http://code.activestate.com/recipes/tags/meta:loc=12/views/2017-07-11T18:57:54-07:00ActiveState Code Recipes2001-05-29T09:51:54-07:00andy mckayhttp://code.activestate.com/recipes/users/92886/http://code.activestate.com/recipes/59866-getting-a-value-from-a-dictionary/

<p style="color: grey"> Python recipe 59866 by <a href="/recipes/users/92886/">andy mckay</a> (<a href="/recipes/tags/shortcuts/">shortcuts</a>). </p> <p>Want to get a value from a dictionary but want to make sure that the value exists in the dictionary? Then use the incredibly useful get method.</p>

2017-07-11T18:57:54-07:00Jorj X. McKiehttp://code.activestate.com/recipes/users/4193772/http://code.activestate.com/recipes/580796-how-to-handle-pdf-embedded-files-with-pymupdf/

<p style="color: grey"> Python recipe 580796 by <a href="/recipes/users/4193772/">Jorj X. McKie</a> (<a href="/recipes/tags/embedded_files/">embedded_files</a>, <a href="/recipes/tags/fitz/">fitz</a>, <a href="/recipes/tags/mupdf/">mupdf</a>, <a href="/recipes/tags/pdf/">pdf</a>, <a href="/recipes/tags/pymupdf/">pymupdf</a>). Revision 3. </p> <p>Version 1.11.0 (based on MuPDF v1.11) allows exporting, importing and interrogating files embedded in a PDF.</p> <p>PDF "/EmbeddedFiles" are similar to ZIP archives (or the Microsoft OLE technique), allowing arbitrary data to be incorporated in a PDF and benefit from its unique features.</p>

2001-03-12T06:36:58-08:00Jeff Bauerhttp://code.activestate.com/recipes/users/98055/http://code.activestate.com/recipes/52220-the-simplest-cgi-program/

<p style="color: grey"> Python recipe 52220 by <a href="/recipes/users/98055/">Jeff Bauer</a> (<a href="/recipes/tags/cgi/">cgi</a>). </p> <p>The simplest CGI program. This script displays the current version of Python and the environment values.</p>

2004-03-08T00:21:23-08:00Sean Rosshttp://code.activestate.com/recipes/users/761068/http://code.activestate.com/recipes/273085-sample-with-replacement/

<p style="color: grey"> Python recipe 273085 by <a href="/recipes/users/761068/">Sean Ross</a> (<a href="/recipes/tags/algorithms/">algorithms</a>). Revision 3. </p> <p>For taking k random samples (with replacement) from a population, where k may be greater than len(population).</p>

2001-06-14T19:42:23-07:00Paul Prescodhttp://code.activestate.com/recipes/users/11203/http://code.activestate.com/recipes/65128-extract-text-from-xml-document/

<p style="color: grey"> Python recipe 65128 by <a href="/recipes/users/11203/">Paul Prescod</a> (<a href="/recipes/tags/xml/">xml</a>). Revision 2. </p> <p>People often ask how to extract the text from an XML document. This small program does it.</p>

2004-10-08T06:21:21-07:00mark andrewhttp://code.activestate.com/recipes/users/2085251/http://code.activestate.com/recipes/307618-class-with-default-method-handler/

<p style="color: grey"> Python recipe 307618 by <a href="/recipes/users/2085251/">mark andrew</a> (<a href="/recipes/tags/oop/">oop</a>). </p> <p>A class whose objects can handle undefined method calls, passing them on to a default handler.</p>

2014-09-20T19:33:41-07:00juanhttp://code.activestate.com/recipes/users/4190606/http://code.activestate.com/recipes/578923-first-n-primes-numbers/

<p style="color: grey"> Python recipe 578923 by <a href="/recipes/users/4190606/">juan</a> . Revision 6. </p> <p>Using the Sieve of Eratosthenes find the first n primes numbers.</p>

2014-11-07T17:51:32-08:00Stephen Chappellhttp://code.activestate.com/recipes/users/2608421/http://code.activestate.com/recipes/578959-draw-a-diamond-with-asterisks-using-recursion/

<p style="color: grey"> Python recipe 578959 by <a href="/recipes/users/2608421/">Stephen Chappell</a> (<a href="/recipes/tags/drawing/">drawing</a>). </p> <p>Given the following function header:</p> <pre class="prettyprint"><code>def triangles(n): </code></pre> <p>If n for example is 5, then the drawing would be like this:</p> <pre class="prettyprint"><code> * * * * * * * * * * * * * </code></pre>

