You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
MIPLearn/0.4/guide/solvers/index.html

641 lines
32 KiB

<!DOCTYPE html>
<html lang="en" data-content_root="../../" >
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" /><meta name="viewport" content="width=device-width, initial-scale=1" />
<title>9. Learning Solver &#8212; MIPLearn 0.4</title>
<script data-cfasync="false">
document.documentElement.dataset.mode = localStorage.getItem("mode") || "";
document.documentElement.dataset.theme = localStorage.getItem("theme") || "";
</script>
<!-- Loaded before other Sphinx assets -->
<link href="../../_static/styles/theme.css?digest=dfe6caa3a7d634c4db9b" rel="stylesheet" />
<link href="../../_static/styles/bootstrap.css?digest=dfe6caa3a7d634c4db9b" rel="stylesheet" />
<link href="../../_static/styles/pydata-sphinx-theme.css?digest=dfe6caa3a7d634c4db9b" rel="stylesheet" />
<link href="../../_static/vendor/fontawesome/6.5.2/css/all.min.css?digest=dfe6caa3a7d634c4db9b" rel="stylesheet" />
<link rel="preload" as="font" type="font/woff2" crossorigin href="../../_static/vendor/fontawesome/6.5.2/webfonts/fa-solid-900.woff2" />
<link rel="preload" as="font" type="font/woff2" crossorigin href="../../_static/vendor/fontawesome/6.5.2/webfonts/fa-brands-400.woff2" />
<link rel="preload" as="font" type="font/woff2" crossorigin href="../../_static/vendor/fontawesome/6.5.2/webfonts/fa-regular-400.woff2" />
<link rel="stylesheet" type="text/css" href="../../_static/pygments.css?v=8f2a1f02" />
<link rel="stylesheet" type="text/css" href="../../_static/styles/sphinx-book-theme.css?v=eba8b062" />
<link rel="stylesheet" type="text/css" href="../../_static/nbsphinx-code-cells.css?v=2aa19091" />
<link rel="stylesheet" type="text/css" href="../../_static/custom.css?v=f8244a84" />
<!-- Pre-loaded scripts that we'll load fully later -->
<link rel="preload" as="script" href="../../_static/scripts/bootstrap.js?digest=dfe6caa3a7d634c4db9b" />
<link rel="preload" as="script" href="../../_static/scripts/pydata-sphinx-theme.js?digest=dfe6caa3a7d634c4db9b" />
<script src="../../_static/vendor/fontawesome/6.5.2/js/all.min.js?digest=dfe6caa3a7d634c4db9b"></script>
<script src="../../_static/documentation_options.js?v=a51ad17b"></script>
<script src="../../_static/doctools.js?v=9bcbadda"></script>
<script src="../../_static/sphinx_highlight.js?v=dc90522c"></script>
<script src="../../_static/scripts/sphinx-book-theme.js?v=887ef09a"></script>
<script crossorigin="anonymous" integrity="sha256-Ae2Vz/4ePdIu6ZyI/5ZGsYnb+m0JlOmKPjt6XZ9JJkA=" src="https://cdnjs.cloudflare.com/ajax/libs/require.js/2.3.4/require.min.js"></script>
<script>window.MathJax = {"tex": {"inlineMath": [["$", "$"], ["\\(", "\\)"]], "processEscapes": true}, "options": {"ignoreHtmlClass": "tex2jax_ignore|mathjax_ignore|document", "processHtmlClass": "tex2jax_process|mathjax_process|math|output_area"}}</script>
<script defer="defer" src="https://cdn.jsdelivr.net/npm/mathjax@3/es5/tex-mml-chtml.js"></script>
<script>DOCUMENTATION_OPTIONS.pagename = 'guide/solvers';</script>
<link rel="index" title="Index" href="../../genindex/" />
<link rel="search" title="Search" href="../../search/" />
<link rel="next" title="10. Benchmark Problems" href="../../api/problems/" />
<link rel="prev" title="8. Primal Components" href="../primal/" />
<meta name="viewport" content="width=device-width, initial-scale=1"/>
<meta name="docsearch:language" content="en"/>
</head>
<body data-bs-spy="scroll" data-bs-target=".bd-toc-nav" data-offset="180" data-bs-root-margin="0px 0px -60%" data-default-mode="">
<div id="pst-skip-link" class="skip-link d-print-none"><a href="#main-content">Skip to main content</a></div>
<div id="pst-scroll-pixel-helper"></div>
