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<div class="title">linear_relaxation.h</div> </div>
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<a href="linear__relaxation_8h.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span>&#160;<span class="comment">// Copyright 2010-2018 Google LLC</span></div>
<div class="line"><a name="l00002"></a><span class="lineno"> 2</span>&#160;<span class="comment">// Licensed under the Apache License, Version 2.0 (the &quot;License&quot;);</span></div>
<div class="line"><a name="l00003"></a><span class="lineno"> 3</span>&#160;<span class="comment">// you may not use this file except in compliance with the License.</span></div>
<div class="line"><a name="l00004"></a><span class="lineno"> 4</span>&#160;<span class="comment">// You may obtain a copy of the License at</span></div>
<div class="line"><a name="l00005"></a><span class="lineno"> 5</span>&#160;<span class="comment">//</span></div>
<div class="line"><a name="l00006"></a><span class="lineno"> 6</span>&#160;<span class="comment">// http://www.apache.org/licenses/LICENSE-2.0</span></div>
<div class="line"><a name="l00007"></a><span class="lineno"> 7</span>&#160;<span class="comment">//</span></div>
<div class="line"><a name="l00008"></a><span class="lineno"> 8</span>&#160;<span class="comment">// Unless required by applicable law or agreed to in writing, software</span></div>
<div class="line"><a name="l00009"></a><span class="lineno"> 9</span>&#160;<span class="comment">// distributed under the License is distributed on an &quot;AS IS&quot; BASIS,</span></div>
<div class="line"><a name="l00010"></a><span class="lineno"> 10</span>&#160;<span class="comment">// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.</span></div>
<div class="line"><a name="l00011"></a><span class="lineno"> 11</span>&#160;<span class="comment">// See the License for the specific language governing permissions and</span></div>
<div class="line"><a name="l00012"></a><span class="lineno"> 12</span>&#160;<span class="comment">// limitations under the License.</span></div>
<div class="line"><a name="l00013"></a><span class="lineno"> 13</span>&#160; </div>
<div class="line"><a name="l00014"></a><span class="lineno"> 14</span>&#160;<span class="preprocessor">#ifndef OR_TOOLS_SAT_LINEAR_RELAXATION_H_</span></div>
<div class="line"><a name="l00015"></a><span class="lineno"> 15</span>&#160;<span class="preprocessor">#define OR_TOOLS_SAT_LINEAR_RELAXATION_H_</span></div>
<div class="line"><a name="l00016"></a><span class="lineno"> 16</span>&#160; </div>
<div class="line"><a name="l00017"></a><span class="lineno"> 17</span>&#160;<span class="preprocessor">#include &lt;vector&gt;</span></div>
<div class="line"><a name="l00018"></a><span class="lineno"> 18</span>&#160; </div>
<div class="line"><a name="l00019"></a><span class="lineno"> 19</span>&#160;<span class="preprocessor">#include &quot;<a class="code" href="cp__model__loader_8h.html">ortools/sat/cp_model_loader.h</a>&quot;</span></div>
<div class="line"><a name="l00020"></a><span class="lineno"> 20</span>&#160;<span class="preprocessor">#include &quot;<a class="code" href="integer_8h.html">ortools/sat/integer.h</a>&quot;</span></div>
<div class="line"><a name="l00021"></a><span class="lineno"> 21</span>&#160;<span class="preprocessor">#include &quot;<a class="code" href="linear__constraint_8h.html">ortools/sat/linear_constraint.h</a>&quot;</span></div>
<div class="line"><a name="l00022"></a><span class="lineno"> 22</span>&#160;<span class="preprocessor">#include &quot;<a class="code" href="linear__programming__constraint_8h.html">ortools/sat/linear_programming_constraint.h</a>&quot;</span></div>
