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

/
/
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"lat" test_str = ("# Degrees minutes\n" "# \\d+\\W+\\d+\\W+\\d+\\.?\\d*\n\n" "\"-77.566296, 41.471044\"\n" "5234098, 29384\n\n" "40° 37' 03.620\\\" N\n\n" " 39.9153 N 78.3405 W\n\n\n" "CORNPLANTER BRIDGE QUAD.--LAT. 41-48-18.41--LONG. -78-52-51.26\n" "LUDLOW QUAD--LAT.41-39-16.0500--LONG.-78-55-11.1200\n" "LAT 41-45-00 LONG 75-50-00\n" "LAT 41.73381944 LONG -75.87685278\n" "Ref Latitude 41 81833 - Ref Longitude -75 15167\n" "LAT 41 56' 11.28\\\" N--LON 76 52' 03.36\\\" W\n\n" "[891] \"McNett TOWNSHIP\" \n" "[892] \"TWP - Range - Sec\" \n" "[893] \"MONETT TOWNSHIP,LYCOMING COUNTY,PA\n" "LAT 41 42 12.6700\n" "LAT 41 DEG 43-52-0300 \n" "LAT 41.4122917\n" "Latitude: 40.752 N\n" "Lat. 40.72617600* N\n" "Longitude: 80-24-41 W\n" "Latitude: 40.653407 N\n" "LAT: 40.687574\n" "LAT\n" "LAT: 40-50-13.7000\n" "Latitude: 40.83721N\n" "LATITUDE\n" "Latitude 39-53-12.33 N\n" "LATITUDE 39-53.442319 N\n" "Latitude 39-53-43.26 N\n" "Latitude 39.8949 N\n" "LAT: 41-43-26.9600 N\n" "LAT: 41-43-29.83\n" "LAT: 41*51'42.99\\\" N\n" "LAT: 41-46-9.8700 N\n" "LATITUDE: 41* 42' 40.19\\\"\n\n" "41-42-40.19 LAT\n\n" "API # 37-015-208801-00--X=2201217.34E Y=632183.50N--LAT\"\n" "03-029-01") 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