<button type="button" class="btn rounded-pill" id="pst-back-to-top">
<i class="fa-solid fa-arrow-up"></i>Back to top</button>
<input type="checkbox"
class="sidebar-toggle"
id="pst-primary-sidebar-checkbox"/>
<label class="overlay overlay-primary" for="pst-primary-sidebar-checkbox"></label>
<input type="checkbox"
class="sidebar-toggle"
id="pst-secondary-sidebar-checkbox"/>
<label class="overlay overlay-secondary" for="pst-secondary-sidebar-checkbox"></label>
<div class="search-button__wrapper">
<div class="search-button__overlay"></div>
<div class="search-button__search-container">
<form class="bd-search d-flex align-items-center"
action="../../search/"
method="get">
<i class="fa-solid fa-magnifying-glass"></i>
<input type="search"
class="form-control"
name="q"
id="search-input"
placeholder="Search..."
aria-label="Search..."
autocomplete="off"
autocorrect="off"
autocapitalize="off"
spellcheck="false"/>
<span class="search-button__kbd-shortcut"><kbd class="kbd-shortcut__modifier">Ctrl</kbd>+<kbd>K</kbd></span>
</form></div>
</div>
<div class="pst-async-banner-revealer d-none">
<aside id="bd-header-version-warning" class="d-none d-print-none" aria-label="Version warning"></aside>
</div>
<header class="bd-header navbar navbar-expand-lg bd-navbar d-print-none">
</header>
<div class="bd-container">
<div class="bd-container__inner bd-page-width">
<div class="bd-sidebar-primary bd-sidebar">
<div class="sidebar-header-items sidebar-primary__section">
</div>
<div class="sidebar-primary-items__start sidebar-primary__section">
<div class="sidebar-primary-item">
<a class="navbar-brand logo" href="../../">
<p class="title logo__title">MIPLearn 0.4</p>
</a></div>
<div class="sidebar-primary-item">
<script>
document.write(`
<button class="btn search-button-field search-button__button" title="Search" aria-label="Search" data-bs-placement="bottom" data-bs-toggle="tooltip">
<i class="fa-solid fa-magnifying-glass"></i>
<span class="search-button__default-text">Search</span>
<span class="search-button__kbd-shortcut"><kbd class="kbd-shortcut__modifier">Ctrl</kbd>+<kbd class="kbd-shortcut__modifier">K</kbd></span>
</button>
`);
</script></div>
<div class="sidebar-primary-item"><nav class="bd-links bd-docs-nav" aria-label="Main">
<div class="bd-toc-item navbar-nav active">
<p aria-level="2" class="caption" role="heading"><span class="caption-text">Tutorials</span></p>
<ul class="nav bd-sidenav">
<li class="toctree-l1"><a class="reference internal" href="../../tutorials/getting-started-pyomo/">1. Getting started (Pyomo)</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../tutorials/getting-started-gurobipy/">2. Getting started (Gurobipy)</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../tutorials/getting-started-jump/">3. Getting started (JuMP)</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../tutorials/cuts-gurobipy/">4. User cuts and lazy constraints</a></li>
</ul>
<p aria-level="2" class="caption" role="heading"><span class="caption-text">User Guide</span></p>
<ul class="current nav bd-sidenav">
<li class="toctree-l1"><a class="reference internal" href="../problems/">5. Benchmark Problems</a></li>
<li class="toctree-l1"><a class="reference internal" href="../collectors/">6. Training Data Collectors</a></li>
<li class="toctree-l1"><a class="reference internal" href="../features/">7. Feature Extractors</a></li>
<li class="toctree-l1"><a class="reference internal" href="../primal/">8. Primal Components</a></li>
<li class="toctree-l1 current active"><a class="current reference internal" href="#">9. Learning Solver</a></li>
</ul>
<p aria-level="2" class="caption" role="heading"><span class="caption-text">Python API Reference</span></p>
<ul class="nav bd-sidenav">
