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

use strict; my $str = '1.249132165057832031e+13 1.638194600635518555e+13 2.127995187558799219e+13 2.744617593148214062e+13 -2.558800658636701519e+28 5.918883595148564680e+30 3.603563681248702509e+31 4.325917213186498068e+31 4.911908042151239481e+31 4.463331378152286632e+31 3.684371076399113503e+31 2.500614504012405068e+31 9.997365425073173512e+30 -7.046725649106466938e+30 -2.192076417151744811e+31 -2.531287564917444482e+31 -6.962936418905874724e+30 3.281685507310205847e+31 9.241630178064907840e+31 1.730544785932614751e+32 2.619210949875333106e+32 2.984440142196566918e+32 8.964375812060072923e+31 -8.515727465135046667e+32 -3.425309034394939997e+33 -8.145884847188906515e+33 -9.922370830834364410e+33 -2.119464668318252366e+28 -1.689726703118075140e+27 1.440101653069986610e+26 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 6.186324149659251562e+13 8.113154959294240625e+13 1.053889122977165625e+14 1.359271226298647969e+14 -2.097046363337115528e+28 4.850777756495711585e+30 2.953274256558218597e+31 3.545273642763729060e+31 4.025456872055449111e+31 3.657581460085835446e+31 3.018816679659856350e+31 2.048223110003727437e+31 8.176806147340775115e+30 -5.796250740354887641e+30 -1.798839398031696094e+31 -2.076444435341100150e+31 -5.711669151245612857e+30 2.691583747083509247e+31 7.579958708961477309e+31 1.419395486743453834e+32 2.148287875274468622e+32 2.447859658750551118e+32 7.352862842410293685e+31 -6.984595303325589259e+32 -2.809449882735912952e+33 -6.681296633318354125e+33 -8.138406580426555140e+33 -1.740744048703962454e+28 -1.411749034480591280e+27 8.079362883576220633e+25 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00 0.000000000000000000e+00'; my $regex = qr/([-+]?\d\.(?!0+e\+0+)\S+)\s+(?:0\.0+e\+00\s*)+/p; if ( $str =~ /$regex/g ) { print "Whole match is ${^MATCH} and its start/end positions can be obtained via \$-[0] and \$+[0]\n"; # print "Capture Group 1 is $1 and its start/end positions can be obtained via \$-[1] and \$+[1]\n"; # print "Capture Group 2 is $2 ... and so on\n"; } # ${^POSTMATCH} and ${^PREMATCH} are also available with the use of '/p' # Named capture groups can be called via $+{name}

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 Perl, please visit: http://perldoc.perl.org/perlre.html