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

/
/
g

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"(?<code1>class=\"relativetime\">)(?<code2>.+)(?<code3><\/span>)" test_str = ("<!DOCTYPE html>\n" "<html>\n" "<head>\n\n" " <title>Newest Questions - Page 44 - Electrical Engineering Stack Exchange</title>\n" " <link rel=\"shortcut icon\" href=\"//cdn.sstatic.net/electronics/img/favicon.ico\">\n" " <link rel=\"apple-touch-icon image_src\" href=\"//cdn.sstatic.net/electronics/img/apple-touch-icon.png\">\n" " <link rel=\"search\" type=\"application/opensearchdescription+xml\" title=\"Electrical Engineering Stack Exchange\" href=\"/opensearch.xml\">\n\n" " <script type=\"text/javascript\" src=\"//ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js\"></script>\n" " <script type=\"text/javascript\" src=\"//cdn.sstatic.net/js/stub.js?v=5d233283ca8d\"></script>\n" " <link rel=\"stylesheet\" type=\"text/css\" href=\"//cdn.sstatic.net/electronics/all.css?v=672ddec9ce04\">\n\n\n" " <script type=\"text/x-mathjax-config\">\n" " MathJax.Hub.Config({\"HTML-CSS\": { preferredFont: \"TeX\", availableFonts: [\"STIX\",\"TeX\"], linebreaks: { automatic:true }, EqnChunk: (MathJax.Hub.Browser.isMobile ? 10 : 50) },\n" " tex2jax: { inlineMath: [ [\"\\\\$\", \"\\\\$\"] ], displayMath: [ [\"$$\",\"$$\"], [\"\\\\[\", \"\\\\]\"] ], processEscapes: true, ignoreClass: \"tex2jax_ignore|dno\" },\n" " TeX: { noUndefined: { attributes: { mathcolor: \"red\", mathbackground: \"#FFEEEE\", mathsize: \"90%\" } }, Macros: { href: \"{}\" } },\n" " messageStyle: \"none\"\n" " });\n" " </script>\n" " <script type=\"text/javascript\" src=\"http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS_HTML\"></script>\n\n" " <script type=\"text/javascript\">\n" " StackExchange.ready(function () {\n" " StackExchange.realtime.init('sockets.ny.stackexchange.com');\n" " StackExchange.realtime.subscribeToInboxNotifications();\n" " StackExchange.realtime.subscribeToReputationNotifications('135');\n" " });\n" " </script>\n" " <script type=\"text/javascript\">\n" " StackExchange.init({\"stackAuthUrl\":\"https://stackauth.com\",\"serverTime\":1377686850,\"styleCode\":true,\"enableUserHovercards\":true,\"site\":{\"name\":\"Electrical Engineering Stack Exchange\",\"description\":\"Q&A for electronics and electrical engineering professionals, students, and enthusiasts\",\"isNoticesTabEnabled\":true,\"recaptchaPublicKey\":\"6LdsB7sSAAAAAAzjgEF_Hd8vXv-C42sa_KyofaGR\",\"enableSocialMediaInSharePopup\":true},\"user\":{\"fkey\":\"964caaf8350dc8ae69af722ba29b4a1d\",\"isAnonymous\":true}});\n" " StackExchange.using.setCacheBreakers({\"js/prettify-full.js\":\"6c261bebf56a\",\"js/moderator.js\":\"ed7a8238b2f8\",\"js/full-anon.js\":\"5f9bf5810297\",\"js/full.js\":\"027ac5ea264e\",\"js/wmd.js\":\"cff10cca4fd9\",\"js/third-party/jquery.autocomplete.min.js\":\"e5f01e97f7c3\",\"js/mobile.js\":\"82a79dbb7259\",\"js/help.js\":\"6e6623243cf6\",\"js/tageditor.js\":\"450c9e8426fc\",\"js/tageditornew.js\":\"b6c68ad4c7dd\",\"js/inline-tag-editing.js\":\"8e84e8a137f7\",\"js/revisions.js\":\"d3e781ee5528\",\"js/review.js\":\"947758ba83ea\",\"js/tagsuggestions.js\":\"aa48ef6154df\",\"js/post-validation.js\":\"bb996020492a\",\"js/explore-qlist.js\":\"1c5bbd79b562\",\"js/events.js\":\"27a33f0b2cad\"});\n" " StackExchange.using.setCacheBreakers({\"js/mathjax-editing.js\":\"6da1b6cfe19f\",\"js/external-editor.js\":\"51c0a8d46d29\"});\n" " </script>\n" " <script type=\"text/javascript\">\n" " StackExchange.using(\"gps\", function() {\n" " StackExchange.gps.init(true);\n" " });\n" " </script>\n\n" " <script type=\"text/javascript\">\n" " StackExchange.ready(function () {\n" " $('#nav-tour').click(function () {\n" " StackExchange.using(\"gps\", function() {\n" " StackExchange.gps.track(\"aboutpage.click\", { aboutclick_location: \"headermain\" }, true);\n" " });\n" " });\n" " });\n" " </script>\n" "</head>\n" "<body class=\"questions-page\">\n" " <noscript><div id=\"noscript-padding\"></div></noscript>\n" " <div id=\"notify-container\"></div>\n" " <div id=\"overlay-header\"></div>\n" " <div id=\"custom-header\"></div>\n\n" " <div class=\"container\">\n" " <div id=\"header\" class=headeranon>\n" " <div id=\"portalLink\">\n" " <a class=\"genu\" href=\"http://stackexchange.com\" onclick=\"StackExchange.ready(function(){genuwine.click();});return false;\">Stack Exchange</a>\n" " </div>\n" " <div id=\"topbar\">\n" " <div id=\"hlinks\">\n\n" "<span id=\"hlinks-user\"></span>\n" "<span id=\"hlinks-nav\"> <a href=\"/users/login?returnurl=%2fquestions%3fpage%3d44%26sort%3dnewest\">sign up</a>\n\n" " <span class=\"lsep\">|</span>\n" " <a href=\"/users/login?returnurl=%2fquestions%3fpage%3d44%26sort%3dnewest\">log in</a>\n\n" " <span class=\"lsep\">|</span>\n" "</span>\n" "<span id=\"hlinks-custom\"></span>\n" " </div>\n" " <div id=\"hsearch\">\n" " <form id=\"search\" action=\"/search\" method=\"get\" autocomplete=\"off\">\n" " <div>\n" " <input autocomplete=\"off\" name=\"q\" class=\"textbox\" placeholder=\"search\" tabindex=\"1\" type=\"text\" maxlength=\"240\" size=\"28\" value=\"\">\n" " </div>\n" " </form>\n" " </div>\n" " </div>\n" " <br class=\"cbt\">\n" " <div id=\"hlogo\">\n" " <a href=\"/\">\n" " Electrical Engineering\n" " </a>\n" " </div>\n" " <div id=\"hmenus\">\n" " <div class=\"nav mainnavs mainnavsanon\">\n" " <ul>\n" " <li class=\"youarehere\"><a id=\"nav-questions\" href=\"/questions\">Questions</a></li>\n" " <li><a id=\"nav-tags\" href=\"/tags\">Tags</a></li>\n" " <li><a id=\"nav-tour\" href=\"/about\">Tour</a></li>\n" " <li><a id=\"nav-users\" href=\"/users\">Users</a></li>\n" " </ul>\n" " </div>\n" " <div class=\"nav askquestion\">\n" " <ul>\n" " <li>\n" " <a