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

Substitution

Processing...

Code Generator

Language

Generated Code

re = /^.*:\s+([A-Z].*)_(\D+)_(\d+).*/m str = 'dog-Cf-Nox1: Porites_lobata_1381 49.126 572 275 8 1 564 1 564 0.0 563 dog-Cf-Nox1: Porites_australiensis_5912 48.776 572 277 8 1 564 1 564 0.0 560 dog-Cf-Nox1: Astreopora_sp_20372 48.776 572 276 9 1 564 1 563 0.0 555 dog-Cf-Nox1: Montastraea_cavernosa_106939 48.148 567 279 7 5 564 6 564 0.0 555 dog-Cf-Nox1: Seriatopora_hystrix_66126 50.000 554 262 7 18 564 19 564 0.0 553 dog-Cf-Nox1: Porites_australiensis_4812 46.946 573 287 6 1 564 1 565 0.0 553 dog-Cf-Nox1: Stylophora_pistillata_7748 49.009 555 268 7 17 564 18 564 0.0 550 dog-Cf-Nox1: Porites_lobata_724 46.435 575 289 7 1 564 1 567 0.0 548 dog-Cf-Nox1: Acropora_digitifera_16260 46.935 571 288 7 1 564 1 563 0.0 538' subst = '\\1,\\2,\\3' result = str.gsub(re, subst) # Print the result of the substitution puts result

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 Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html