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

r"
"
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"(?<=[^0-9][^0-9]\s)(?P<val>[1-9]|[1-2][0-9]|3[0-3])(?=\s[^a-z\s]+\s[^a-z\s]+\s[^a-z\s]+$)" test_str = ("Increase)/Decrease in inventories -6,999,009 3,784,581\n" "Increase)/Decrease in receivables -7,393,450 3,842,984\n" "Increase/(Decrease) in payables 5,821,857 -18,006,883\n" "Grant received 0 625,255\n" "Interest paid -565,584 -1,495,877\n" "Tax paid -22,168 -21,694\n" "The annexed NOTEs form an integral part of the financial statements.\n" "36\n" "Annual Report 2012\n" "Pentamaster Corporation Berhad (5723070 ) www.pentamaster.com\n" "CONSOLIDATED STATEMENT OF CASH FLOWS\n" "FOR THE YEAR ENDED 31 DECEMBER 2012 (CONT'D)\n" "2012 2011\n" "RM RM\n" "CFI\n" "Dividend income 80,863 81,078\n" "Interest received 67,568 316,523\n" "Proceeds from disposal of property, plant and equipment/non current assets held for sale 27 28,000 48,298,000\n" "Purchase of property, plant and equipment 27 -64,624 0\n" "CFF\n" "Short term borrowings obtained/(repaid) 6,367,671 -4,757,230\n" "Net term loans repaid -3,382,414 -40,376,659\n" "Net Cash Flow -838,456 -168,122\n" "Cash and cash equivalents brought forward 5,939,258 6,147,628\n" "FOREIGN CURRENCY EXCHANGE\n" "DIFFERENCES ON OPENING BALANCE 35 -40,248\n" "Cash and cash equivalents carried forward 5,100,837 5,939,258\n" "RM RM\n" "CFO\n" "Loss)/Profit before taxation -2,083,184 2,145,073\n" "Adjustments for :0\n" "Amortisation of intangible assets 2,689,572 4,087,413\n" "Bad debts written off 7,594 0\n" "Deferred income released -1,854,722 -3,786,856\n" "Depreciation 2,855,169 2,941,851") 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