<div class="line"><a name="l00023"></a><span class="lineno"> 23</span>&#160;<span class="preprocessor">#include &quot;<a class="code" href="sat_2model_8h.html">ortools/sat/model.h</a>&quot;</span></div>
<div class="line"><a name="l00024"></a><span class="lineno"> 24</span>&#160; </div>
<div class="line"><a name="l00025"></a><span class="lineno"> 25</span>&#160;<span class="keyword">namespace </span><a class="code" href="namespaceoperations__research.html">operations_research</a> {</div>
<div class="line"><a name="l00026"></a><span class="lineno"> 26</span>&#160;<span class="keyword">namespace </span>sat {</div>
<div class="line"><a name="l00027"></a><span class="lineno"> 27</span>&#160; </div>
<div class="line"><a name="l00028"></a><span class="lineno"><a class="line" href="structoperations__research_1_1sat_1_1LinearRelaxation.html"> 28</a></span>&#160;<span class="keyword">struct </span><a class="code" href="structoperations__research_1_1sat_1_1LinearRelaxation.html">LinearRelaxation</a> {</div>
<div class="line"><a name="l00029"></a><span class="lineno"><a class="line" href="structoperations__research_1_1sat_1_1LinearRelaxation.html#a787dea05b34122764c7fb5fd13e9a1c9"> 29</a></span>&#160; std::vector&lt;LinearConstraint&gt; <a class="code" href="structoperations__research_1_1sat_1_1LinearRelaxation.html#a787dea05b34122764c7fb5fd13e9a1c9">linear_constraints</a>;</div>
<div class="line"><a name="l00030"></a><span class="lineno"><a class="line" href="structoperations__research_1_1sat_1_1LinearRelaxation.html#a0bffb74eb458b339aa75f20b6c982a60"> 30</a></span>&#160; std::vector&lt;std::vector&lt;Literal&gt;&gt; <a class="code" href="structoperations__research_1_1sat_1_1LinearRelaxation.html#a0bffb74eb458b339aa75f20b6c982a60">at_most_ones</a>;</div>
<div class="line"><a name="l00031"></a><span class="lineno"><a class="line" href="structoperations__research_1_1sat_1_1LinearRelaxation.html#ae6fdc05264dc58e553116fe3d9dbe236"> 31</a></span>&#160; std::vector&lt;CutGenerator&gt; <a class="code" href="structoperations__research_1_1sat_1_1LinearRelaxation.html#ae6fdc05264dc58e553116fe3d9dbe236">cut_generators</a>;</div>
<div class="line"><a name="l00032"></a><span class="lineno"> 32</span>&#160;};</div>
<div class="line"><a name="l00033"></a><span class="lineno"> 33</span>&#160; </div>
<div class="line"><a name="l00034"></a><span class="lineno"> 34</span>&#160;<span class="comment">// If the given IntegerVariable is fully encoded (li &lt;=&gt; var == xi), adds to the</span></div>
<div class="line"><a name="l00035"></a><span class="lineno"> 35</span>&#160;<span class="comment">// constraints vector the following linear relaxation of its encoding:</span></div>
<div class="line"><a name="l00036"></a><span class="lineno"> 36</span>&#160;<span class="comment">// - Sum li == 1</span></div>
<div class="line"><a name="l00037"></a><span class="lineno"> 37</span>&#160;<span class="comment">// - Sum li * xi == var</span></div>
<div class="line"><a name="l00038"></a><span class="lineno"> 38</span>&#160;<span class="comment">// Note that all the literal (li) of the encoding must have an IntegerView,</span></div>
<div class="line"><a name="l00039"></a><span class="lineno"> 39</span>&#160;<span class="comment">// otherwise this function just does nothing.</span></div>
<div class="line"><a name="l00040"></a><span class="lineno"> 40</span>&#160;<span class="comment">//</span></div>
<div class="line"><a name="l00041"></a><span class="lineno"> 41</span>&#160;<span class="comment">// Returns false, if the relaxation couldn&#39;t be added because this variable</span></div>
<div class="line"><a name="l00042"></a><span class="lineno"> 42</span>&#160;<span class="comment">// was not fully encoded or not all its associated literal had a view.</span></div>
