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"
"
gms

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"：\n{2}(.*?)\n*?左滑看接口.*?(i|R\d.*?) 处理器\n{2}((.*?) 独立显卡){0,1}\n{0,2}(\d*?)GB 内存\n{2}(\d*?)GB 固态硬盘.*?机身重 (.*?kg).*?(\d*?)元.*?优点！\n{2}(.*?)\n*?缺点.*?内存.(板载).*?色域覆盖.{0,1}(.*?)，平均△E.(\d{1,2}\.\d{2})，" test_str = ("聊一款走轻便+续航路线的AMD笔记本\n" "Original 猪王 笔吧评测室 Yesterday\n\n\n" "现在提到AMD，大多数人的脑海里就浮现出【性价比】这三个字。\n\n" "但我们心里都清楚，AMD有必要尝试价格更贵的笔记本电脑，不可能永远卖便宜货。\n\n\n\n" "今天的主角就是AMD的一次尝试，它没有走超低价路线，甚至不走性能路线，与之前的AMD锐龙本有很大不同。\n\n" "实际表现如何？我们来简单分析一下：\n\n" "华硕 灵耀14锐龙版\n\n\n" "左滑看接口\n\n\n" "机身左侧\n\n\n" "机身右侧\n\n\n\n" "它的配置如下：\n\n" "R7 4700U 处理器\n\n" "16GB 内存\n\n" "512GB 固态硬盘\n\n" "14英寸 1080p分辨率 100%sRGB色域 IPS屏\n\n" "电池容量 67Wh\n\n" "厚 15.7mm\n\n" "机身重 1.2kg\n\n" "适配器重 215g\n\n" "首发售价5499元\n\n\n\n" "它的优缺点如下：\n\n" "优点！\n\n" "1，触摸板与小键盘可以二合一(NumberPad 2.0技术)\n\n" "2，噪音控制较好\n\n" "3，机身+充电器比较轻便\n\n\n\n" "缺点！\n\n" "1，固态硬盘性能很弱\n\n" "2，内存延迟较高\n\n" "3，仅有一个USB-A接口\n\n\n\n" "【升级建议】\n\n" "这台笔记本电脑拆机比较麻烦，底面上方两个脚垫隐藏了螺丝，同时底面还用了一些胶进行固定，拆下时需要小心。\n\n" "双通道16GB内存能满足大部分用途的需求，内存为板载无法更换。\n\n" "固态硬盘的容量为512GB，型号为金士顿OM8PCP3，推测是OEM型号，支持PCIe3.0x4和NVMe，实测性能很弱，条件允许的话建议更换性能更好的固态硬盘。\n\n\n\n" "【购买建议】\n\n" "1，对便携与做工的要求较高\n\n" "2，对噪音控制要求较高\n\n" "3，平时不用电脑玩游戏的人\n\n" "华硕 灵耀14锐龙版的外观与酷睿版一致，机身的做工和质感都不错，键盘与边框的距离也进行了缩进，所以右Shift/Enter/Backspace等按键很长。\n\n" "值得一提的是，灵耀14的触摸板可以切换成小键盘，如果你使用外置鼠标，那么输入数字的时候能更方便。\n\n\n\n" "屏幕方面，实测色域容积为96.9%sRGB，色域覆盖为94.7%sRGB，平均△E为1.72，最大△E为3.79，在25%亮度以上支持DC调光，25%亮度以下为高频PWM调光，无论哪种调光方式均不会伤眼。\n\n" "续航方面，PCmark10续航测试成绩为12小时44分钟。(场景：现代办公)\n\n" "噪音方面，它的满载人位分贝值为43dB，比较安静。\n\n\n\n" "可能是由于供应量的关系，灵耀14锐龙版仅这一个配置在售，所以大家没得挑。\n\n" "如果你对便携性要求较高，需要一台主流价位的精致商务本，那么灵耀14锐龙版可以考虑一下。\n\n" "但这台电脑性能释放保守，且内存延迟达到116.1ns，所以它并不适合玩游戏，也不适合做一些性能要求较高的专业软件。\n\n\n\n" "【猪王的良心结语】\n\n" "上图是华硕 灵耀14锐龙版的拆机实拍图，单热管单风扇的组合，和酷睿版一致。\n\n" "室温25.5℃\n\n" "反射率1.00\n\n" "BIOS版本：UX425IA.301\n\n\n\n" "针对无独显的轻薄本，我们使用负载较低的Stress CPU进行压力测试。\n\n" "在满载状态下，CPU温度最高69℃，功耗13.8W左右，频率维持在3.0GHz。\n\n" "这台电脑通过System Temperature Tracking V2（STT V2）对功耗进行控制，不少搭载APU的机器也使用该机制。\n\n" "其中用于触发STT V2的一个温度参数设定偏低，所以负载上来后，功耗会一直降低直到温度符合设定值。\n\n\n" "左滑看背面温度\n\n\n" "背面温度\n\n\n\n" "表面温度如上图所示，键盘键帽温度最高为42.9℃，WASD键位区域在38℃附近，方向键31.2℃，左腕托33.1℃，背面中心点37℃。\n\n" "总的来说，灵耀14锐龙版的散热表现一般，CPU核心温度很低，性能也低于行业均值，带来的是较低的满载噪音。\n\n" " \n\n" "最近针对这台电脑的性能释放争议较多，在我看来，性能释放保守的轻薄本≠垃圾，一台核显轻薄本，其本身的定位又是办公+静音，拿它跑游戏是舍本逐末的行为。\n\n" "如果你要玩游戏、要性能，那你应该买游戏本，或者高性能取向的轻薄本。\n\n" "而至于这台华硕 灵耀14锐龙版，如果它能将硬盘和散热规格做好一点，相信市场表现也会更好一些。\n\n\n" "猪王二手店\n\n\n" "猪王新机店\n\n\n" "加入笔吧\n\n" "【笔吧评测室招商计划启动啦】\n\n" "【广告投放请点我联系】\n\n\n" "Scan to Follow") matches = re.finditer(regex, test_str, re.MULTILINE | re.DOTALL) 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