id=\"nav-askquestion\" href=\"/questions/ask\">Ask Question</a>\n" " </li>\n" " </ul>\n" " </div>\n" " </div>\n" " </div>\n\n\n\n\n" " <div id=\"content\">\n\n" "<div id=\"mainbar\">\n" " <div class=\"subheader\">\n" " <h1 id=\"h-all-questions\">All Questions</h1>\n" " <div id=\"tabs\">\n" "<a class=\"youarehere\" href=\"/questions?sort=newest\" title=\"the most recently asked questions\">newest</a>\n" "<a href=\"/questions?sort=featured\" title=\"questions with open bounties\"><span class='bounty-indicator-tab'>3</span>featured</a>\n" "<a href=\"/questions?sort=frequent\" title=\"questions with the most links\">frequent</a>\n" "<a href=\"/questions?sort=votes\" title=\"questions with the most votes\">votes</a>\n" "<a href=\"/questions?sort=active\" title=\"questions that have recent activity\">active</a>\n" "<a href=\"/questions?sort=unanswered\" title=\"questions that have no upvoted answers\">unanswered</a>\n\n" " </div>\n" " </div>\n\n" " <div id=\"questions\">\n\n" "<div class=\"question-summary\" id=\"question-summary-78358\">\n" " <div class=\"statscontainer\">\n" " <div class=\"statsarrow\"></div>\n" " <div class=\"stats\">\n" " <div class=\"vote\">\n" " <div class=\"votes\">\n" " <span class=\"vote-count-post \"><strong>-1</strong></span>\n" " <div class=\"viewcount\">votes</div>\n" " </div>\n" " </div>\n" " <div class=\"status answered\">\n" " <strong>1</strong>answer\n" " </div>\n" " </div>\n\n\n\n" "<div class=\"views \" title=\"34 views\">\n" " 34 views\n" "</div>\n" " </div>\n" " <div class=\"summary\">\n" " <h3><a href=\"/questions/78358/controlling-2-kw-230v-infra-red-short-wave-heaters-using-electronic-device\" class=\"question-hyperlink\">controlling 2 kw,230v- infra red short wave heaters using electronic device</a></h3>\n" " <div class=\"excerpt\">\n" " i want to control infra red short wave heaters 230v,2kw, with some electronic device,\n" "it is an open loop system,where i want to give analog signal to heater from 0 to 100% .\n" "i cant take Thermocouple ...\n" " </div>\n\n" " <div class=\"tags t-voltage-regulator t-solid-state-relay t-dimming\">\n" " <a href=\"/questions/tagged/voltage-regulator\" class=\"post-tag\" title=\"show questions tagged 'voltage-regulator'\" rel=\"tag\">voltage-regulator</a> <a href=\"/questions/tagged/solid-state-relay\" class=\"post-tag\" title=\"show questions tagged 'solid-state-relay'\" rel=\"tag\">solid-state-relay</a> <a href=\"/questions/tagged/dimming\" class=\"post-tag\" title=\"show questions tagged 'dimming'\" rel=\"tag\">dimming</a>\n\n" " </div>\n" " <div class=\"started fr\">\n\n\n" " <div class=\"user-info \">\n" " <div class=\"user-action-time\">\n\n\n" " asked <span title=\"2013-08-08 10:06:07Z\" class=\"relativetime\">Aug 8 at 10:06</span>\n" " </div>\n" " <div class=\"user-gravatar32\">\n" " <a href=\"/users/27245/user27245\"><div class=\"\"><img src=\"https://www.gravatar.com/avatar/73e6c66117a190c5cc03a90caf569aae?s=32&d=identicon&r=PG\" alt=\"\" width=\"32\" height=\"32\"></div></a>\n" " </div>\n" " <div class=\"user-details\">\n" " <a href=\"/users/27245/user27245\">user27245</a><br>\n" " <span class=\"reputation-score\" title=\"reputation score\" dir=\"ltr\">1</span>\n" " </div>\n" " </div>\n\n" " </div>\n" " </div>\n" "</div>\n\n" "<div class=\"question-summary\" id=\"question-summary-78355\">\n" " <div class=\"statscontainer\">\n" " <div class=\"statsarrow\"></div>\n" " <div class=\"stats\">\n" " <div class=\"vote\">\n" " <div class=\"votes\">\n" " <span class=\"vote-count-post \"><strong>0</strong></span>\n" " <div class=\"viewcount\">votes</div>\n" " </div>\n" " </div>\n" " <div class=\"status unanswered\">\n" " <strong>0</strong>answers\n" " </div>\n" " </div>\n\n\n\n" "<div class=\"views \" title=\"47 views\">\n" " 47 views\n" "</div>\n" " </div>\n" " <div class=\"summary\">\n" " <h3><a href=\"/questions/78355/how-to-synchronize-internal-rtc-to-computer-time-and-date\" class=\"question-hyperlink\">how to synchronize internal RTC to computer time and date</a></h3>\n" " <div class=\"excerpt\">\n" " i am using pic18f67k22 controller.i already configure and initialize internal RTC. But i want start RTC to computer time.so how i can synchronize pic RTC to computer.i have one computer application ...\n" " </div>\n\n" " <div class=\"tags t-microcontroller t-pic t-rtc\">\n" " <a href=\"/questions/tagged/microcontroller\" class=\"post-tag\" title=\"show questions tagged 'microcontroller'\" rel=\"tag\">microcontroller</a> <a href=\"/questions/tagged/pic\" class=\"post-tag\" title=\"show questions tagged 'pic'\" rel=\"tag\">pic</a> <a href=\"/questions/tagged/rtc\" class=\"post-tag\" title=\"show questions tagged 'rtc'\" rel=\"tag\">rtc</a>\n\n" " </div>\n" " <div class=\"started fr\">\n\n\n" " <div class=\"user-info \">\n" " <div class=\"user-action-time\">\n\n\n" " asked <span title=\"2013-08-08 08:52:58Z\" class=\"relativetime\">Aug 8 at 8:52</span>\n" " </div>\n" " <div class=\"user-gravatar32\">\n" " <a href=\"/users/23841/shail-korat\"><div class=\"\"><img src=\"https://www.gravatar.com/avatar/649adca335821feacbd54299440806f2?s=32&d=identicon&r=PG\" alt=\"\" width=\"32\" height=\"32\"></div></a>\n" " </div>\n" " <div class=\"user-details\">\n" " <a href=\"/users/23841/shail-korat\">shail korat</a><br>\n" " <span class=\"reputation-score\" title=\"reputation score\" dir=\"ltr\">23</span><span title=\"6 bronze badges\"><span class=\"badge3\"></span><span class=\"badgecount\">6</span></span>\n" " </div>\n" " </div>\n\n" " </div>\n" " </div>\n" "</div>\n\n" "<div class=\"question-summary\" id=\"question-summary-78353\">\n" " <div class=\"statscontainer\">\n" " <div class=\"statsarrow\"></div>\n" " <div class=\"stats\">\n" " <div class=\"vote\">\n" " <div class=\"votes\">\n" " <span class=\"vote-count-post \"><strong>1</strong></span>\n" " <div class=\"viewcount\">vote</div>\n" " </div>\n" " </div>\n" " <div class=\"status answered-accepted\">\n" " <strong>1</strong>answer\n" " </div>\n" " </div>\n\n\n\n" "<div class=\"views \" title=\"46 views\">\n" " 46 views\n" "</div>\n" " </div>\n" " <div class=\"summary\">\n" " <h3><a href=\"/questions/78353/spi-interfacing-using-serial-port-or-usb\" class=\"question-hyperlink\">SPI Interfacing using Serial Port or USB</a></h3>\n" " <div class=\"excerpt\">\n" " I have a nRF24L01+ module from Nordic Semiconductors. It has SPI interface. My laptop has USB ports and I have a Serial Port (Using a USB-to-Serial_Port adapter). What is the best possible solution to ...