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

$re = '/^tf_horovod_(.*?)_(\d*)_(\d*)\/.*total images\/sec: (\d*).(\d*)$/m'; $str = 'tf_horovod_alexnet_1_1//tf_horovod_alexnet_1_1_han0044_9841783:total images/sec: 558.63 tf_horovod_alexnet_1_10//tf_horovod_alexnet_1_10_han0012_9841791:total images/sec: 3738.39 tf_horovod_alexnet_1_12//tf_horovod_alexnet_1_12_han0002_9841792:total images/sec: 4367.44 tf_horovod_alexnet_1_14//tf_horovod_alexnet_1_14_han0012_9841793:total images/sec: 5028.34 tf_horovod_alexnet_1_16//tf_horovod_alexnet_1_16_han0002_9841794:total images/sec: 5534.41 tf_horovod_alexnet_1_2//tf_horovod_alexnet_1_2_han0043_9841784:total images/sec: 879.33 tf_horovod_alexnet_1_3//tf_horovod_alexnet_1_3_han0042_9841785:total images/sec: 1242.05 tf_horovod_alexnet_1_4//tf_horovod_alexnet_1_4_han0020_9841786:total images/sec: 1593.18 tf_horovod_alexnet_1_5//tf_horovod_alexnet_1_5_han0025_9841787:total images/sec: 1954.82 tf_horovod_alexnet_1_6//tf_horovod_alexnet_1_6_han0020_9841788:total images/sec: 2255.87 tf_horovod_alexnet_1_7//tf_horovod_alexnet_1_7_han0032_9841789:total images/sec: 2630.68 tf_horovod_alexnet_1_8//tf_horovod_alexnet_1_8_han0002_9841790:total images/sec: 2936.90 tf_horovod_alexnet_2_1//tf_horovod_alexnet_2_1_han0042_9841795:total images/sec: 727.25 tf_horovod_alexnet_2_10//tf_horovod_alexnet_2_10_han0002_9841803:total images/sec: 7133.82 tf_horovod_alexnet_2_2//tf_horovod_alexnet_2_2_han0043_9841796:total images/sec: 1652.27 tf_horovod_alexnet_2_3//tf_horovod_alexnet_2_3_han0042_9841797:total images/sec: 2244.21 tf_horovod_alexnet_2_4//tf_horovod_alexnet_2_4_han0023_9841798:total images/sec: 3107.98 tf_horovod_alexnet_2_5//tf_horovod_alexnet_2_5_han0020_9841799:total images/sec: 3841.47 tf_horovod_alexnet_2_6//tf_horovod_alexnet_2_6_han0002_9841800:total images/sec: 4565.75 tf_horovod_alexnet_2_8//tf_horovod_alexnet_2_8_han0017_9841802:total images/sec: 5965.89 tf_horovod_googlenet_1_1//tf_horovod_googlenet_1_1_han0041_9841735:total images/sec: 111.51 tf_horovod_googlenet_1_10//tf_horovod_googlenet_1_10_han0012_9841743:total images/sec: 1074.32 tf_horovod_googlenet_1_12//tf_horovod_googlenet_1_12_han0002_9841744:total images/sec: 1304.12 tf_horovod_googlenet_1_14//tf_horovod_googlenet_1_14_han0012_9841745:total images/sec: 1501.07 tf_horovod_googlenet_1_16//tf_horovod_googlenet_1_16_han0002_9841746:total images/sec: 1646.49 tf_horovod_googlenet_1_2//tf_horovod_googlenet_1_2_han0041_9841736:total images/sec: 219.21 tf_horovod_googlenet_1_3//tf_horovod_googlenet_1_3_han0041_9841737:total images/sec: 328.94 tf_horovod_googlenet_1_4//tf_horovod_googlenet_1_4_han0032_9841738:total images/sec: 437.95 tf_horovod_googlenet_1_5//tf_horovod_googlenet_1_5_han0020_9841739:total images/sec: 546.25 tf_horovod_googlenet_1_6//tf_horovod_googlenet_1_6_han0031_9841740:total