http://code.activestate.com/recipes/tags/optimization-dijkstra/2016-10-29T20:22:27-07:00ActiveState Code Recipes2016-10-29T20:22:27-07:00Harald Liederhttp://code.activestate.com/recipes/users/4191581/http://code.activestate.com/recipes/580711-pdf-wrapper-for-fileoptimizer/

<p style="color: grey"> Python recipe 580711 by <a href="/recipes/users/4191581/">Harald Lieder</a> (<a href="/recipes/tags/fileoptimizer/">fileoptimizer</a>, <a href="/recipes/tags/fitz/">fitz</a>, <a href="/recipes/tags/mupdf/">mupdf</a>, <a href="/recipes/tags/optimization/">optimization</a>, <a href="/recipes/tags/pdf/">pdf</a>, <a href="/recipes/tags/pymupdf/">pymupdf</a>). </p> <p>Among dozens of other filetypes, FileOptimizer also compresses PDFs - often significantly. The issue is that the used plugin <em>smpdf</em> is free for non-commercial use only and it annoyingly <strong>also overwrites metadata</strong> information to state this.</p> <p>The following tool remedies these metadata changes (but not the license situation!).</p>

2016-08-07T22:02:10-07:00Raymond Hettingerhttp://code.activestate.com/recipes/users/178123/http://code.activestate.com/recipes/580610-auto-differentiation/

<p style="color: grey"> Python recipe 580610 by <a href="/recipes/users/178123/">Raymond Hettinger</a> (<a href="/recipes/tags/autodifferentiation/">autodifferentiation</a>, <a href="/recipes/tags/calculus/">calculus</a>, <a href="/recipes/tags/descent/">descent</a>, <a href="/recipes/tags/gradient/">gradient</a>, <a href="/recipes/tags/math/">math</a>, <a href="/recipes/tags/optimization/">optimization</a>, <a href="/recipes/tags/vector/">vector</a>). Revision 5. </p> <p>Directly computes derivatives from ordinary Python functions using auto differentiation. The technique directly computes the desired derivatives to full precision without resorting to symbolic math and without making estimates bases on numerical methods.</p> <p>The module provides a Num class for "dual" numbers that performs both regular floating point math on a value and its derivative at the same time. In addition, the module provides drop-in substitutes for most of the functions in the math module. There are also tools for partial derivatives, directional derivatives, gradients of scalar fields, and the curl and divergence of vector fields.</p>

2013-04-05T12:49:36-07:00Sander Evershttp://code.activestate.com/recipes/users/4173111/http://code.activestate.com/recipes/578508-finding-sets-in-the-card-game-set/

<p style="color: grey"> Python recipe 578508 by <a href="/recipes/users/4173111/">Sander Evers</a> (<a href="/recipes/tags/algorithm/">algorithm</a>, <a href="/recipes/tags/optimization/">optimization</a>, <a href="/recipes/tags/search/">search</a>, <a href="/recipes/tags/setgame/">setgame</a>). Revision 2. </p> <p>In the card game <a href="http://en.wikipedia.org/wiki/Set_%28game%29">SET!</a>, players are shown an array of 12 (or more) symbol cards and try to identify a so-called 3-card <strong>set</strong> among these cards as quickly as possible.</p> <p>A card has four attributes (number, shape, color and shading), each of which can take 3 possible values. In a <strong>set</strong>, for each attribute, all three cards should have either the same value, or the three different values.</p> <p>This recipe solves the problem of finding <em>all</em> sets within an array of an arbitrary number of cards, showing some clever optimizations and celebrating the clarity of Python in expressing the algorithms.</p>

2011-08-10T23:54:12-07:00Raymond Hettingerhttp://code.activestate.com/recipes/users/178123/http://code.activestate.com/recipes/577834-compare-speeds-of-different-kinds-of-access-to-var/

<p style="color: grey"> Python recipe 577834 by <a href="/recipes/users/178123/">Raymond Hettinger</a> (<a href="/recipes/tags/optimization/">optimization</a>). Revision 5. </p> <p>Compare speeds of locals, nested scopes, global, builtins, instance variables, and class variables.</p>

2011-07-02T15:14:33-07:00Kaushik Ghosehttp://code.activestate.com/recipes/users/4166965/http://code.activestate.com/recipes/577776-speeding-up-computations-using-a-lookup-table-part/

<p style="color: grey"> Python recipe 577776 by <a href="/recipes/users/4166965/">Kaushik Ghose</a> (<a href="/recipes/tags/math/">math</a>, <a href="/recipes/tags/matplotlib/">matplotlib</a>, <a href="/recipes/tags/optimization/">optimization</a>). </p> <p>I needed to use the cumulative normal distribution and normal probability density functions repeatedly for some data analysis. I found that I could speed things up drastically by using a lookup table and matplotlib's builtin interpolation function.</p>

2011-03-01T03:46:26-08:00Sunjay Varmahttp://code.activestate.com/recipes/users/4174115/http://code.activestate.com/recipes/577255-flatten-a-list-or-list-of-lists-etc/

<p style="color: grey"> Python recipe 577255 by <a href="/recipes/users/4174115/">Sunjay Varma</a> (<a href="/recipes/tags/extend/">extend</a>, <a href="/recipes/tags/flatten/">flatten</a>, <a href="/recipes/tags/list/">list</a>, <a href="/recipes/tags/optimization/">optimization</a>, <a href="/recipes/tags/python/">python</a>, <a href="/recipes/tags/smart/">smart</a>). Revision 2. </p> <p>I created this function sometime ago for my own purposes. It simply flattens a list.</p> <p>Check out the first comment for another version of someone else's design.</p>

2009-09-15T00:34:37-07:00Gabriel Genellinahttp://code.activestate.com/recipes/users/924636/http://code.activestate.com/recipes/576904-decorator-for-bindingconstants-at-compile-time/

<p style="color: grey"> Python recipe 576904 by <a href="/recipes/users/924636/">Gabriel Genellina</a> (<a href="/recipes/tags/optimisation/">optimisation</a>, <a href="/recipes/tags/optimization/">optimization</a>, <a href="/recipes/tags/programs/">programs</a>). </p> <p>Decorator for automatic code optimization. If a global is known at compile time, replace it with a constant. Fold tuples of constants into a single constant. Fold constant attribute lookups into a single constant.</p> <p>This is only an update of <a href="http://code.activestate.com/recipes/277940/">Recipe 277940</a>, making it compatible with Python 3. All credit must go to the original author, Raymond Hettinger.</p>

2009-04-20T06:31:13-07:00Agnius Vasiliauskashttp://code.activestate.com/recipes/users/4169134/http://code.activestate.com/recipes/576645-evolution-optimization-strategy/

<p style="color: grey"> Python recipe 576645 by <a href="/recipes/users/4169134/">Agnius Vasiliauskas</a> (<a href="/recipes/tags/ai/">ai</a>, <a href="/recipes/tags/evolution/">evolution</a>, <a href="/recipes/tags/evolution_strategy/">evolution_strategy</a>, <a href="/recipes/tags/gene/">gene</a>, <a href="/recipes/tags/genetic_algorithm/">genetic_algorithm</a>, <a href="/recipes/tags/np_complete/">np_complete</a>, <a href="/recipes/tags/optimization/">optimization</a>). Revision 6. </p> <p>Algorithm for solving search and optimization problems.</p>