<div class="line"><a name="l00043"></a><span class="lineno"> 43</span>&#160;<span class="keywordtype">bool</span> <a class="code" href="namespaceoperations__research_1_1sat.html#a5564bcb1461ad3cbce7f744c3fb58c6b">AppendFullEncodingRelaxation</a>(IntegerVariable <a class="code" href="expr__array_8cc.html#a472a99923cbe11ae7b5a5d157d9ad465">var</a>, <span class="keyword">const</span> <a class="code" href="classoperations__research_1_1sat_1_1Model.html">Model</a>&amp; <a class="code" href="gurobi__interface_8cc.html#a0728f23c9a47655d38e0bf1a2f200bcf">model</a>,</div>
<div class="line"><a name="l00044"></a><span class="lineno"> 44</span>&#160; <a class="code" href="structoperations__research_1_1sat_1_1LinearRelaxation.html">LinearRelaxation</a>* relaxation);</div>
<div class="line"><a name="l00045"></a><span class="lineno"> 45</span>&#160; </div>
<div class="line"><a name="l00046"></a><span class="lineno"> 46</span>&#160;<span class="comment">// When the set of (li &lt;=&gt; var == xi) do not cover the full domain of xi, we</span></div>
<div class="line"><a name="l00047"></a><span class="lineno"> 47</span>&#160;<span class="comment">// do something a bit more involved. Let min/max the min and max value of the</span></div>
<div class="line"><a name="l00048"></a><span class="lineno"> 48</span>&#160;<span class="comment">// domain of var that is NOT part of the encoding. We add:</span></div>
<div class="line"><a name="l00049"></a><span class="lineno"> 49</span>&#160;<span class="comment">// - Sum li &lt;= 1</span></div>
<div class="line"><a name="l00050"></a><span class="lineno"> 50</span>&#160;<span class="comment">// - (Sum li * xi) + (1 - Sum li) * min &lt;= var</span></div>
<div class="line"><a name="l00051"></a><span class="lineno"> 51</span>&#160;<span class="comment">// - var &lt;= (Sum li * xi) + (1 - Sum li) * max</span></div>
<div class="line"><a name="l00052"></a><span class="lineno"> 52</span>&#160;<span class="comment">//</span></div>
<div class="line"><a name="l00053"></a><span class="lineno"> 53</span>&#160;<span class="comment">// Note that if it turns out that the partial encoding is full, this will just</span></div>
<div class="line"><a name="l00054"></a><span class="lineno"> 54</span>&#160;<span class="comment">// use the same encoding as AppendFullEncodingRelaxation(). Any literal that</span></div>
<div class="line"><a name="l00055"></a><span class="lineno"> 55</span>&#160;<span class="comment">// do not have an IntegerView will be skipped, there is no point adding them</span></div>
<div class="line"><a name="l00056"></a><span class="lineno"> 56</span>&#160;<span class="comment">// to the LP if they are not used in any other constraint, the relaxation will</span></div>
<div class="line"><a name="l00057"></a><span class="lineno"> 57</span>&#160;<span class="comment">// have the same &quot;power&quot; without them.</span></div>
<div class="line"><a name="l00058"></a><span class="lineno"> 58</span>&#160;<span class="keywordtype">void</span> <a class="code" href="namespaceoperations__research_1_1sat.html#aa490b08ec514e9c567ff098d53353db1">AppendPartialEncodingRelaxation</a>(IntegerVariable <a class="code" href="expr__array_8cc.html#a472a99923cbe11ae7b5a5d157d9ad465">var</a>, <span class="keyword">const</span> <a class="code" href="classoperations__research_1_1sat_1_1Model.html">Model</a>&amp; <a class="code" href="gurobi__interface_8cc.html#a0728f23c9a47655d38e0bf1a2f200bcf">model</a>,</div>
<div class="line"><a name="l00059"></a><span class="lineno"> 59</span>&#160; <a class="code" href="structoperations__research_1_1sat_1_1LinearRelaxation.html">LinearRelaxation</a>* relaxation);</div>