<li class="toctree-l1"><a class="reference internal" href="../../api/problems/">10. Benchmark Problems</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../api/collectors/">11. Collectors &amp; Extractors</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../api/components/">12. Components</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../api/solvers/">13. Solvers</a></li>
<li class="toctree-l1"><a class="reference internal" href="../../api/helpers/">14. Helpers</a></li>
</ul>
</div>
</nav></div>
</div>
<div class="sidebar-primary-items__end sidebar-primary__section">
</div>
<div id="rtd-footer-container"></div>
</div>
<main id="main-content" class="bd-main" role="main">
<div class="sbt-scroll-pixel-helper"></div>
<div class="bd-content">
<div class="bd-article-container">
<div class="bd-header-article d-print-none">
<div class="header-article-items header-article__inner">
<div class="header-article-items__start">
<div class="header-article-item"><button class="sidebar-toggle primary-toggle btn btn-sm" title="Toggle primary sidebar" data-bs-placement="bottom" data-bs-toggle="tooltip">
<span class="fa-solid fa-bars"></span>
</button></div>
</div>
<div class="header-article-items__end">
<div class="header-article-item">
<div class="article-header-buttons">
<div class="dropdown dropdown-download-buttons">
<button class="btn dropdown-toggle" type="button" data-bs-toggle="dropdown" aria-expanded="false" aria-label="Download this page">
<i class="fas fa-download"></i>
</button>
<ul class="dropdown-menu">
<li><a href="../../_sources/guide/solvers.ipynb" target="_blank"
class="btn btn-sm btn-download-source-button dropdown-item"
title="Download source file"
data-bs-placement="left" data-bs-toggle="tooltip"
>
<span class="btn__icon-container">
<i class="fas fa-file"></i>
</span>
<span class="btn__text-container">.ipynb</span>
</a>
</li>
<li>
<button onclick="window.print()"
class="btn btn-sm btn-download-pdf-button dropdown-item"
title="Print to PDF"
data-bs-placement="left" data-bs-toggle="tooltip"
>
<span class="btn__icon-container">
<i class="fas fa-file-pdf"></i>
</span>
<span class="btn__text-container">.pdf</span>
</button>
</li>
</ul>
</div>
<button onclick="toggleFullScreen()"
class="btn btn-sm btn-fullscreen-button"
title="Fullscreen mode"
data-bs-placement="bottom" data-bs-toggle="tooltip"
>
<span class="btn__icon-container">
<i class="fas fa-expand"></i>
</span>
</button>
<script>
document.write(`
<button class="btn btn-sm nav-link pst-navbar-icon theme-switch-button" title="light/dark" aria-label="light/dark" data-bs-placement="bottom" data-bs-toggle="tooltip">
<i class="theme-switch fa-solid fa-sun fa-lg" data-mode="light"></i>
<i class="theme-switch fa-solid fa-moon fa-lg" data-mode="dark"></i>
<i class="theme-switch fa-solid fa-circle-half-stroke fa-lg" data-mode="auto"></i>
</button>
`);
</script>
<script>
document.write(`
<button class="btn btn-sm pst-navbar-icon search-button search-button__button" title="Search" aria-label="Search" data-bs-placement="bottom" data-bs-toggle="tooltip">
<i class="fa-solid fa-magnifying-glass fa-lg"></i>
</button>
`);
</script>
<button class="sidebar-toggle secondary-toggle btn btn-sm" title="Toggle secondary sidebar" data-bs-placement="bottom" data-bs-toggle="tooltip">
<span class="fa-solid fa-list"></span>
</button>
</div></div>
</div>
</div>
</div>
<div id="jb-print-docs-body" class="onlyprint">
<h1>Learning Solver</h1>
<!-- Table of contents -->
<div id="print-main-content">
<div id="jb-print-toc">
<div>
<h2> Contents </h2>
</div>
<nav aria-label="Page">
<ul class="visible nav section-nav flex-column">
<li class="toc-h2 nav-item toc-entry"><a class="reference internal nav-link" href="#Configuring-the-solver">9.1. Configuring the solver</a></li>
