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<p class="MsoNormal">And if you want to know how it works, I suggest SCIP. https://scip.zib.de/<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal"><b><span style="font-size:12.0pt;color:black">From: </span></b><span style="font-size:12.0pt;color:black">Friam <friam-bounces@redfish.com> on behalf of Pieter Steenekamp <pieters@randcontrols.co.za><br>
<b>Reply-To: </b>The Friday Morning Applied Complexity Coffee Group <friam@redfish.com><br>
<b>Date: </b>Friday, September 20, 2019 at 12:52 PM<br>
<b>To: </b>The Friday Morning Applied Complexity Coffee Group <friam@redfish.com><br>
<b>Subject: </b>Re: [FRIAM] Optimization problem<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Two possible approaches are: <o:p></o:p></p>
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<p class="MsoNormal">a) Solve the problem yourself. Use one or a combination of standard algorithms ( eg you mentioned linear programming and greedy algorithms, there are many more of course) and/or your own custom algorithm. If you wish to go this route and
want to learn about the subject, I recommend the series of MOOCS by Stanford's Tim Roughgarden <a href="https://www.coursera.org/specializations/algorithms">https://www.coursera.org/specializations/algorithms</a><o:p></o:p></p>
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<p class="MsoNormal">Or, I think yours is probably a knapsack -type problem and the MOOC <a href="https://www.coursera.org/learn/discrete-optimization">https://www.coursera.org/learn/discrete-optimization</a> covers that relatively well.<o:p></o:p></p>
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<p class="MsoNormal">b) But if you just want to get the solution you can use optimization software like <a href="https://www.ibm.com/za-en/products/ilog-cplex-optimization-studio">https://www.ibm.com/za-en/products/ilog-cplex-optimization-studio</a> (they have
a free edition that will be good enough for your application) will solve it for you without you necessarily knowing how the software does it. <o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">On Fri, 20 Sep 2019 at 21:00, Gary Schiltz <<a href="mailto:gary@naturesvisualarts.com">gary@naturesvisualarts.com</a>> wrote:<o:p></o:p></p>
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<p class="MsoNormal">I'd like advice on possible ways to solve the following problem<br>
(plumbers must surely face this all the time). I need to cut a set of<br>
metal tubes of varying lengths from standard length (6 meter)<br>
galvanized conduit stock. The goal is to find the number of tubes I<br>
need to buy, and the order of cuts to produce the minimum amount of<br>
leftover, unused tube. I'm interested in what types of solutions<br>
people use for similar 1-dimensional problems, e.g. linear<br>
programming, greedy algorithms, etc. (I've been Googling). I'm only<br>
looking to cut around 15-25 pieces, so my gut feeling is that an<br>
exhaustive search of all possible solutions, though probably NP-hard,<br>
would be feasible to perform. Working programs, as well as libraries<br>
in any language would be a bonus.<br>
<br>
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