<div dir="ltr">Hi,<div><br></div><div>I have a couple of questions regarding the C++ interface of Ipopt:</div><div><br></div><div>1) Is there a convenient way to pass auxiliary data to Ipopt when interfacing through C++?</div>
<div><br></div><div>I have been using the MatlabInterface previously, and as seen in "/Ipopt/contrib/MatlabInterface/examples/lasso.m", by assigning a value to "auxdata" in the solver options, this parameter can be passed and unpacked in any of the callbacks (objective, gradient, etc...) to access extra information. What will the equivalent for C++ interface be?</div>
<div><br></div><div>2) If I use "limiteed-memory" mode for "hessian_approximation" option, do I still need to implement all the functions mentioned in the tutorial? (<a href="http://www.coin-or.org/Ipopt/documentation/node32.html">http://www.coin-or.org/Ipopt/documentation/node32.html</a>) I assume that I won't need "eval_h()". Is that true? or should I make an empty template?</div>
<div><br></div><div>3) For setting the solver name and the limited-memory mode, Sholud I still use "app->Options()"?i.e., sth like:</div><div> </div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">
app->Options()->SetStringValue("linear_solver", "ma27");<br> app->Options()->SetStringValue("hessian_approximation", "limited-memory");</blockquote><div> </div><div>
4) Out of curiosity, Is there any other examples of using C++ interface using auxiliary data and limited-memory or other options of Ipopt?</div>
<div><br></div><div>5) Is there any sample statistics about the execution time saved using C++ interface? I am currently solving my problem using MalabInterface, and it takes about 30 minutes on a Quad Core with 8GB RAM, I was wondering how much save can I expect if I port the whole thing to C++?</div>
<div><br></div><div>Thanks</div><div>Alireza</div></div>