<li class="toc-h2 nav-item toc-entry"><a class="reference internal nav-link" href="#Training-and-solving-new-instances">9.2. Training and solving new instances</a></li>
<li class="toc-h2 nav-item toc-entry"><a class="reference internal nav-link" href="#Complete-example">9.3. Complete example</a></li>
</ul>
</nav>
</div>
</div>
</div>
<div id="searchbox"></div>
<article class="bd-article">
<section id="Learning-Solver">
<h1><span class="section-number">9. </span>Learning Solver<a class="headerlink" href="#Learning-Solver" title="Link to this heading">#</a></h1>
<p>On previous pages, we discussed various components of the MIPLearn framework, including training data collectors, feature extractors, and individual machine learning components. In this page, we introduce <strong>LearningSolver</strong>, the main class of the framework which integrates all the aforementioned components into a cohesive whole. Using <strong>LearningSolver</strong> involves three steps: (i) configuring the solver; (ii) training the ML components; and (iii) solving new MIP instances. In the following, we
describe each of these steps, then conclude with a complete runnable example.</p>
<section id="Configuring-the-solver">
<h2><span class="section-number">9.1. </span>Configuring the solver<a class="headerlink" href="#Configuring-the-solver" title="Link to this heading">#</a></h2>
<p><strong>LearningSolver</strong> is composed by multiple individual machine learning components, each targeting a different part of the solution process, or implementing a different machine learning strategy. This architecture allows strategies to be easily enabled, disabled or customized, making the framework flexible. By default, no components are provided and <strong>LearningSolver</strong> is equivalent to a traditional MIP solver. To specify additional components, the <code class="docutils literal notranslate"><span class="pre">components</span></code> constructor argument may be used:</p>
<div class="highlight-python notranslate"><div class="highlight"><pre><span></span><span class="n">solver</span> <span class="o">=</span> <span class="n">LearningSolver</span><span class="p">(</span>
<span class="n">components</span><span class="o">=</span><span class="p">[</span>
<span class="n">comp1</span><span class="p">,</span>
<span class="n">comp2</span><span class="p">,</span>
<span class="n">comp3</span><span class="p">,</span>
<span class="p">]</span>
<span class="p">)</span>
</pre></div>
</div>
<p>In this example, three components <code class="docutils literal notranslate"><span class="pre">comp1</span></code>, <code class="docutils literal notranslate"><span class="pre">comp2</span></code> and <code class="docutils literal notranslate"><span class="pre">comp3</span></code> are provided. The strategies implemented by these components are applied sequentially when solving the problem. For example, <code class="docutils literal notranslate"><span class="pre">comp1</span></code> and <code class="docutils literal notranslate"><span class="pre">comp2</span></code> could fix a subset of decision variables, while <code class="docutils literal notranslate"><span class="pre">comp3</span></code> constructs a warm start for the remaining problem.</p>
</section>
<section id="Training-and-solving-new-instances">
<h2><span class="section-number">9.2. </span>Training and solving new instances<a class="headerlink" href="#Training-and-solving-new-instances" title="Link to this heading">#</a></h2>
<p>Once a solver is configured, its ML components need to be trained. This can be achieved by the <code class="docutils literal notranslate"><span class="pre">solver.fit</span></code> method, as illustrated below. The method accepts a list of HDF5 files and trains each individual component sequentially. Once the solver is trained, new instances can be solved using <code class="docutils literal notranslate"><span class="pre">solver.optimize</span></code>. The method returns a dictionary of statistics collected by each component, such as the number of variables fixed.</p>