\n" " </div>\n\n" " <div class=\"tags t-usb t-serial t-spi t-interface\">\n" " <a href=\"/questions/tagged/usb\" class=\"post-tag\" title=\"show questions tagged 'usb'\" rel=\"tag\">usb</a> <a href=\"/questions/tagged/serial\" class=\"post-tag\" title=\"show questions tagged 'serial'\" rel=\"tag\">serial</a> <a href=\"/questions/tagged/spi\" class=\"post-tag\" title=\"show questions tagged 'spi'\" rel=\"tag\">spi</a> <a href=\"/questions/tagged/interface\" class=\"post-tag\" title=\"show questions tagged 'interface'\" rel=\"tag\">interface</a>\n\n" " </div>\n" " <div class=\"started fr\">\n\n\n" " <div class=\"user-info \">\n" " <div class=\"user-action-time\">\n\n\n" " asked <span title=\"2013-08-08 08:32:08Z\" class=\"relativetime\">Aug 8 at 8:32</span>\n" " </div>\n" " <div class=\"user-gravatar32\">\n" " <a href=\"/users/7329/subin-sebastian\"><div class=\"\"><img src=\"https://www.gravatar.com/avatar/b3b512420352799f21d1e7933b59b9ed?s=32&d=identicon&r=PG\" alt=\"\" width=\"32\" height=\"32\"></div></a>\n" " </div>\n" " <div class=\"user-details\">\n" " <a href=\"/users/7329/subin-sebastian\">Subin Sebastian</a><br>\n" " <span class=\"reputation-score\" title=\"reputation score\" dir=\"ltr\">211</span><span title=\"1 silver badge\"><span class=\"badge2\"></span><span class=\"badgecount\">1</span></span><span title=\"7 bronze badges\"><span class=\"badge3\"></span><span class=\"badgecount\">7</span></span>\n" " </div>\n" " </div>\n\n" " </div>\n" " </div>\n" "</div>\n\n" "<div class=\"question-summary\" id=\"question-summary-78351\">\n" " <div class=\"statscontainer\">\n" " <div class=\"statsarrow\"></div>\n" " <div class=\"stats\">\n" " <div class=\"vote\">\n" " <div class=\"votes\">\n" " <span class=\"vote-count-post \"><strong>2</strong></span>\n" " <div class=\"viewcount\">votes</div>\n" " </div>\n" " </div>\n" " <div class=\"status answered-accepted\">\n" " <strong>2</strong>answers\n" " </div>\n" " </div>\n\n\n\n" "<div class=\"views \" title=\"54 views\">\n" " 54 views\n" "</div>\n" " </div>\n" " <div class=\"summary\">\n" " <h3><a href=\"/questions/78351/trouble-on-understanding-alu-2-bit-design\" class=\"question-hyperlink\">Trouble on understanding ALU 2-bit design</a></h3>\n" " <div class=\"excerpt\">\n" " I'm new to this site and I'm pretty \"noobish\" to electrical engineering coming from a software engineering background I was hoping someone could help me understand this design a bit. I've highlighted ...\n" " </div>\n\n" " <div class=\"tags t-alu\">\n" " <a href=\"/questions/tagged/alu\" class=\"post-tag\" title=\"show questions tagged 'alu'\" rel=\"tag\">alu</a>\n\n" " </div>\n" " <div class=\"started fr\">\n\n\n" " <div class=\"user-info \">\n" " <div class=\"user-action-time\">\n\n\n" " asked <span title=\"2013-08-08 08:20:46Z\" class=\"relativetime\">Aug 8 at 8:20</span>\n" " </div>\n" " <div class=\"user-gravatar32\">\n" " <a href=\"/users/27251/thecodemonsters\"><div class=\"\"><img src=\"https://www.gravatar.com/avatar/b02a007bf995a0986bd3c55d6b5bc3e6?s=32&d=identicon&r=PG\" alt=\"\" width=\"32\" height=\"32\"></div></a>\n" " </div>\n" " <div class=\"user-details\">\n" " <a href=\"/users/27251/thecodemonsters\">theCodeMonsters</a><br>\n" " <span class=\"reputation-score\" title=\"reputation score\" dir=\"ltr\">13</span><span title=\"2 bronze badges\"><span class=\"badge3\"></span><span class=\"badgecount\">2</span></span>\n" " </div>\n" " </div>\n\n" " </div>\n" " </div>\n" "</div>\n\n" "<div class=\"question-summary\" id=\"question-summary-78348\">\n" " <div class=\"statscontainer\">\n" " <div class=\"statsarrow\"></div>\n" " <div class=\"stats\">\n" " <div class=\"vote\">\n" " <div class=\"votes\">\n" " <span class=\"vote-count-post \"><strong>3</strong></span>\n" " <div class=\"viewcount\">votes</div>\n" " </div>\n" " </div>\n" " <div class=\"status answered\">\n" " <strong>1</strong>answer\n" " </div>\n" " </div>\n\n\n\n" "<div class=\"views \" title=\"57 views\">\n" " 57 views\n" "</div>\n" " </div>\n" " <div class=\"summary\">\n" " <h3><a href=\"/questions/78348/small-max-5x5-mm-connector-panel-mount-for-asyncronous-serial-interface\" class=\"question-hyperlink\">Small (max 5x5 mm) connector, panel mount, for asyncronous serial interface?</a></h3>\n" " <div class=\"excerpt\">\n" " I opened a small router and hooked up 2 wires on the PCB (to catch the serial data). That works fine.\n\n" "Now I'm looking for a way to make a small (tiny) connector in the enclosure, so for future use i ...