<div class="line"><a name="l00060"></a><span class="lineno"> 60</span>&#160; </div>
<div class="line"><a name="l00061"></a><span class="lineno"> 61</span>&#160;<span class="comment">// This is a different relaxation that use a partial set of literal li such that</span></div>
<div class="line"><a name="l00062"></a><span class="lineno"> 62</span>&#160;<span class="comment">// (li &lt;=&gt; var &gt;= xi). In which case we use the following encoding:</span></div>
<div class="line"><a name="l00063"></a><span class="lineno"> 63</span>&#160;<span class="comment">// - li &gt;= l_{i+1} for all possible i. Note that the xi need to be sorted.</span></div>
<div class="line"><a name="l00064"></a><span class="lineno"> 64</span>&#160;<span class="comment">// - var &gt;= min + l0 * (x0 - min) + Sum_{i&gt;0} li * (xi - x_{i-1})</span></div>
<div class="line"><a name="l00065"></a><span class="lineno"> 65</span>&#160;<span class="comment">// - and same as above for NegationOf(var) for the upper bound.</span></div>
<div class="line"><a name="l00066"></a><span class="lineno"> 66</span>&#160;<span class="comment">//</span></div>
<div class="line"><a name="l00067"></a><span class="lineno"> 67</span>&#160;<span class="comment">// Like for AppendPartialEncodingRelaxation() we skip any li that do not have</span></div>
<div class="line"><a name="l00068"></a><span class="lineno"> 68</span>&#160;<span class="comment">// an integer view.</span></div>
<div class="line"><a name="l00069"></a><span class="lineno"> 69</span>&#160;<span class="keywordtype">void</span> <a class="code" href="namespaceoperations__research_1_1sat.html#aff14a4092356fceea657393b7b234b7f">AppendPartialGreaterThanEncodingRelaxation</a>(IntegerVariable <a class="code" href="expr__array_8cc.html#a472a99923cbe11ae7b5a5d157d9ad465">var</a>,</div>
<div class="line"><a name="l00070"></a><span class="lineno"> 70</span>&#160; <span class="keyword">const</span> <a class="code" href="classoperations__research_1_1sat_1_1Model.html">Model</a>&amp; <a class="code" href="gurobi__interface_8cc.html#a0728f23c9a47655d38e0bf1a2f200bcf">model</a>,</div>
<div class="line"><a name="l00071"></a><span class="lineno"> 71</span>&#160; <a class="code" href="structoperations__research_1_1sat_1_1LinearRelaxation.html">LinearRelaxation</a>* relaxation);</div>
<div class="line"><a name="l00072"></a><span class="lineno"> 72</span>&#160; </div>
<div class="line"><a name="l00073"></a><span class="lineno"> 73</span>&#160;<span class="comment">// Adds linearization of different types of constraints.</span></div>
<div class="line"><a name="l00074"></a><span class="lineno"> 74</span>&#160;<span class="keywordtype">void</span> <a class="code" href="namespaceoperations__research_1_1sat.html#a94739087f86f5e1b7679d5371d4d9f4b">TryToLinearizeConstraint</a>(<span class="keyword">const</span> CpModelProto&amp; <a class="code" href="cp__model__solver_8cc.html#a6ac76d8a372013f67c4973012948ec84">model_proto</a>,</div>
<div class="line"><a name="l00075"></a><span class="lineno"> 75</span>&#160; <span class="keyword">const</span> ConstraintProto&amp; <a class="code" href="demon__profiler_8cc.html#a05da18ca9c7b657a4a6ea24e07c9b695">ct</a>, <a class="code" href="classoperations__research_1_1sat_1_1Model.html">Model</a>* <a class="code" href="gurobi__interface_8cc.html#a0728f23c9a47655d38e0bf1a2f200bcf">model</a>,</div>
<div class="line"><a name="l00076"></a><span class="lineno"> 76</span>&#160; <span class="keywordtype">int</span> linearization_level,</div>
<div class="line"><a name="l00077"></a><span class="lineno"> 77</span>&#160; <a class="code" href="structoperations__research_1_1sat_1_1LinearRelaxation.html">LinearRelaxation</a>* relaxation);</div>