<div class="highlight-python notranslate"><div class="highlight"><pre><span></span><span class="c1"># Build instances</span>
<span class="n">train_data</span> <span class="o">=</span> <span class="o">...</span>
<span class="n">test_data</span> <span class="o">=</span> <span class="o">...</span>
<span class="c1"># Collect training data</span>
<span class="n">bc</span> <span class="o">=</span> <span class="n">BasicCollector</span><span class="p">()</span>
<span class="n">bc</span><span class="o">.</span><span class="n">collect</span><span class="p">(</span><span class="n">train_data</span><span class="p">,</span> <span class="n">build_model</span><span class="p">)</span>
<span class="c1"># Build solver</span>
<span class="n">solver</span> <span class="o">=</span> <span class="n">LearningSolver</span><span class="p">(</span><span class="o">...</span><span class="p">)</span>
<span class="c1"># Train components</span>
<span class="n">solver</span><span class="o">.</span><span class="n">fit</span><span class="p">(</span><span class="n">train_data</span><span class="p">)</span>
<span class="c1"># Solve a new test instance</span>
<span class="n">stats</span> <span class="o">=</span> <span class="n">solver</span><span class="o">.</span><span class="n">optimize</span><span class="p">(</span><span class="n">test_data</span><span class="p">[</span><span class="mi">0</span><span class="p">],</span> <span class="n">build_model</span><span class="p">)</span>
</pre></div>
</div>
</section>
<section id="Complete-example">
<h2><span class="section-number">9.3. </span>Complete example<a class="headerlink" href="#Complete-example" title="Link to this heading">#</a></h2>
<p>In the example below, we illustrate the usage of <strong>LearningSolver</strong> by building instances of the Traveling Salesman Problem, collecting training data, training the ML components, then solving a new instance.</p>
<div class="nbinput docutils container">
<div class="prompt highlight-none notranslate"><div class="highlight"><pre><span></span>[1]:
</pre></div>
</div>
<div class="input_area highlight-ipython3 notranslate"><div class="highlight"><pre><span></span><span class="kn">import</span><span class="w"> </span><span class="nn">random</span>
<span class="kn">import</span><span class="w"> </span><span class="nn">numpy</span><span class="w"> </span><span class="k">as</span><span class="w"> </span><span class="nn">np</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">scipy.stats</span><span class="w"> </span><span class="kn">import</span> <span class="n">uniform</span><span class="p">,</span> <span class="n">randint</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">sklearn.linear_model</span><span class="w"> </span><span class="kn">import</span> <span class="n">LogisticRegression</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">miplearn.classifiers.minprob</span><span class="w"> </span><span class="kn">import</span> <span class="n">MinProbabilityClassifier</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">miplearn.classifiers.singleclass</span><span class="w"> </span><span class="kn">import</span> <span class="n">SingleClassFix</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">miplearn.collectors.basic</span><span class="w"> </span><span class="kn">import</span> <span class="n">BasicCollector</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">miplearn.components.primal.actions</span><span class="w"> </span><span class="kn">import</span> <span