\n" " </div>\n\n" " <div class=\"tags t-pcb t-connector t-cases t-mount\">\n" " <a href=\"/questions/tagged/pcb\" class=\"post-tag\" title=\"show questions tagged 'pcb'\" rel=\"tag\">pcb</a> <a href=\"/questions/tagged/connector\" class=\"post-tag\" title=\"show questions tagged 'connector'\" rel=\"tag\">connector</a> <a href=\"/questions/tagged/cases\" class=\"post-tag\" title=\"show questions tagged 'cases'\" rel=\"tag\">cases</a> <a href=\"/questions/tagged/mount\" class=\"post-tag\" title=\"show questions tagged 'mount'\" rel=\"tag\">mount</a>\n\n" " </div>\n" " <div class=\"started fr\">\n\n\n" " <div class=\"user-info \">\n" " <div class=\"user-action-time\">\n\n\n" " asked <span title=\"2013-08-08 07:20:56Z\" class=\"relativetime\">Aug 8 at 7:20</span>\n" " </div>\n" " <div class=\"user-gravatar32\">\n" " <a href=\"/users/8524/rogier\"><div class=\"\"><img src=\"https://www.gravatar.com/avatar/181219cd20b8036ef8ec45b94aed6474?s=32&d=identicon&r=PG\" alt=\"\" width=\"32\" height=\"32\"></div></a>\n" " </div>\n" " <div class=\"user-details\">\n" " <a href=\"/users/8524/rogier\">Rogier</a><br>\n" " <span class=\"reputation-score\" title=\"reputation score\" dir=\"ltr\">165</span><span title=\"6 bronze badges\"><span class=\"badge3\"></span><span class=\"badgecount\">6</span></span>\n" " </div>\n" " </div>\n\n" " </div>\n" " </div>\n" "</div>\n\n" "<div class=\"question-summary\" id=\"question-summary-78345\">\n" " <div class=\"statscontainer\">\n" " <div class=\"statsarrow\"></div>\n" " <div class=\"stats\">\n" " <div class=\"vote\">\n" " <div class=\"votes\">\n" " <span class=\"vote-count-post \"><strong>4</strong></span>\n" " <div class=\"viewcount\">votes</div>\n" " </div>\n" " </div>\n" " <div class=\"status answered-accepted\">\n" " <strong>1</strong>answer\n" " </div>\n" " </div>\n\n\n\n" "<div class=\"views \" title=\"69 views\">\n" " 69 views\n" "</div>\n" " </div>\n" " <div class=\"summary\">\n" " <h3><a href=\"/questions/78345/what-happened-to-the-to-3-package\" class=\"question-hyperlink\">What happened to the TO-3 package?</a></h3>\n" " <div class=\"excerpt\">\n" " TO-3 used to be a common package for power transistors, but you don't see them much anymore. It can't be just because of SMT, TO-220 is still much in use. TO-3 has a much lower thermal resistance than ...\n" " </div>\n\n" " <div class=\"tags t-packages\">\n" " <a href=\"/questions/tagged/packages\" class=\"post-tag\" title=\"show questions tagged 'packages'\" rel=\"tag\">packages</a>\n\n" " </div>\n" " <div class=\"started fr\">\n\n\n" " <div class=\"user-info \">\n" " <div class=\"user-action-time\">\n\n\n" " asked <span title=\"2013-08-08 07:05:21Z\" class=\"relativetime\">Aug 8 at 7:05</span>\n" " </div>\n" " <div class=\"user-gravatar32\">\n" " <a href=\"/users/27167/radagast\"><div class=\"\"><img src=\"https://www.gravatar.com/avatar/294b3e797acb485f50878567a54bfec8?s=32&d=identicon&r=PG\" alt=\"\" width=\"32\" height=\"32\"></div></a>\n" " </div>\n" " <div class=\"user-details\">\n" " <a href=\"/users/27167/radagast\">radagast</a><br>\n" " <span class=\"reputation-score\" title=\"reputation score\" dir=\"ltr\">334</span><span title=\"1 silver badge\"><span class=\"badge2\"></span><span class=\"badgecount\">1</span></span><span title=\"11 bronze badges\"><span class=\"badge3\"></span><span class=\"badgecount\">11</span></span>\n" " </div>\n" " </div>\n\n" " </div>\n" " </div>\n" "</div>\n\n" "<div class=\"question-summary\" id=\"question-summary-78337\">\n" " <div class=\"statscontainer\">\n" " <div class=\"statsarrow\"></div>\n" " <div class=\"stats\">\n" " <div class=\"vote\">\n" " <div class=\"votes\">\n" " <span class=\"vote-count-post \"><strong>16</strong></span>\n" " <div class=\"viewcount\">votes</div>\n" " </div>\n" " </div>\n" " <div class=\"status answered-accepted\">\n" " <strong>2</strong>answers\n" " </div>\n" " </div>\n\n\n\n" "<div class=\"views \" title=\"431 views\">\n" " 431 views\n" "</div>\n" " </div>\n" " <div class=\"summary\">\n" " <h3><a href=\"/questions/78337/which-way-does-electricity-power-a-circuit\" class=\"question-hyperlink\">Which way does electricity power a circuit?</a></h3>\n" " <div class=\"excerpt\">\n" " Working with some circuits this summer, I ran into what everyone eventually does: Current flows from + to - despite the electrons flowing (well, bumping into eachother) from - to +. I understand the ...\n" " </div>\n\n" " <div class=\"tags t-power-supply t-current t-analog\">\n" " <a href=\"/questions/tagged/power-supply\" class=\"post-tag\" title=\"show questions tagged 'power-supply'\" rel=\"tag\">power-supply</a> <a href=\"/questions/tagged/current\" class=\"post-tag\" title=\"show questions tagged 'current'\" rel=\"tag\">current</a> <a href=\"/questions/tagged/analog\" class=\"post-tag\" title=\"show questions tagged 'analog'\" rel=\"tag\">analog</a>\n\n" " </div>\n" " <div class=\"started fr\">\n\n\n" " <div class=\"user-info \">\n" " <div class=\"user-action-time\">\n\n\n" " asked <span title=\"2013-08-08 04:00:29Z\" class=\"relativetime\">Aug 8 at 4:00</span>\n" " </div>\n" " <div class=\"user-gravatar32\">\n" " <a href=\"/users/27243/tom\"><div class=\"\"><img src=\"https://www.gravatar.com/avatar/bfc2bcb561dd6949178afc5306c1fb25?s=32&d=identicon&r=PG\" alt=\"\" width=\"32\" height=\"32\"></div></a>\n" " </div>\n" " <div class=\"user-details\">\n" " <a href=\"/users/27243/tom\">Tom</a><br>\n" " <span class=\"reputation-score\" title=\"reputation score\" dir=\"ltr\">81</span><span title=\"4 bronze badges\"><span class=\"badge3\"></span><span class=\"badgecount\">4</span></span>\n" " </div>\n" " </div>\n\n" " </div>\n" " </div>\n" "</div>\n\n" "<div class=\"question-summary\" id=\"question-summary-78336\">\n" " <div class=\"statscontainer\">\n" " <div class=\"statsarrow\"></div>\n" " <div class=\"stats\">\n" " <div class=\"vote\">\n" " <div class=\"votes\">\n" " <span class=\"vote-count-post \"><strong>1</strong></span>\n" " <div class=\"viewcount\">vote</div>\n" " </div>\n" " </div>\n" " <div class=\"status answered\">\n" " <strong>2</strong>answers\n" " </div>\n" " </div>\n\n\n\n" "<div class=\"views \" title=\"115 views\">\n" " 115 views\n" "</div>\n" " </div>\n" " <div class=\"summary\">\n" " <h3><a href=\"/questions/78336/using-relay-with-microcontroller\" class=\"question-hyperlink\">Using Relay With Microcontroller</a></h3>\n" " <div class=\"excerpt\">\n" " I have created a boost converter which boost 12v to 60v. I want to be able to pulse this voltage under water. I would like to have only the positive lead (Vout from boost) to come off the boost ...