images/sec: 657.16 tf_horovod_googlenet_1_7//tf_horovod_googlenet_1_7_han0020_9841741:total images/sec: 765.23 tf_horovod_googlenet_1_8//tf_horovod_googlenet_1_8_han0002_9841742:total images/sec: 842.25 tf_horovod_googlenet_2_1//tf_horovod_googlenet_2_1_han0044_9841747:total images/sec: 208.41 tf_horovod_googlenet_2_10//tf_horovod_googlenet_2_10_han0019_9841755:total images/sec: 2166.72 tf_horovod_googlenet_2_14//tf_horovod_googlenet_2_14_han0016_9841757:total images/sec: 2994.40 tf_horovod_googlenet_2_2//tf_horovod_googlenet_2_2_han0043_9841748:total images/sec: 441.89 tf_horovod_googlenet_2_3//tf_horovod_googlenet_2_3_han0042_9841749:total images/sec: 660.91 tf_horovod_googlenet_2_4//tf_horovod_googlenet_2_4_han0035_9841750:total images/sec: 875.64 tf_horovod_googlenet_2_5//tf_horovod_googlenet_2_5_han0020_9841751:total images/sec: 1092.19 tf_horovod_googlenet_2_6//tf_horovod_googlenet_2_6_han0031_9841752:total images/sec: 1293.98 tf_horovod_googlenet_2_7//tf_horovod_googlenet_2_7_han0002_9841753:total images/sec: 1528.10 tf_horovod_inception3_1_1//tf_horovod_inception3_1_1_han0002_9841711:total images/sec: 30.58 tf_horovod_inception3_1_10//tf_horovod_inception3_1_10_han0012_9841719:total images/sec: 275.87 tf_horovod_inception3_1_12//tf_horovod_inception3_1_12_han0002_9841720:total images/sec: 329.99 tf_horovod_inception3_1_14//tf_horovod_inception3_1_14_han0016_9841721:total images/sec: 385.50 tf_horovod_inception3_1_16//tf_horovod_inception3_1_16_han0002_9841722:total images/sec: 439.23 tf_horovod_inception3_1_2//tf_horovod_inception3_1_2_han0003_9841712:total images/sec: 59.61 tf_horovod_inception3_1_3//tf_horovod_inception3_1_3_han0007_9841713:total images/sec: 85.70 tf_horovod_inception3_1_4//tf_horovod_inception3_1_4_han0010_9841714:total images/sec: 113.94 tf_horovod_inception3_1_5//tf_horovod_inception3_1_5_han0014_9841715:total images/sec: 144.05 tf_horovod_inception3_1_6//tf_horovod_inception3_1_6_han0019_9841716:total images/sec: 168.36 tf_horovod_inception3_1_7//tf_horovod_inception3_1_7_han0031_9841717:total images/sec: 193.21 tf_horovod_inception3_1_8//tf_horovod_inception3_1_8_han0002_9841718:total images/sec: 227.10 tf_horovod_inception3_2_1//tf_horovod_inception3_2_1_han0044_9841723:total images/sec: 59.86 tf_horovod_inception3_2_2//tf_horovod_inception3_2_2_han0042_9841724:total images/sec: 115.65 tf_horovod_inception3_2_3//tf_horovod_inception3_2_3_han0036_9841725:total images/sec: 168.11 tf_horovod_inception3_2_4//tf_horovod_inception3_2_4_han0020_9841726:total images/sec: 231.98 tf_horovod_inception3_2_5//tf_horovod_inception3_2_5_han0025_9841727:total images/sec: 281.29 tf_horovod_inception3_2_6//tf_horovod_inception3_2_6_han0002_9841728:total images/sec: 303.14 tf_horovod_inception3_2_8//tf_horovod_inception3_2_8_han0017_9841730:total