<div class="line"><a name="l00078"></a><span class="lineno"> 78</span>&#160; </div>
<div class="line"><a name="l00079"></a><span class="lineno"> 79</span>&#160;<span class="comment">// Adds linearization of no overlap constraints. For each pair of intervals, we</span></div>
<div class="line"><a name="l00080"></a><span class="lineno"> 80</span>&#160;<span class="comment">// add linear constraints enforcing precedence of one over other. We check the</span></div>
<div class="line"><a name="l00081"></a><span class="lineno"> 81</span>&#160;<span class="comment">// bounds and only linearize the pairs which are intersecting. We ignore the</span></div>
<div class="line"><a name="l00082"></a><span class="lineno"> 82</span>&#160;<span class="comment">// intervals with enforcement literal. Note that we might create new variables</span></div>
<div class="line"><a name="l00083"></a><span class="lineno"> 83</span>&#160;<span class="comment">// for each pair of intervals and this might cause addition of quadratic number</span></div>
<div class="line"><a name="l00084"></a><span class="lineno"> 84</span>&#160;<span class="comment">// of new variables.</span></div>
<div class="line"><a name="l00085"></a><span class="lineno"> 85</span>&#160;<span class="keywordtype">void</span> <a class="code" href="namespaceoperations__research_1_1sat.html#acc7b292198fce358615d0295cd1c3078">AppendNoOverlapRelaxation</a>(<span class="keyword">const</span> CpModelProto&amp; <a class="code" href="cp__model__solver_8cc.html#a6ac76d8a372013f67c4973012948ec84">model_proto</a>,</div>
<div class="line"><a name="l00086"></a><span class="lineno"> 86</span>&#160; <span class="keyword">const</span> ConstraintProto&amp; <a class="code" href="demon__profiler_8cc.html#a05da18ca9c7b657a4a6ea24e07c9b695">ct</a>,</div>
<div class="line"><a name="l00087"></a><span class="lineno"> 87</span>&#160; <span class="keywordtype">int</span> linearization_level, <a class="code" href="classoperations__research_1_1sat_1_1Model.html">Model</a>* <a class="code" href="gurobi__interface_8cc.html#a0728f23c9a47655d38e0bf1a2f200bcf">model</a>,</div>
<div class="line"><a name="l00088"></a><span class="lineno"> 88</span>&#160; <a class="code" href="structoperations__research_1_1sat_1_1LinearRelaxation.html">LinearRelaxation</a>* relaxation);</div>
<div class="line"><a name="l00089"></a><span class="lineno"> 89</span>&#160; </div>
<div class="line"><a name="l00090"></a><span class="lineno"> 90</span>&#160;<span class="comment">// Adds linearization of int max constraints. This can also be used to linearize</span></div>
<div class="line"><a name="l00091"></a><span class="lineno"> 91</span>&#160;<span class="comment">// int min with negated variables.</span></div>
<div class="line"><a name="l00092"></a><span class="lineno"> 92</span>&#160;<span class="keywordtype">void</span> <a class="code" href="namespaceoperations__research_1_1sat.html#a69d42878d739b511b1abd4843592cdb3">AppendMaxRelaxation</a>(IntegerVariable target,</div>
<div class="line"><a name="l00093"></a><span class="lineno"> 93</span>&#160; <span class="keyword">const</span> std::vector&lt;IntegerVariable&gt;&amp; vars,</div>
<div class="line"><a name="l00094"></a><span class="lineno"> 94</span>&#160; <span class="keywordtype">int</span> linearization_level, <a class="code" href="classoperations__research_1_1sat_1_1Model.html">Model</a>* <a class="code" href="gurobi__interface_8cc.html#a0728f23c9a47655d38e0bf1a2f200bcf">model</a>,</div>
<div class="line"><a name="l00095"></a><span class="lineno"> 95</span>&#160; <a class="code" href="structoperations__research_1_1sat_1_1LinearRelaxation.html">LinearRelaxation</a>* relaxation);</div>
<div class="line"><a name="l00096"></a><span class="lineno"> 96</span>&#160; </div>
