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Hello, i'm using Couenne in Atom/Juno, through Julia language, to solve some MINLP problems.</div>
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But i have an issue with this following problem (it's a random problem i just wrote to test the Couenne solver in Atom):</div>
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<span>## Solve test problem<br>
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<div> #<br>
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<div> # min 100 * (x5 - (0.5 + x4) ^ 2) ^ 2 + (1 - x4) ^ 2<br>
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<div> # s.t. x4*x3 + x5*x1 <= 20<br>
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<div> # 5*x1 - 2*x5 + 3*x3 <= 17<br>
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<div> # x4, x5 binary<br>
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<div> # 0 <= x1 <= 3<br>
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<div> # 0 <= x2 <= 5<br>
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<div> # 0 <= x3 <= 10<br>
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<span> ##</span><br>
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<span>The problem is being solved to optimal point, but my binary variable x4 is not assuming a binary value. Here is the solution i found:</span></div>
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<span>x1 = 1</span></div>
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<span>x2 = 2.5</span></div>
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<span>x3 = 2</span></div>
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<span>x4 = 0.50124...</span></div>
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<span>x5 = 1</span></div>
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<span>Why is this happening? How can i fix this?</span></div>
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<span>Thanks in advance,</span></div>
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<span>Murilo Souza</span></div>
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