images/sec: 449.13 tf_horovod_resnet152_1_1//tf_horovod_resnet152_1_1_han0044_9841807:total images/sec: 16.90 tf_horovod_resnet152_1_10//tf_horovod_resnet152_1_10_han0019_9841815:total images/sec: 147.34 tf_horovod_resnet152_1_12//tf_horovod_resnet152_1_12_han0002_9841816:total images/sec: 171.81 tf_horovod_resnet152_1_14//tf_horovod_resnet152_1_14_han0016_9841817:total images/sec: 198.39 tf_horovod_resnet152_1_16//tf_horovod_resnet152_1_16_han0002_9841818:total images/sec: 223.94 tf_horovod_resnet152_1_2//tf_horovod_resnet152_1_2_han0042_9841808:total images/sec: 31.69 tf_horovod_resnet152_1_3//tf_horovod_resnet152_1_3_han0041_9841809:total images/sec: 44.01 tf_horovod_resnet152_1_4//tf_horovod_resnet152_1_4_han0032_9841810:total images/sec: 58.62 tf_horovod_resnet152_1_5//tf_horovod_resnet152_1_5_han0020_9841811:total images/sec: 75.68 tf_horovod_resnet152_1_6//tf_horovod_resnet152_1_6_han0031_9841812:total images/sec: 88.83 tf_horovod_resnet152_1_7//tf_horovod_resnet152_1_7_han0002_9841813:total images/sec: 98.08 tf_horovod_resnet152_1_8//tf_horovod_resnet152_1_8_han0011_9841814:total images/sec: 113.42 tf_horovod_resnet152_2_1//tf_horovod_resnet152_2_1_han0044_9841819:total images/sec: 31.19 tf_horovod_resnet152_2_14//tf_horovod_resnet152_2_14_han0002_9841829:total images/sec: 381.20 tf_horovod_resnet152_2_2//tf_horovod_resnet152_2_2_han0043_9841820:total images/sec: 59.06 tf_horovod_resnet152_2_3//tf_horovod_resnet152_2_3_han0042_9841821:total images/sec: 87.06 tf_horovod_resnet152_2_4//tf_horovod_resnet152_2_4_han0020_9841822:total images/sec: 123.09 tf_horovod_resnet152_2_5//tf_horovod_resnet152_2_5_han0025_9841823:total images/sec: 150.62 tf_horovod_resnet152_2_6//tf_horovod_resnet152_2_6_han0002_9841824:total images/sec: 177.58 tf_horovod_resnet152_2_8//tf_horovod_resnet152_2_8_han0017_9841826:total images/sec: 239.01 tf_horovod_resnet50_1_1//tf_horovod_resnet50_1_1_han0043_9841759:total images/sec: 51.27 tf_horovod_resnet50_1_10//tf_horovod_resnet50_1_10_han0002_9841767:total images/sec: 378.93 tf_horovod_resnet50_1_12//tf_horovod_resnet50_1_12_han0014_9841768:total images/sec: 455.76 tf_horovod_resnet50_1_14//tf_horovod_resnet50_1_14_han0002_9841769:total images/sec: 543.73 tf_horovod_resnet50_1_16//tf_horovod_resnet50_1_16_han0002_9841770:total images/sec: 651.41 tf_horovod_resnet50_1_2//tf_horovod_resnet50_1_2_han0043_9841760:total images/sec: 86.57 tf_horovod_resnet50_1_3//tf_horovod_resnet50_1_3_han0042_9841761:total images/sec: 128.79 tf_horovod_resnet50_1_4//tf_horovod_resnet50_1_4_han0020_9841762:total images/sec: 159.36 tf_horovod_resnet50_1_5//tf_horovod_resnet50_1_5_han0025_9841763:total images/sec: 238.30 tf_horovod_resnet50_1_6//tf_horovod_resnet50_1_6_han0002_9841764:total images/sec: 235.31 