2012-09-09T08:08:46-07:00Ahmed Kamelhttp://code.activestate.com/recipes/users/4183490/http://code.activestate.com/recipes/578254-running-linux-command-inside-your-python-script/

<p style="color: grey"> Python recipe 578254 by <a href="/recipes/users/4183490/">Ahmed Kamel</a> (<a href="/recipes/tags/linux/">linux</a>, <a href="/recipes/tags/python/">python</a>, <a href="/recipes/tags/sysadmin/">sysadmin</a>). </p> <p>Running any linux command line inside your python script.</p>

2003-11-28T03:09:30-08:00Richard Philipshttp://code.activestate.com/recipes/users/98125/http://code.activestate.com/recipes/252176-dicts-from-lists/

<p style="color: grey"> Python recipe 252176 by <a href="/recipes/users/98125/">Richard Philips</a> (<a href="/recipes/tags/algorithms/">algorithms</a>). </p> <p>Simple oneliner to built a dictionary from a list</p>

2004-08-05T10:25:59-07:00Yaroslav Bulatovhttp://code.activestate.com/recipes/users/1915780/http://code.activestate.com/recipes/298339-more-accurate-sum/

<p style="color: grey"> Python recipe 298339 by <a href="/recipes/users/1915780/">Yaroslav Bulatov</a> (<a href="/recipes/tags/algorithms/">algorithms</a>). Revision 3. </p> <p>Built-in "sum" function, as well as add.reduce functions in Numeric/numarray introduce a large error when summing large arrays of like elements. I got relative error of about 1e-9 after summing 10 million doubles between 0 and 1. Function below has error less than 1e-15, doesn't use any additional memory (although it destroys the data array), and also runs asymptotically faster for unlimited precision numbers.</p>

2003-03-28T20:27:26-08:00Jason Whitlarkhttp://code.activestate.com/recipes/users/302240/http://code.activestate.com/recipes/192401-quickly-remove-or-order-columns-in-a-list-of-lists/

<p style="color: grey"> Python recipe 192401 by <a href="/recipes/users/302240/">Jason Whitlark</a> . </p> <p>I've often needed to take out or reorder the columns in a list of lists. I'm embarrased to say it took me a while to think of this, it's so simple, but I looked around and have not found any examples of it, so...</p>

2004-06-13T23:03:49-07:00Bill Bellhttp://code.activestate.com/recipes/users/98151/http://code.activestate.com/recipes/269345-how-to-connect-to-an-already-running-instance-of-i/

<p style="color: grey"> Python recipe 269345 by <a href="/recipes/users/98151/">Bill Bell</a> (<a href="/recipes/tags/web/">web</a>). Revision 2. </p> <p>Various sources (but principally Hammond and Robinson) show how to instantiate Internet Explorer in order to have access to its interfaces. However, few places show how to connect to an instance that is already running, which is so easy in VB.</p> <p>Thanks are due to someone called "gcash" for this idea. See <a href="http://dbforums.com/t867088.html." rel="nofollow">http://dbforums.com/t867088.html.</a></p> <p>It just seemed to me that this is a good recipe to have in this collection as a reference to a certain approach, rather than as a full solution.</p>

2009-02-20T22:35:07-08:00Trent Mickhttp://code.activestate.com/recipes/users/4173505/http://code.activestate.com/recipes/576656-quick-python-profiling-with-hotshot/

<p style="color: grey"> Python recipe 576656 by <a href="/recipes/users/4173505/">Trent Mick</a> (<a href="/recipes/tags/hotshot/">hotshot</a>, <a href="/recipes/tags/performance/">performance</a>, <a href="/recipes/tags/profile/">profile</a>). Revision 2. </p> <p>This is a quick snippet that I use occasionally to profile some pure-Python code, using <a href="http://docs.python.org/library/hotshot.html#module-hotshot"><code>hotshot</code></a>. Basically it is this:</p> <ol> <li>Put this <code>@hotshotit</code> decorator on the function you want to profile.</li> <li>Run your code through some representative paces. The result will be a <code>&lt;functionname&gt;.prof</code> in the current directory.</li> <li>Process the <code>.prof</code> file and print the top 20 hotspots with the given "show_stats.py" script.</li> </ol> <p>Props to <a href="http://blogs.activestate.com/toddw/">Todd</a> for slapping this code together.</p> <p>Hotshot <a href="http://docs.python.org/library/profile.html">is a little out of favour</a> now, so I should -- or Todd :) -- should really come up with an equivalent that uses <code>cProfile</code>.</p>