<div class="line"><a name="l00097"></a><span class="lineno"> 97</span>&#160;<span class="comment">// Adds linearization of int max constraints. Returns a vector of z vars such</span></div>
<div class="line"><a name="l00098"></a><span class="lineno"> 98</span>&#160;<span class="comment">// that: z_vars[l] == 1 &lt;=&gt; target = exprs[l].</span></div>
<div class="line"><a name="l00099"></a><span class="lineno"> 99</span>&#160;<span class="comment">//</span></div>
<div class="line"><a name="l00100"></a><span class="lineno"> 100</span>&#160;<span class="comment">// Consider the Lin Max constraint with d expressions and n variables in the</span></div>
<div class="line"><a name="l00101"></a><span class="lineno"> 101</span>&#160;<span class="comment">// form: target = max {exprs[l] = Sum (wli * xi + bl)}. l in {1,..,d}.</span></div>
<div class="line"><a name="l00102"></a><span class="lineno"> 102</span>&#160;<span class="comment">// Li = lower bound of xi</span></div>
<div class="line"><a name="l00103"></a><span class="lineno"> 103</span>&#160;<span class="comment">// Ui = upper bound of xi.</span></div>
<div class="line"><a name="l00104"></a><span class="lineno"> 104</span>&#160;<span class="comment">// Let zl be in {0,1} for all l in {1,..,d}.</span></div>
<div class="line"><a name="l00105"></a><span class="lineno"> 105</span>&#160;<span class="comment">// The target = exprs[l] when zl = 1.</span></div>
<div class="line"><a name="l00106"></a><span class="lineno"> 106</span>&#160;<span class="comment">//</span></div>
<div class="line"><a name="l00107"></a><span class="lineno"> 107</span>&#160;<span class="comment">// The following is a valid linearization for Lin Max.</span></div>
<div class="line"><a name="l00108"></a><span class="lineno"> 108</span>&#160;<span class="comment">// target &gt;= exprs[l], for all l in {1,..,d}</span></div>
<div class="line"><a name="l00109"></a><span class="lineno"> 109</span>&#160;<span class="comment">// target &lt;= Sum_i(wki * xi) + Sum_l((Nkl + bl) * zl), for all k in {1,..,d}</span></div>
<div class="line"><a name="l00110"></a><span class="lineno"> 110</span>&#160;<span class="comment">// Where Nkl is a large number defined as:</span></div>
<div class="line"><a name="l00111"></a><span class="lineno"> 111</span>&#160;<span class="comment">// Nkl = Sum_i(max((wli - wki)*Li, (wli - wki)*Ui))</span></div>
<div class="line"><a name="l00112"></a><span class="lineno"> 112</span>&#160;<span class="comment">// = Sum (max corner difference for variable i, target expr k, max expr l)</span></div>
<div class="line"><a name="l00113"></a><span class="lineno"> 113</span>&#160;<span class="comment">// Reference: &quot;Strong mixed-integer programming formulations for trained neural</span></div>
<div class="line"><a name="l00114"></a><span class="lineno"> 114</span>&#160;<span class="comment">// networks&quot; by Ross Anderson et. (https://arxiv.org/pdf/1811.01988.pdf).</span></div>
<div class="line"><a name="l00115"></a><span class="lineno"> 115</span>&#160;<span class="comment">// TODO(user): Support linear expression as target.</span></div>
<div class="line"><a name="l00116"></a><span class="lineno"> 116</span>&#160;std::vector&lt;IntegerVariable&gt; <a class="code" href="namespaceoperations__research_1_1sat.html#a130634b7e74e7c3eee64967e6bd5bb15">AppendLinMaxRelaxation</a>(</div>
<div class="line"><a name="l00117"></a><span class="lineno"> 117</span>&#160; IntegerVariable target, <span class="keyword">const</span> std::vector&lt;LinearExpression&gt;&amp; exprs,</div>