class="n">SetWarmStart</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">miplearn.components.primal.indep</span><span class="w"> </span><span class="kn">import</span> <span class="n">IndependentVarsPrimalComponent</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">miplearn.extractors.AlvLouWeh2017</span><span class="w"> </span><span class="kn">import</span> <span class="n">AlvLouWeh2017Extractor</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">miplearn.io</span><span class="w"> </span><span class="kn">import</span> <span class="n">write_pkl_gz</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">miplearn.problems.tsp</span><span class="w"> </span><span class="kn">import</span> <span class="p">(</span>
<span class="n">TravelingSalesmanGenerator</span><span class="p">,</span>
<span class="n">build_tsp_model_gurobipy</span><span class="p">,</span>
<span class="p">)</span>
<span class="kn">from</span><span class="w"> </span><span class="nn">miplearn.solvers.learning</span><span class="w"> </span><span class="kn">import</span> <span class="n">LearningSolver</span>
<span class="c1"># Set random seed to make example reproducible.</span>
<span class="n">random</span><span class="o">.</span><span class="n">seed</span><span class="p">(</span><span class="mi">42</span><span class="p">)</span>
<span class="n">np</span><span class="o">.</span><span class="n">random</span><span class="o">.</span><span class="n">seed</span><span class="p">(</span><span class="mi">42</span><span class="p">)</span>
<span class="c1"># Generate a few instances of the traveling salesman problem.</span>
<span class="n">data</span> <span class="o">=</span> <span class="n">TravelingSalesmanGenerator</span><span class="p">(</span>
<span class="n">n</span><span class="o">=</span><span class="n">randint</span><span class="p">(</span><span class="n">low</span><span class="o">=</span><span class="mi">10</span><span class="p">,</span> <span class="n">high</span><span class="o">=</span><span class="mi">11</span><span class="p">),</span>
<span class="n">x</span><span class="o">=</span><span class="n">uniform</span><span class="p">(</span><span class="n">loc</span><span class="o">=</span><span class="mf">0.0</span><span class="p">,</span> <span class="n">scale</span><span class="o">=</span><span class="mf">1000.0</span><span class="p">),</span>
<span class="n">y</span><span class="o">=</span><span class="n">uniform</span><span class="p">(</span><span class="n">loc</span><span class="o">=</span><span class="mf">0.0</span><span class="p">,</span> <span class="n">scale</span><span class="o">=</span><span class="mf">1000.0</span><span class="p">),</span>
<span class="n">gamma</span><span class="o">=</span><span class="n">uniform</span><span class="p">(</span><span class="n">loc</span><span class="o">=</span><span class="mf">0.90</span><span class="p">,</span> <span class="n">scale</span><span class="o">=</span><span class="mf">0.20</span><span class="p">),</span>
<span class="n">fix_cities</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span>
<span class="nb">round</span><span class="o">=</span><span class="kc">True</span><span class="p">,</span>
<span class="p">)</span><span class="o">.</span><span class="n">generate</span><span class="p">(</span><span class="mi">50</span><span class="p">)</span>
<span class="c1"># Save instance data to data/tsp/00000.pkl.gz, data/tsp/00001.pkl.gz, ...</span>
<span class="n">all_data</span> <span class="o">=</span> <span class="n">write_pkl_gz</span><span class="p">(</span><span class="n">data</span><span class="p">,</span> <span class="s2">&quot;data/tsp&quot;</span><span class="p">)</span>
<span class="c1"># Split train/test data</span>