tf_horovod_resnet50_1_7//tf_horovod_resnet50_1_7_han0010_9841765:total images/sec: 280.58 tf_horovod_resnet50_1_8//tf_horovod_resnet50_1_8_han0017_9841766:total images/sec: 290.86 tf_horovod_resnet50_2_1//tf_horovod_resnet50_2_1_han0043_9841771:total images/sec: 96.62 tf_horovod_resnet50_2_2//tf_horovod_resnet50_2_2_han0042_9841772:total images/sec: 184.89 tf_horovod_resnet50_2_3//tf_horovod_resnet50_2_3_han0035_9841773:total images/sec: 240.53 tf_horovod_resnet50_2_4//tf_horovod_resnet50_2_4_han0020_9841774:total images/sec: 322.29 tf_horovod_resnet50_2_5//tf_horovod_resnet50_2_5_han0025_9841775:total images/sec: 430.72 tf_horovod_resnet50_2_6//tf_horovod_resnet50_2_6_han0020_9841776:total images/sec: 582.51 tf_horovod_resnet50_2_7//tf_horovod_resnet50_2_7_han0002_9841777:total images/sec: 483.72 tf_horovod_vgg16_1_1//tf_horovod_vgg16_1_1_han0043_9841831:total images/sec: 31.72 tf_horovod_vgg16_1_10//tf_horovod_vgg16_1_10_han0012_9841839:total images/sec: 182.85 tf_horovod_vgg16_1_12//tf_horovod_vgg16_1_12_han0002_9841840:total images/sec: 198.60 tf_horovod_vgg16_1_14//tf_horovod_vgg16_1_14_han0012_9841841:total images/sec: 225.43 tf_horovod_vgg16_1_16//tf_horovod_vgg16_1_16_han0002_9841842:total images/sec: 272.26 tf_horovod_vgg16_1_2//tf_horovod_vgg16_1_2_han0018_9841832:total images/sec: 43.32 tf_horovod_vgg16_1_3//tf_horovod_vgg16_1_3_han0042_9841833:total images/sec: 60.24 tf_horovod_vgg16_1_4//tf_horovod_vgg16_1_4_han0041_9841834:total images/sec: 77.23 tf_horovod_vgg16_1_5//tf_horovod_vgg16_1_5_han0031_9841835:total images/sec: 99.26 tf_horovod_vgg16_1_6//tf_horovod_vgg16_1_6_han0020_9841836:total images/sec: 116.97 tf_horovod_vgg16_1_7//tf_horovod_vgg16_1_7_han0031_9841837:total images/sec: 127.79 tf_horovod_vgg16_1_8//tf_horovod_vgg16_1_8_han0002_9841838:total images/sec: 150.32 tf_horovod_vgg16_2_1//tf_horovod_vgg16_2_1_han0042_9841843:total images/sec: 25.13 tf_horovod_vgg16_2_14//tf_horovod_vgg16_2_14_han0002_9841853:total images/sec: 457.16 tf_horovod_vgg16_2_2//tf_horovod_vgg16_2_2_han0043_9841844:total images/sec: 87.63 tf_horovod_vgg16_2_3//tf_horovod_vgg16_2_3_han0042_9841845:total images/sec: 123.58 tf_horovod_vgg16_2_4//tf_horovod_vgg16_2_4_han0023_9841846:total images/sec: 154.47 tf_horovod_vgg16_2_5//tf_horovod_vgg16_2_5_han0020_9841847:total images/sec: 196.85 tf_horovod_vgg16_2_6//tf_horovod_vgg16_2_6_han0023_9841848:total images/sec: 236.51 tf_horovod_vgg16_2_7//tf_horovod_vgg16_2_7_han0020_9841849:total images/sec: 262.63 tf_horovod_vgg16_2_8//tf_horovod_vgg16_2_8_han0002_9841850:total images/sec: 304.16'; $subst = "\1\t\3\t\3\t-\t\2\t\t\4,\5"; $result = preg_replace($re, $subst, $str); echo "The result of the substitution is ".$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 PHP, please visit: http://php.net/manual/en/ref.pcre.php