<div class="line"><a name="l00118"></a><span class="lineno"> 118</span>&#160; <a class="code" href="classoperations__research_1_1sat_1_1Model.html">Model</a>* <a class="code" href="gurobi__interface_8cc.html#a0728f23c9a47655d38e0bf1a2f200bcf">model</a>, <a class="code" href="structoperations__research_1_1sat_1_1LinearRelaxation.html">LinearRelaxation</a>* relaxation);</div>
<div class="line"><a name="l00119"></a><span class="lineno"> 119</span>&#160; </div>
<div class="line"><a name="l00120"></a><span class="lineno"> 120</span>&#160;<span class="comment">// Appends linear constraints to the relaxation. This also handles the</span></div>
<div class="line"><a name="l00121"></a><span class="lineno"> 121</span>&#160;<span class="comment">// relaxation of linear constraints with enforcement literals.</span></div>
<div class="line"><a name="l00122"></a><span class="lineno"> 122</span>&#160;<span class="comment">// A linear constraint lb &lt;= ax &lt;= ub with enforcement literals {ei} is relaxed</span></div>
<div class="line"><a name="l00123"></a><span class="lineno"> 123</span>&#160;<span class="comment">// as following.</span></div>
<div class="line"><a name="l00124"></a><span class="lineno"> 124</span>&#160;<span class="comment">// lb &lt;= (Sum Negated(ei) * (lb - implied_lb)) + ax &lt;= inf</span></div>
<div class="line"><a name="l00125"></a><span class="lineno"> 125</span>&#160;<span class="comment">// -inf &lt;= (Sum Negated(ei) * (ub - implied_ub)) + ax &lt;= ub</span></div>
<div class="line"><a name="l00126"></a><span class="lineno"> 126</span>&#160;<span class="comment">// Where implied_lb and implied_ub are trivial lower and upper bounds of the</span></div>
<div class="line"><a name="l00127"></a><span class="lineno"> 127</span>&#160;<span class="comment">// constraint.</span></div>
<div class="line"><a name="l00128"></a><span class="lineno"> 128</span>&#160;<span class="keywordtype">void</span> <a class="code" href="namespaceoperations__research_1_1sat.html#a1d3cc11409a085647b7fb94b62a82ae5">AppendLinearConstraintRelaxation</a>(<span class="keyword">const</span> ConstraintProto&amp; constraint_proto,</div>
<div class="line"><a name="l00129"></a><span class="lineno"> 129</span>&#160; <span class="keyword">const</span> <span class="keywordtype">int</span> linearization_level,</div>
<div class="line"><a name="l00130"></a><span class="lineno"> 130</span>&#160; <span class="keyword">const</span> <a class="code" href="classoperations__research_1_1sat_1_1Model.html">Model</a>&amp; <a class="code" href="gurobi__interface_8cc.html#a0728f23c9a47655d38e0bf1a2f200bcf">model</a>,</div>
<div class="line"><a name="l00131"></a><span class="lineno"> 131</span>&#160; <a class="code" href="structoperations__research_1_1sat_1_1LinearRelaxation.html">LinearRelaxation</a>* relaxation);</div>
<div class="line"><a name="l00132"></a><span class="lineno"> 132</span>&#160; </div>
<div class="line"><a name="l00133"></a><span class="lineno"> 133</span>&#160;} <span class="comment">// namespace sat</span></div>
<div class="line"><a name="l00134"></a><span class="lineno"> 134</span>&#160;} <span class="comment">// namespace operations_research</span></div>
<div class="line"><a name="l00135"></a><span class="lineno"> 135</span>&#160; </div>
<div class="line"><a name="l00136"></a><span class="lineno"> 136</span>&#160;<span class="preprocessor">#endif // OR_TOOLS_SAT_LINEAR_RELAXATION_H_</span></div>
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<div class="ttc" id="aexpr__array_8cc_html_a472a99923cbe11ae7b5a5d157d9ad465"><div class="ttname"><a href="expr__array_8cc.html#a472a99923cbe11ae7b5a5d157d9ad465">var</a></div><div class="ttdeci">IntVar * var</div><div class="ttdef"><b>Definition:</b> <a href="expr__array_8cc_source.html#l01858">expr_array.cc:1858</a></div></div>
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