\n" " </div>\n\n" " <div class=\"tags t-microcontroller t-relay\">\n" " <a href=\"/questions/tagged/microcontroller\" class=\"post-tag\" title=\"show questions tagged 'microcontroller'\" rel=\"tag\">microcontroller</a> <a href=\"/questions/tagged/relay\" class=\"post-tag\" title=\"show questions tagged 'relay'\" rel=\"tag\">relay</a>\n\n" " </div>\n" " <div class=\"started fr\">\n\n\n" " <div class=\"user-info \">\n" " <div class=\"user-action-time\">\n\n\n" " asked <span title=\"2013-08-08 03:56:44Z\" class=\"relativetime\">Aug 8 at 3:56</span>\n" " </div>\n" " <div class=\"user-gravatar32\">\n" " <a href=\"/users/27242/wallace\"><div class=\"\"><img src=\"https://www.gravatar.com/avatar/ea5a17f0b7d6efa25f118ade0a0db9d5?s=32&d=identicon&r=PG\" alt=\"\" width=\"32\" height=\"32\"></div></a>\n" " </div>\n" " <div class=\"user-details\">\n" " <a href=\"/users/27242/wallace\">Wallace</a><br>\n" " <span class=\"reputation-score\" title=\"reputation score\" dir=\"ltr\">58</span><span title=\"7 bronze badges\"><span class=\"badge3\"></span><span class=\"badgecount\">7</span></span>\n" " </div>\n" " </div>\n\n" " </div>\n" " </div>\n" "</div>\n\n" "<div class=\"question-summary\" id=\"question-summary-78329\">\n" " <div class=\"statscontainer\">\n" " <div class=\"statsarrow\"></div>\n" " <div class=\"stats\">\n" " <div class=\"vote\">\n" " <div class=\"votes\">\n" " <span class=\"vote-count-post \"><strong>0</strong></span>\n" " <div class=\"viewcount\">votes</div>\n" " </div>\n" " </div>\n" " <div class=\"status answered\">\n" " <strong>2</strong>answers\n" " </div>\n" " </div>\n\n\n\n" "<div class=\"views \" title=\"48 views\">\n" " 48 views\n" "</div>\n" " </div>\n" " <div class=\"summary\">\n" " <h3><a href=\"/questions/78329/how-to-measure-the-current-from-ac-dc-supplier\" class=\"question-hyperlink\">how to measure the current from AC-DC supplier?</a></h3>\n" " <div class=\"excerpt\">\n" " I started to learn the AC/DC circuit some times ago. I don't have much experience. But from this semester on, I have some chances to practice it in lab by working on some project. I got a AC/DC power ...\n" " </div>\n\n" " <div class=\"tags t-power-supply t-dc\">\n" " <a href=\"/questions/tagged/power-supply\" class=\"post-tag\" title=\"show questions tagged 'power-supply'\" rel=\"tag\">power-supply</a> <a href=\"/questions/tagged/dc\" class=\"post-tag\" title=\"show questions tagged 'dc'\" rel=\"tag\">dc</a>\n\n" " </div>\n" " <div class=\"started fr\">\n\n\n" " <div class=\"user-info \">\n" " <div class=\"user-action-time\">\n\n\n" " asked <span title=\"2013-08-08 02:05:53Z\" class=\"relativetime\">Aug 8 at 2:05</span>\n" " </div>\n" " <div class=\"user-gravatar32\">\n" " <a href=\"/users/17060/user1285419\"><div class=\"\"><img src=\"https://www.gravatar.com/avatar/08ee68b20a4eceff26f7eee99b708c08?s=32&d=identicon&r=PG\" alt=\"\" width=\"32\" height=\"32\"></div></a>\n" " </div>\n" " <div class=\"user-details\">\n" " <a href=\"/users/17060/user1285419\">user1285419</a><br>\n" " <span class=\"reputation-score\" title=\"reputation score\" dir=\"ltr\">165</span><span title=\"5 bronze badges\"><span class=\"badge3\"></span><span class=\"badgecount\">5</span></span>\n" " </div>\n" " </div>\n\n" " </div>\n" " </div>\n" "</div>\n\n" "<div class=\"question-summary\" id=\"question-summary-78328\">\n" " <div class=\"statscontainer\">\n" " <div class=\"statsarrow\"></div>\n" " <div class=\"stats\">\n" " <div class=\"vote\">\n" " <div class=\"votes\">\n" " <span class=\"vote-count-post \"><strong>0</strong></span>\n" " <div class=\"viewcount\">votes</div>\n" " </div>\n" " </div>\n" " <div class=\"status answered\">\n" " <strong>1</strong>answer\n" " </div>\n" " </div>\n\n\n\n" "<div class=\"views \" title=\"86 views\">\n" " 86 views\n" "</div>\n" " </div>\n" " <div class=\"summary\">\n" " <h3><a href=\"/questions/78328/reducing-capacitance-of-a-wire\" class=\"question-hyperlink\">Reducing capacitance of a wire</a></h3>\n" " <div class=\"excerpt\">\n" " Given a wire and a piece of foil wired to a bread board, is it possible using capacitors wired in series (or some other method) to significantly reduce the capacitance of the wire/foil?\n\n" " </div>\n\n" " <div class=\"tags t-capacitor t-capacitance\">\n" " <a href=\"/questions/tagged/capacitor\" class=\"post-tag\" title=\"show questions tagged 'capacitor'\" rel=\"tag\">capacitor</a> <a href=\"/questions/tagged/capacitance\" class=\"post-tag\" title=\"show questions tagged 'capacitance'\" rel=\"tag\">capacitance</a>\n\n" " </div>\n" " <div class=\"started fr\">\n\n\n" " <div class=\"user-info \">\n" " <div class=\"user-action-time\">\n\n\n" " asked <span title=\"2013-08-08 02:03:19Z\" class=\"relativetime\">Aug 8 at 2:03</span>\n" " </div>\n" " <div class=\"user-gravatar32\">\n" " <a href=\"/users/27085/j03m\"><div class=\"\"><img src=\"https://www.gravatar.com/avatar/a16354f806a5e7cdf68128173ec06ec6?s=32&d=identicon&r=PG\" alt=\"\" width=\"32\" height=\"32\"></div></a>\n" " </div>\n" " <div class=\"user-details\">\n" " <a href=\"/users/27085/j03m\">j03m</a><br>\n" " <span class=\"reputation-score\" title=\"reputation score\" dir=\"ltr\">146</span><span title=\"4 bronze badges\"><span class=\"badge3\"></span><span