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</o:shapelayout></xml><![endif]--></head><body lang=ES link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Dear IPopt user community:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I am currently working on a project using the IPopt minimization under contraints.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>An example for visual studio “csipopt” converges successfully. <o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Yet - for the sake of benchmarking - I am trying to minimize the 1D polynomial f(x) = x + x<sup>2</sup>/2 under the constraints -10<x<10 and with initial guess x = 1.<o:p></o:p></p><p class=MsoNormal>Accordingly the gradient is g(x) = 1 + x and the hessian h(x) = 1. IPopt fails to find the minimum x=-1/4 as the iterations deviate only marginally from the initial value as shown by the attached <span style='color:#1F497D'>file</span>.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Please advise me how to proceed. I suspect this must be a minor option setting.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thank you.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Sebastian Ferrera, Chile<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>