23:14:42.000 8 2009-06-07 09:22:07.640 2015-11-14 03:54:07.407 2015-11-14 03:54:08.290 NULL NULL CT NULL 5706865 5382948 CT 1.2.840.113619.2.55.1.1762864829.1989.1044811980.588.5 5 Recon 2: ROUTINE PE NULL 5.7 ROUTINE PE NULL 1.2.124.113532.10.7.222.5.20030209.190851.3087742.9814.0.12 4 200 NULL NULL NULL 8 NULL NULL NULL 7276786 5706865 3 NULL 4 NULL 0102126763\\1_2_124_113532_10_7_222_5_\\7276786.0 NULL 289158 NULL 3 ASP_NMH_99_LIB2 \\\\asp1nsx02\\ASP_NMH_99_LIB2\\Incoming \\\\asp1nsx02\\ASP_NMH_99_LIB2\\Images LOCAL" matches = re.finditer(regex, test_str, re.MULTILINE | re.IGNORECASE) 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