<span class="n">train_data</span> <span class="o">=</span> <span class="n">all_data</span><span class="p">[:</span><span class="mi">40</span><span class="p">]</span>
<span class="n">test_data</span> <span class="o">=</span> <span class="n">all_data</span><span class="p">[</span><span class="mi">40</span><span class="p">:]</span>
<span class="c1"># Collect training data</span>
<span class="n">bc</span> <span class="o">=</span> <span class="n">BasicCollector</span><span class="p">()</span>
<span class="n">bc</span><span class="o">.</span><span class="n">collect</span><span class="p">(</span><span class="n">train_data</span><span class="p">,</span> <span class="n">build_tsp_model_gurobipy</span><span class="p">,</span> <span class="n">n_jobs</span><span class="o">=</span><span class="mi">4</span><span class="p">)</span>
<span class="c1"># Build learning solver</span>
<span class="n">solver</span> <span class="o">=</span> <span class="n">LearningSolver</span><span class="p">(</span>
<span class="n">components</span><span class="o">=</span><span class="p">[</span>
<span class="n">IndependentVarsPrimalComponent</span><span class="p">(</span>
<span class="n">base_clf</span><span class="o">=</span><span class="n">SingleClassFix</span><span class="p">(</span>
<span class="n">MinProbabilityClassifier</span><span class="p">(</span>
<span class="n">base_clf</span><span class="o">=</span><span class="n">LogisticRegression</span><span class="p">(),</span>
<span class="n">thresholds</span><span class="o">=</span><span class="p">[</span><span class="mf">0.95</span><span class="p">,</span> <span class="mf">0.95</span><span class="p">],</span>
<span class="p">),</span>
<span class="p">),</span>
<span class="n">extractor</span><span class="o">=</span><span class="n">AlvLouWeh2017Extractor</span><span class="p">(),</span>
<span class="n">action</span><span class="o">=</span><span class="n">SetWarmStart</span><span class="p">(),</span>
<span class="p">)</span>
<span class="p">]</span>
<span class="p">)</span>
<span class="c1"># Train ML models</span>
<span class="n">solver</span><span class="o">.</span><span class="n">fit</span><span class="p">(</span><span class="n">train_data</span><span class="p">)</span>
<span class="c1"># Solve a test instance</span>
<span class="n">solver</span><span class="o">.</span><span class="n">optimize</span><span class="p">(</span><span class="n">test_data</span><span class="p">[</span><span class="mi">0</span><span class="p">],</span> <span class="n">build_tsp_model_gurobipy</span><span class="p">);</span>
</pre></div>
</div>
</div>
<div class="nboutput nblast docutils container">
<div class="prompt empty docutils container">
</div>
<div class="output_area docutils container">
<div class="highlight"><pre>
Restricted license - for non-production use only - expires 2026-11-23
Gurobi Optimizer version 12.0.2 build v12.0.2rc0 (linux64 - &#34;Ubuntu 22.04.4 LTS&#34;)
CPU model: 13th Gen Intel(R) Core(TM) i7-13800H, instruction set [SSE2|AVX|AVX2]
Thread count: 10 physical cores, 20 logical processors, using up to 20 threads
Optimize a model with 10 rows, 45 columns and 90 nonzeros
Model fingerprint: 0x6ddcd141
Coefficient statistics:
Matrix range [1e+00, 1e+00]
Objective range [4e+01, 1e+03]
Bounds range [1e+00, 1e+00]
RHS range [2e+00, 2e+00]
Presolve time: 0.00s
Presolved: 10 rows, 45 columns, 90 nonzeros
Iteration Objective Primal Inf. Dual Inf. Time
0 6.3600000e+02 1.700000e+01 0.000000e+00 0s
15 2.7610000e+03 0.000000e+00 0.000000e+00 0s
Solved in 15 iterations and 0.01 seconds (0.00 work units)
Optimal objective 2.761000000e+03
User-callback calls 56, time in user-callback 0.00 sec
Set parameter PreCrush to value 1
Set parameter LazyConstraints to value 1
Gurobi Optimizer version 12.0.2 build v12.0.2rc0 (linux64 - &#34;Ubuntu 22.04.4 LTS&#34;)
