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<div>I have encountered this, yes. But I’m not sure what causes it. However, I could fix some convergence problems by normalising my constraints, objective and optimisation variables.</div>

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<div>Filip</div>

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<span style="font-weight:bold">From: </span>Ipopt <<a href="mailto:ipopt-bounces@coin-or.org">ipopt-bounces@coin-or.org</a>> on behalf of "Nedialkov, Ned" <<a href="mailto:nedialk@mcmaster.ca">nedialk@mcmaster.ca</a>><br>

<span style="font-weight:bold">Date: </span>Thursday, 14 December 2017 at 03:42<br>

<span style="font-weight:bold">To: </span>"<a href="mailto:Ipopt@list.coin-or.org">Ipopt@list.coin-or.org</a>" <<a href="mailto:Ipopt@list.coin-or.org">Ipopt@list.coin-or.org</a>><br>

<span style="font-weight:bold">Subject: </span>[Ipopt] linear solvers in IPOPT<br>

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<div class="">Hi All, </div>

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<div class="">I am wondering if any of you has encountered a situation when IPOPT does not converge with </div>

<div class="">a particular linear solver (e.g. ma27) but does with another linear solver?</div>

<div class="">If so, is there any rule of thumb what solver to chose or which one is likely to work best?</div>

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<div class="">Best regards, </div>

<div class=""><span style="orphans: 2; text-align: -webkit-auto; widows: 2;" class="">Ned Nedialkov</span></div>

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Professor<br class="">

Department of Computing and Software<br class="">

McMaster University <br class="">

Hamilton, Ontario, L8S 4K1<br class="">

CANADA <br class="">

Phone<span class="Apple-tab-span" style="white-space: pre;"> </span>1-905-525-9140, ext. 24161<br class="">

URL: <a href="https://urldefense.proofpoint.com/v2/url?u=http-3A__www.cas.mcmaster.ca_-7Enedialk_&d=DwMFAg&c=Ngd-ta5yRYsqeUsEDgxhcqsYYY1Xs5ogLxWPA_2Wlc4&r=JMOL7a1AIeo7iHtDqG-xuMTq3Gl1f1b5TKp74zFmuSI&m=urixrM9373WaNtlBN7Ejl8Z8G95rj8AP0M65C-6bs6s&s=LW_NDIf-JP1jPw3Huj3PU7iID35teHYlUcCk9n1ek6g&e=" class="">

http://www.cas.mcmaster.ca/~nedialk/</a><br class="">

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