class=\"badgecount\">4</span></span>\n" " </div>\n" " </div>\n\n" " </div>\n" " </div>\n" "</div>\n\n" "<div class=\"question-summary\" id=\"question-summary-78322\">\n" " <div class=\"statscontainer\">\n" " <div class=\"statsarrow\"></div>\n" " <div class=\"stats\">\n" " <div class=\"vote\">\n" " <div class=\"votes\">\n" " <span class=\"vote-count-post \"><strong>-2</strong></span>\n" " <div class=\"viewcount\">votes</div>\n" " </div>\n" " </div>\n" " <div class=\"status answered-accepted\">\n" " <strong>1</strong>answer\n" " </div>\n" " </div>\n\n\n\n" "<div class=\"views \" title=\"63 views\">\n" " 63 views\n" "</div>\n" " </div>\n" " <div class=\"summary\">\n" " <h3><a href=\"/questions/78322/ground-wire-installation\" class=\"question-hyperlink\">Ground Wire Installation [closed]</a></h3>\n" " <div class=\"excerpt\">\n" " Currently I do not have ground in my house wiring. I am planing to install ground wiring but the floor around the main service panel is cemented and I don't think I can place a ground rod in the ...\n" " </div>\n\n" " <div class=\"tags t-wiring\">\n" " <a href=\"/questions/tagged/wiring\" class=\"post-tag\" title=\"show questions tagged 'wiring'\" rel=\"tag\">wiring</a>\n\n" " </div>\n" " <div class=\"started fr\">\n\n\n" " <div class=\"user-info \">\n" " <div class=\"user-action-time\">\n\n\n" " asked <span title=\"2013-08-08 00:38:13Z\" class=\"relativetime\">Aug 8 at 0:38</span>\n" " </div>\n" " <div class=\"user-gravatar32\">\n" " <a href=\"/users/27238/khiz\"><div class=\"\"><img src=\"https://www.gravatar.com/avatar/5a94e8f9238c314cab95243f99332222?s=32&d=identicon&r=PG\" alt=\"\" width=\"32\" height=\"32\"></div></a>\n" " </div>\n" " <div class=\"user-details\">\n" " <a href=\"/users/27238/khiz\">khiz</a><br>\n" " <span class=\"reputation-score\" title=\"reputation score\" dir=\"ltr\">33</span><span title=\"3 bronze badges\"><span class=\"badge3\"></span><span class=\"badgecount\">3</span></span>\n" " </div>\n" " </div>\n\n" " </div>\n" " </div>\n" "</div>\n\n" "<div class=\"question-summary\" id=\"question-summary-78319\">\n" " <div class=\"statscontainer\">\n" " <div class=\"statsarrow\"></div>\n" " <div class=\"stats\">\n" " <div class=\"vote\">\n" " <div class=\"votes\">\n" " <span class=\"vote-count-post \"><strong>1</strong></span>\n" " <div class=\"viewcount\">vote</div>\n" " </div>\n" " </div>\n" " <div class=\"status answered\">\n" " <strong>2</strong>answers\n" " </div>\n" " </div>\n\n\n\n" "<div class=\"views \" title=\"63 views\">\n" " 63 views\n" "</div>\n" " </div>\n" " <div class=\"summary\">\n" " <h3><a href=\"/questions/78319/performance-of-solar-panel-vs-dc-power-supply\" class=\"question-hyperlink\">Performance of solar panel vs. DC power supply</a></h3>\n" " <div class=\"excerpt\">\n" " I am building a solar swamp cooler for burning man (hot dry desert environment).\n\n" "Purchased a 15w solar panel that outputs 0.9a at 20V in full sun (verified as true with my voltmeter). The solar panel ...\n" " </div>\n\n" " <div class=\"tags t-power-supply t-dc t-solar-cell\">\n" " <a href=\"/questions/tagged/power-supply\" class=\"post-tag\" title=\"show questions tagged 'power-supply'\" rel=\"tag\">power-supply</a> <a href=\"/questions/tagged/dc\" class=\"post-tag\" title=\"show questions tagged 'dc'\" rel=\"tag\">dc</a> <a href=\"/questions/tagged/solar-cell\" class=\"post-tag\" title=\"show questions tagged 'solar-cell'\" rel=\"tag\">solar-cell</a>\n\n" " </div>\n" " <div class=\"started fr\">\n\n\n" " <div class=\"user-info \">\n" " <div class=\"user-action-time\">\n\n\n" " asked <span title=\"2013-08-08 00:07:34Z\" class=\"relativetime\">Aug 8 at 0:07</span>\n" " </div>\n" " <div class=\"user-gravatar32\">\n" " <a href=\"/users/27183/nimble\"><div class=\"\"><img src=\"https://www.gravatar.com/avatar/2bb088aedd0b5458b587e3bc104f1edc?s=32&d=identicon&r=PG\" alt=\"\" width=\"32\" height=\"32\"></div></a>\n" " </div>\n" " <div class=\"user-details\">\n" " <a href=\"/users/27183/nimble\">nimble</a><br>\n" " <span class=\"reputation-score\" title=\"reputation score\" dir=\"ltr\">11</span><span title=\"1 bronze badge\"><span class=\"badge3\"></span><span class=\"badgecount\">1</span></span>\n" " </div>\n" " </div>\n\n" " </div>\n" " </div>\n" "</div>\n\n" "<div class=\"question-summary\" id=\"question-summary-78318\">\n" " <div class=\"statscontainer\">\n" " <div class=\"statsarrow\"></div>\n" " <div class=\"stats\">\n" " <div class=\"vote\">\n" " <div class=\"votes\">\n" " <span class=\"vote-count-post \"><strong>0</strong></span>\n" " <div class=\"viewcount\">votes</div>\n" " </div>\n" " </div>\n" " <div class=\"status unanswered\">\n" " <strong>0</strong>answers\n" " </div>\n" " </div>\n\n\n\n" "<div class=\"views \" title=\"23 views\">\n" " 23 views\n" "</div>\n" " </div>\n" " <div class=\"summary\">\n" " <h3><a href=\"/questions/78318/altium-simulation-node-voltages\" class=\"question-hyperlink\">Altium Simulation Node Voltages</a></h3>\n" " <div class=\"excerpt\">\n" " When simulating a circuit in Altium it generates signals based on the components and net labels placed in the circuit, eg:\n\n" "<span class='tex2jax_ignore'>r1[i]\n" "r1[p]\n" "v1\n" "v2\n" "</span>\n\n" "Altium also adds the ...