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
Processing...

Test String

Code Generator

Language

Generated Code

import re regex = re.compile(r"(P [0-9]+ 24 | P [0-9] + -24 |P [0-9][0-9]+ 24 | P [0-9][0-9] + -24 |P [0-9][0-9][0-9] + 24 | P [0-9][0-9][0-9] + -24 |P [0-9][0-9][0-9][0-9]+ 24 | P [0-9][0-9][0-9][0-9] + -24 )", flags=re.MULTILINE) test_str = ("P 89 24 -1.5388040474568784e+01 7.4421775186012660e+00 -1.3143195543234219e+03 1.3168884860257754e+03 8.0419002445999993e+01 44 0 0 -97 0\n" "P 122 -4 -1.4869334602986523e+01 5.7316939411954255e+00 -1.3144161801429666e+03 1.3169704096915282e+03 8.0419002445999993e+01 44 0 0 -370 0\n" "P 493 -24 -1.4690576431881317e+01 7.3848907323212831e+00 -1.3144620647251766e+03 1.3170224315489374e+03 8.0419002445999993e+01 62 0 0 -499 0\n" "E 3 -1 -1.0000000000000000e+00 -1.0000000000000000e+00 -1.0000000000000000e+00 9999 0 970 1 2 0 7 1.7003962000000002e+05 8.5019810000000018e-01 8.5019810000000018e-01 8.5019810000000018e-01 3.0000000000000000e+01 3.8153441026312507e+01 1.0000000000000000e+11\n" "E 4 -1 -1.0000000000000000e+00 -1.0000000000000000e+00 -1.0000000000000000e+00 9999 0 818 1 2 0 7 1.7003962000000002e+05 8.5019810000000018e-01 8.5019810000000018e-01 8.5019810000000018e-01 3.0000000000000000e+01 3.2509364886711985e+01 1.0000000000000000e+11\n" "P 5 2 0 0 3.7531787088999999e+02 3.8383684055052936e+02 8.0419002445999993e+01 22 0 0 -6 0\n" "P 8 24 7.0195398693654170e+00 3.1543502387874696e+01 5.5989200759599044e+01 1.0318077843755555e+02 8.0419002445999993e+01 44 0 0 -50 0\n" "P 67 28 5.8271676589304882e+00 3.3476871962084061e+01 5.6723118833601163e+01 1.0411236719963519e+02 8.0419002445999993e+01 44 0 0 -168 0\n" "P 219 13 6.0328453988772415e+00 3.3531592253635168e+01 5.6777179460595200e+01 1.0417114266715717e+02 8.0419002445999993e+01 44 0 0 -329 0\n" "P 444 -24 6.4646967953734418e+00 3.4909545978243479e+01 5.7879920796889749e+01 1.0525098522544691e+02 8.0419002445999993e+01 62 0 0 -452 0\n" "E 5 -1 -1.0000000000000000e+00 -1.0000000000000000e+00 -1.0000000000000000e+00 9999 0 598 1 2 0 7 1.7003962000000002e+05 0 0 8.5019810000000018e-01 3.0000000000000000e+01 6.8997318544430456e+01 1.0000000000000000e+11") matches = regex.finditer(test_str) for match_num, match in enumerate(matches, start=1): print(f"Match {match_num} was found at {match.start()}-{match.end()}: {match.group()}") for group_num, group in enumerate(match.groups(), start=1): print(f"Group {group_num} found at {match.start(group_num)}-{match.end(group_num)}: {group}")

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