CPU model: 13th Gen Intel(R) Core(TM) i7-13800H, instruction set [SSE2|AVX|AVX2]
Thread count: 10 physical cores, 20 logical processors, using up to 20 threads
Non-default parameters:
PreCrush 1
LazyConstraints 1
Optimize a model with 10 rows, 45 columns and 90 nonzeros
Model fingerprint: 0x74ca3d0a
Variable types: 0 continuous, 45 integer (45 binary)
Coefficient statistics:
Matrix range [1e+00, 1e+00]
Objective range [4e+01, 1e+03]
Bounds range [1e+00, 1e+00]
RHS range [2e+00, 2e+00]
User MIP start produced solution with objective 2796 (0.00s)
Loaded user MIP start with objective 2796
Presolve time: 0.00s
Presolved: 10 rows, 45 columns, 90 nonzeros
Variable types: 0 continuous, 45 integer (45 binary)
Root relaxation: objective 2.761000e+03, 14 iterations, 0.00 seconds (0.00 work units)
Nodes | Current Node | Objective Bounds | Work
Expl Unexpl | Obj Depth IntInf | Incumbent BestBd Gap | It/Node Time
0 0 2761.00000 0 - 2796.00000 2761.00000 1.25% - 0s
Cutting planes:
Lazy constraints: 3
Explored 1 nodes (14 simplex iterations) in 0.01 seconds (0.00 work units)
Thread count was 20 (of 20 available processors)
Solution count 1: 2796
Optimal solution found (tolerance 1.00e-04)
Best objective 2.796000000000e+03, best bound 2.796000000000e+03, gap 0.0000%
User-callback calls 114, time in user-callback 0.00 sec
</pre></div></div>
</div>
<div class="nbinput nblast docutils container">
<div class="prompt highlight-none notranslate"><div class="highlight"><pre><span></span>[ ]:
</pre></div>
</div>
<div class="input_area highlight-ipython3 notranslate"><div class="highlight"><pre><span></span>
</pre></div>
</div>
</div>
</section>
</section>
</article>
<footer class="prev-next-footer d-print-none">
<div class="prev-next-area">
<a class="left-prev"
href="../primal/"
title="previous page">
<i class="fa-solid fa-angle-left"></i>
<div class="prev-next-info">
<p class="prev-next-subtitle">previous</p>
<p class="prev-next-title"><span class="section-number">8. </span>Primal Components</p>
</div>
</a>
<a class="right-next"
href="../../api/problems/"
title="next page">
<div class="prev-next-info">
<p class="prev-next-subtitle">next</p>
<p class="prev-next-title"><span class="section-number">10. </span>Benchmark Problems</p>
</div>
<i class="fa-solid fa-angle-right"></i>
</a>
</div>
</footer>
</div>
<div class="bd-sidebar-secondary bd-toc"><div class="sidebar-secondary-items sidebar-secondary__inner">
<div class="sidebar-secondary-item">
<div class="page-toc tocsection onthispage">
<i class="fa-solid fa-list"></i> Contents
</div>
<nav class="bd-toc-nav page-toc">
<ul class="visible nav section-nav flex-column">
<li class="toc-h2 nav-item toc-entry"><a class="reference internal nav-link" href="#Configuring-the-solver">9.1. Configuring the solver</a></li>
<li class="toc-h2 nav-item toc-entry"><a class="reference internal nav-link" href="#Training-and-solving-new-instances">9.2. Training and solving new instances</a></li>
<li class="toc-h2 nav-item toc-entry"><a class="reference internal nav-link" href="#Complete-example">9.3. Complete example</a></li>
</ul>
</nav></div>
</div></div>
</div>
<footer class="bd-footer-content">
<div class="bd-footer-content__inner container">
<div class="footer-item">
</div>
<div class="footer-item">
<p class="copyright">
© Copyright 2020-2023, UChicago Argonne, LLC.
<br/>
</p>
</div>
<div class="footer-item">
</div>
<div class="footer-item">
</div>
</div>
</footer>
</main>
</div>
</div>
<!-- Scripts loaded after <body> so the DOM is not blocked -->
<script src="../../_static/scripts/bootstrap.js?digest=dfe6caa3a7d634c4db9b"></script>
<script src="../../_static/scripts/pydata-sphinx-theme.js?digest=dfe6caa3a7d634c4db9b"></script>
<footer class="bd-footer">
</footer>
</body>
</html>