\n" " </div>\n\n" " <div class=\"tags t-simulation t-circuit-analysis t-altium\">\n" " <a href=\"/questions/tagged/simulation\" class=\"post-tag\" title=\"show questions tagged 'simulation'\" rel=\"tag\">simulation</a> <a href=\"/questions/tagged/circuit-analysis\" class=\"post-tag\" title=\"show questions tagged 'circuit-analysis'\" rel=\"tag\">circuit-analysis</a> <a href=\"/questions/tagged/altium\" class=\"post-tag\" title=\"show questions tagged 'altium'\" rel=\"tag\">altium</a>\n\n" " </div>\n" " <div class=\"started fr\">\n\n\n" " <div class=\"user-info \">\n" " <div class=\"user-action-time\">\n\n\n" " asked <span title=\"2013-08-07 23:55:41Z\" class=\"relativetime\">Aug 7 at 23:55</span>\n" " </div>\n" " <div class=\"user-gravatar32\">\n" " <a href=\"/users/27237/troy\"><div class=\"\"><img src=\"https://www.gravatar.com/avatar/5c9a9c526c1c796a536814e3b04405d1?s=32&d=identicon&r=PG\" alt=\"\" width=\"32\" height=\"32\"></div></a>\n" " </div>\n" " <div class=\"user-details\">\n" " <a href=\"/users/27237/troy\">Troy</a><br>\n" " <span class=\"reputation-score\" title=\"reputation score\" dir=\"ltr\">1</span><span title=\"1 bronze badge\"><span class=\"badge3\"></span><span class=\"badgecount\">1</span></span>\n" " </div>\n" " </div>\n\n" " </div>\n" " </div>\n" "</div>\n\n" "<div class=\"question-summary\" id=\"question-summary-78315\">\n" " <div class=\"statscontainer\">\n" " <div class=\"statsarrow\"></div>\n" " <div class=\"stats\">\n" " <div class=\"vote\">\n" " <div class=\"votes\">\n" " <span class=\"vote-count-post \"><strong>1</strong></span>\n" " <div class=\"viewcount\">vote</div>\n" " </div>\n" " </div>\n" " <div class=\"status answered-accepted\">\n" " <strong>2</strong>answers\n" " </div>\n" " </div>\n\n\n\n" "<div class=\"views \" title=\"146 views\">\n" " 146 views\n" "</div>\n" " </div>\n" " <div class=\"summary\">\n" " <h3><a href=\"/questions/78315/why-does-the-voltage-changes-in-this-simple-circuit\" class=\"question-hyperlink\">Why does the voltage changes in this simple circuit?</a></h3>\n" " <div class=\"excerpt\">\n" " I'm beginning to learn electronics, and there's something I just can't grasp. I was told that a high resistance in a circuit would lead to a smaller current passing through it, but the voltage would ...\n" " </div>\n\n" " <div class=\"tags t-power t-voltage t-current t-resistance t-ohms-law\">\n" " <a href=\"/questions/tagged/power\" class=\"post-tag\" title=\"show questions tagged 'power'\" rel=\"tag\">power</a> <a href=\"/questions/tagged/voltage\" class=\"post-tag\" title=\"show questions tagged 'voltage'\" rel=\"tag\">voltage</a> <a href=\"/questions/tagged/current\" class=\"post-tag\" title=\"show questions tagged 'current'\" rel=\"tag\">current</a> <a href=\"/questions/tagged/resistance\" class=\"post-tag\" title=\"show questions tagged 'resistance'\" rel=\"tag\">resistance</a> <a href=\"/questions/tagged/ohms-law\" class=\"post-tag\" title=\"show questions tagged 'ohms-law'\" rel=\"tag\">ohms-law</a>\n\n" " </div>\n" " <div class=\"started fr\">\n\n\n" " <div class=\"user-info \">\n" " <div class=\"user-action-time\">\n\n\n" " asked <span title=\"2013-08-07 23:08:48Z\" class=\"relativetime\">Aug 7 at 23:08</span>\n" " </div>\n" " <div class=\"user-gravatar32\">\n" " <a href=\"/users/27236/wingleader\"><div class=\"\"><img src=\"https://www.gravatar.com/avatar/01d2f745e0e93e81d23ca4214668eadb?s=32&d=identicon&r=PG\" alt=\"\" width=\"32\" height=\"32\"></div></a>\n" " </div>\n" " <div class=\"user-details\">\n" " <a href=\"/users/27236/wingleader\">wingleader</a><br>\n" " <span class=\"reputation-score\" title=\"reputation score\" dir=\"ltr\">8</span><span title=\"2 bronze badges\"><span class=\"badge3\"></span><span class=\"badgecount\">2</span></span>\n" " </div>\n" " </div>\n\n" " </div>\n" " </div>\n" "</div>\n\n" "<div class=\"question-summary\" id=\"question-summary-78307\">\n" " <div class=\"statscontainer\">\n" " <div class=\"statsarrow\"></div>\n" " <div class=\"stats\">\n" " <div class=\"vote\">\n" " <div class=\"votes\">\n" " <span class=\"vote-count-post \"><strong>-1</strong></span>\n" " <div class=\"viewcount\">votes</div>\n" " </div>\n" " </div>\n" " <div class=\"status answered-accepted\">\n" " <strong>4</strong>answers\n" " </div>\n" " </div>\n\n\n\n" "<div class=\"views \" title=\"89 views\">\n" " 89 views\n" "</div>\n" " </div>\n" " <div class=\"summary\">\n" " <h3><a href=\"/questions/78307/how-do-i-figure-out-the-correct-polarity-of-a-dc-barrel-connector\" class=\"question-hyperlink\">How do I figure out the correct polarity of a DC barrel connector</a></h3>\n" " <div class=\"excerpt\">\n" " I'm in the U.S. and I bought a digital wall clock from the U.K. which came with an AC adapter with input 230V/50Hz/90mA and output 9V/800mA. Now I could get a transformer to convert 120V to 230V but ...\n" " </div>\n\n" " <div class=\"tags t-multimeter t-polarity\">\n" " <a href=\"/questions/tagged/multimeter\" class=\"post-tag\" title=\"show questions tagged 'multimeter'\" rel=\"tag\">multimeter</a> <a href=\"/questions/tagged/polarity\" class=\"post-tag\" title=\"show questions tagged 'polarity'\" rel=\"tag\">polarity</a>\n\n" " </div>\n" " <div class=\"started fr\">\n\n\n" " <div class=\"user-info \">\n" " <div class=\"user-action-time\">\n\n\n" " asked <span title=\"2013-08-07 21:38:15Z\" class=\"relativetime\">Aug 7 at 21:38</span>\n" " </div>\n" " <div class=\"user-gravatar32\">\n" " <a href=\"/users/27233/eydelber\"><div class=\"\"><img src=\"https://www.gravatar.com/avatar/f882365e2a203587fe941634b3a376b2?s=32&d=identicon&r=PG\" alt=\"\" width=\"32\" height=\"32\"></div></a>\n" " </div>\n" " <div class=\"user-details\">\n" " <a href=\"/users/27233/eydelber\">eydelber</a><br>\n" " <span class=\"reputation-score\" title=\"reputation score\" dir=\"ltr\">101</span><span title=\"4 bronze badges\"><span class=\"badge3\"></span><span class=\"badgecount\">4</span></span>\n" " </div>\n" " </div>\n\n" " </div>\n" " </div>\n" "</div>\n" " </div>\n\n" " <br class=\"cbt\">\n\n\n" " <div class=\"page-sizer fr\">\n" " <a href=\"/questions?pagesize=15&amp;sort=newest\" title=\"show 15 items per page\" class=\"page-numbers current\">15</a>\n" " <a