2009-04-26T18:10:55-07:00Sridhar Ratnakumarhttp://code.activestate.com/recipes/users/4169511/http://code.activestate.com/recipes/576720-lazy-property/

<p style="color: grey"> Python recipe 576720 by <a href="/recipes/users/4169511/">Sridhar Ratnakumar</a> (<a href="/recipes/tags/evaluation/">evaluation</a>, <a href="/recipes/tags/lazy/">lazy</a>, <a href="/recipes/tags/lazy_evaluation/">lazy_evaluation</a>). Revision 6. </p> <p>Python does not have lazy evaluation syntax features built-in, but fortunately decorators can be used with new-style classes to emulate such a feature. There are cases where one wants <code>foo.property</code> to return the actual property whose calculation takes significant amount of time.</p> <p>This recipe adapts the existing <code>property</code> to provide a <code>lazypropery</code> decorator that does this.</p> <p>See the first comment below for an example usage.</p> <p>Also see: <a href="http://en.wikipedia.org/wiki/Lazy_initialization">lazy initialization</a></p>

2010-03-27T00:58:24-07:00FB36http://code.activestate.com/recipes/users/4172570/http://code.activestate.com/recipes/577154-calculating-pi-using-random-numbers-monte-carlo-me/

<p style="color: grey"> Python recipe 577154 by <a href="/recipes/users/4172570/">FB36</a> (<a href="/recipes/tags/math/">math</a>, <a href="/recipes/tags/pi/">pi</a>, <a href="/recipes/tags/random/">random</a>). </p> <p>Calculating PI using random numbers (Monte Carlo method)</p>

2005-05-08T10:42:59-07:00Zoran Isailovskihttp://code.activestate.com/recipes/users/2400454/http://code.activestate.com/recipes/413487-quick-test-if-strings-are-identifiers/

<p style="color: grey"> Python recipe 413487 by <a href="/recipes/users/2400454/">Zoran Isailovski</a> (<a href="/recipes/tags/programs/">programs</a>). Revision 3. </p> <p>Sometimes you need strings to be true identifiers, for ex. to represent symbolic names. Smalltalk offers the type 'Symbol' for this purpose. In python, you need to test this explicitly. Here is a quick way.</p>

2008-08-18T09:26:07-07:00nosklohttp://code.activestate.com/recipes/users/4166478/http://code.activestate.com/recipes/576428-user-list-subclass/

<p style="color: grey"> Python recipe 576428 by <a href="/recipes/users/4166478/">nosklo</a> (<a href="/recipes/tags/list/">list</a>, <a href="/recipes/tags/slices/">slices</a>, <a href="/recipes/tags/subclass/">subclass</a>, <a href="/recipes/tags/__getitem__/">__getitem__</a>). Revision 2. </p> <p>As subclassing list has a problem when using __getitem__, __delitem__ and __setitem__ methods with slices (they don't get called because parent implements __getslice__, __delslice__ and __setslice__ respectively), I've coded this UserList class that is a subclass of list, but overwrites these methods. By subclassing this class, you can overwrite __getitem__ and it will be called correctly for slices.</p>

2009-09-28T16:19:23-07:00Trent Mickhttp://code.activestate.com/recipes/users/4173505/http://code.activestate.com/recipes/576915-touch/

<p style="color: grey"> Python recipe 576915 by <a href="/recipes/users/4173505/">Trent Mick</a> (<a href="/recipes/tags/file/">file</a>, <a href="/recipes/tags/shell/">shell</a>, <a href="/recipes/tags/touch/">touch</a>, <a href="/recipes/tags/unix/">unix</a>). </p> <p>Python function a la the Unix <code>touch</code> program (<a href="http://www.manpagez.com/man/1/touch/">man touch</a>).</p>

2006-09-01T08:06:29-07:00Ori Peleghttp://code.activestate.com/recipes/users/2056315/http://code.activestate.com/recipes/497009-safely-defining-__setattr__/

<p style="color: grey"> Python recipe 497009 by <a href="/recipes/users/2056315/">Ori Peleg</a> (<a href="/recipes/tags/shortcuts/">shortcuts</a>). Revision 2. </p> <p>Overriding __setattr__ in classes requires care when setting attributes yourself. Here's an idea for safely setting attributes in __init__.</p> <p>Update: this idea doesn't work. See Mike Foord's recipe for one that does:</p> <p><a href="http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/389916" rel="nofollow">http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/389916</a></p>