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<p class=MsoNormal>To Whom it May Concern,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I have downloaded the precompiled DLLs for Ipopt version
3.8.1 and built a VB.NET wrapper around them within Visual Studio 2008
Professional. Within my wrapper I have incorporated a “multi-start”
feature that loops through many uniformly distributed starting points within
the defined design space for a given optimization problem. Inside of this
looping I am creating a new Ipopt problem with the DLL’s “CreateIpoptProblem”
function, solving with “IpoptSolve”, and then clearing the problem
with “FreeIpoptProblem” before continuing to the next starting
point. I am then tracking the best objective function and its
corresponding design variable optimums in an effort to find a global minimum
within the design space. I have, however, encountered an issue where in
the execution of my project gets stuck in an infinite loop within the Ipopt DLL’s
“IpoptSolve” function. This occurs for both the debug and
release versions of the DLL and the starting point for which the infinite loop
occurs appears to be dependent on the option tolerances that I define. I
would greatly appreciate any assistance from anybody that has encountered this
issue previously, or has recommendations for a solution, and could point me in
the right direction.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thank you in advance,<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'>Chris
Magdziasz<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'>Spiritech
Advanced Products, Inc.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'>Phone:
561-741-3441<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'>Fax:
561-741-3442<o:p></o:p></span></p>
<p class=MsoNormal><o:p> </o:p></p>
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