href=\"/questions?pagesize=30&amp;sort=newest\" title=\"show 30 items per page\" class=\"page-numbers \">30</a>\n" " <a href=\"/questions?pagesize=50&amp;sort=newest\" title=\"show 50 items per page\" class=\"page-numbers \">50</a>\n" " <span class=\"page-numbers desc\">per page</span>\n" " </div>\n" "<div class=\"pager fl\" >\n" "<a href=\"/questions?page=43&amp;sort=newest\" title=\"go to page 43\" rel=\"prev\"><span class=\"page-numbers prev\">prev </span></a>\n" "<a href=\"/questions?page=1&amp;sort=newest\" title=\"go to page 1\"><span 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class=\"module\" id=\"questions-count\">\n" " <div class=\"summarycount al\">20,098</div>\n" " <p>questions</p>\n" " </div>\n\n\n\n\n\n\n\n" " <div class=\"module\" id=\"related-tags\">\n" " <h4 id=\"h-related-tags\">Related Tags</h4>\n\n" " <a href=\"/questions/tagged/arduino\" class=\"post-tag\" title=\"show questions tagged 'arduino'\" rel=\"tag\">arduino</a>&nbsp;<span class=\"item-multiplier\"><span class=\"item-multiplier-x\">&times;</span>&nbsp;<span class=\"item-multiplier-count\">2030</span></span><br>\n" " <a href=\"/questions/tagged/microcontroller\" class=\"post-tag\" title=\"show questions tagged 'microcontroller'\" rel=\"tag\">microcontroller</a>&nbsp;<span class=\"item-multiplier\"><span class=\"item-multiplier-x\">&times;</span>&nbsp;<span class=\"item-multiplier-count\">1432</span></span><br>\n" " <a href=\"/questions/tagged/power-supply\" class=\"post-tag\" title=\"show questions tagged 'power-supply'\" rel=\"tag\">power-supply</a>&nbsp;<span 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travelers\">Travel</a></li>\n" " <li><a href=\"http://christianity.stackexchange.com\" title=\"committed Christians, experts in Christianity and those interested in learning more\">Christianity</a></li>\n" " <li><a href=\"http://gaming.stackexchange.com\" title=\"passionate videogamers on all platforms\">Arqade (gaming)</a></li>\n" " <li><a href=\"http://bicycles.stackexchange.com\" title=\"people who build and repair bicycles, people who train cycling, or commute on bicycles\">Bicycles</a></li>\n" " <li><a href=\"http://rpg.stackexchange.com\" title=\"gamemasters and players of tabletop, paper-and-pencil role-playing games\">Role-playing Games</a></li>\n\n" " <li>\n" " <a href=\"http://stackexchange.com/sites#culturerecreation\" class=\"more\">\n" " more (21)\n" " </a>\n" " </li>\n" " </ol>\n" " </td>\n" " <td>\n" " <ol>\n" " <li><a href=\"http://math.stackexchange.com\" title=\"people studying math at any level and professionals in related fields\">Mathematics</a></li>\n" " <li><a href=\"http://stats.stackexchange.com\" title=\"statisticians, data analysts, data miners and data visualization experts\">Cross Validated (stats)</a></li>\n" " <li><a href=\"http://cstheory.stackexchange.com\" title=\"theoretical computer scientists and researchers in related fields\">Theoretical Computer Science</a></li>\n" " <li><a href=\"http://physics.stackexchange.com\" title=\"active researchers, academics and students of physics\">Physics</a></li>\n" " <li><a href=\"http://mathoverflow.net\" title=\"professional mathematicians\">MathOverflow</a></li>\n\n" " <li>\n" " <a href=\"http://stackexchange.com/sites#science\" class=\"more\">\n" " more (7)\n" " </a>\n" " </li>\n" " </ol>\n" " </td>\n" " <td>\n" " <ol>\n" " <li><a href=\"http://stackapps.com\" title=\"apps, scripts, and development with the Stack Exchange API\">Stack Apps</a></li>\n" " <li><a href=\"http://meta.stackoverflow.com\" title=\"meta-discussion of the Stack Exchange family of Q&amp;A websites\">Meta Stack Overflow</a></li>\n" " <li><a href=\"http://area51.stackexchange.com\" title=\"proposing new sites in the Stack Exchange network\">Area 51</a></li>\n" " <li><a href=\"http://careers.stackoverflow.com\">Stack Overflow Careers</a></li>\n\n" " </ol>\n" " </td>\n" " </tr>\n" "</table>\n" " </div>\n" " </div>\n\n" " <div id=\"copyright\">\n" " site design / logo &copy; 2013 stack exchange inc;\n" " user contributions licensed under <a href=\"http://creativecommons.org/licenses/by-sa/3.0/\" rel=\"license\">cc-wiki</a>\n" " with <a href=\"http://blog.stackoverflow.com/2009/06/attribution-required/\" rel=\"license\">attribution required</a>\n" " </div>\n" " <div id=\"footer-flair\">\n" " <a href=\"http://creativecommons.org/licenses/by-sa/3.0/\" class=\"cc-wiki-link\"></a>\n" " </div>\n" " <div id=\"svnrev\">\n" " rev 2013.8.28.977\n" " </div>\n\n" " </div>\n" " </div>\n" " <noscript>\n" " <div id=\"noscript-warning\">Electrical Engineering Stack Exchange works best with JavaScript enabled<img src=\"http://pixel.quantserve.com/pixel/p-c1rF4kxgLUzNc.gif\" alt=\"\" class=\"dno\"></div>\n" " </noscript>\n\n" " <script type=\"text/javascript\">var _gaq=_gaq||[];_gaq.push(['_setAccount','UA-5620270-24']);\n" " _gaq.push(['_setDomainName','.stackexchange.com']);\n" "_gaq.push(['_trackPageview']);\n" " var _qevents = _qevents || [];\n" " (function () {\n" " var ssl='https:'==document.location.protocol,\n" " s=document.getElementsByTagName('script')[0],\n" " ga=document.createElement('script');\n" " ga.type='text/javascript';\n" " ga.async=true;\n" " ga.src=(ssl?'https://ssl':'http://www')+'.google-analytics.com/ga.js';\n" " s.parentNode.insertBefore(ga,s);\n" " var sc=document.createElement('script');\n" " sc.type='text/javascript';\n" " sc.async=true;\n" " sc.src=(ssl?'https://secure':'http://edge')+'.quantserve.com/quant.js';\n" " s.parentNode.insertBefore(sc,s);\n" " })();\n" " _qevents.push({ qacct: \"p-c1rF4kxgLUzNc\" });\n" " </script>\n\n" "</body>\n" "</html>") matches = re.finditer(regex, test_str) 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