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

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"(.*(?!\s))(?:(?<!\s\s)\:\s+)((?:[\-\+])?\d+\.\d+|\w+$|[\-\+]\d+|\w+\s\d+)" test_str = ("Beam Number : 2\n" "Beam Name : CCW\n" "Original MU : 1995.39040729\n\n" "Logging Scale : IEC 1217\n" "X1 (Cms): -2.50\n" "X2 (Cms): +2.20\n" "Y1 (Cms): -2.60\n" "Y2 (Cms): +2.50\n" "Gantry Rotation Angle (deg): 87.73\n" "Energy : 6x\n" "MU1 : 1007.63\n" "MU2 : 1009.05\n" "Radiation Time (mins): 1.6807\n" "DoseRate (MU/min): 598.32\n" "PFN High Voltage Power Supply Current (A): 1.908875\n" "PFN Actual Voltage (KV): 18.21791\n" "RF Driver Voltage (V): 4.365\n" "RF Forward Power (W): 1.516418\n" "AFC Error (V): -0.000601778\n" "Gun Current (A): 0.3430939\n" "Gun High Voltage (V): -14965\n" "Gun Grid Voltage (V): 97.55565\n" "Gun Filament Step Voltage (V): 5.300003\n" "Gun Filament Voltage (V): 5.405273\n" "Bend Magnet Current (A): 16.18042\n" "Bend Magnet Voltage (V): 2.283325\n" "Accelerator Solenoid Current (A): 34.95636\n" "Klystron Solenoid Current (A): 34.95789\n" "Radial Symmetry (%): 0.00045321\n" "Transverse Symmetry (%): 0.00044355\n" "Target Current (nC): 315.4927\n" "Buncher Radial Current (A): 0.005020142\n" "Buncher Transverse Current (A): -0.06005859\n" "Angle Radial Current (A): 0.005279541\n" "Angle Transverse Current (A): 0.06143188\n" "Position Radial Current (A): -0.8885803\n" "Position Transverse Current (A): -0.5808258\n" "Trim : (A) -0.06399536\n" "Accelerator Vacion Current (uA): 0.009002686\n" "Positive 5V dc: 4.993916\n" "Positive 24V dc: 24.4706\n" "Analog Negative 5V dc: 5.054981\n" "Analog Positive 5V dc: 4.97241\n" "Negative 12V dc: 12.24357\n" "Positive 3V dc: 3.303525\n" "Node Power Supply Voltage (V): 24.58121\n" "Water Level : Normal\n" "City Water Temperature (deg C): 20.54332\n" "Internal Water Supply Temperature (deg C): 40.51909\n" "Gas Pressure (PSI): 32.3421") 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