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    Hi Simon,<br>

    <br>

    The issue might be that the Hessian matrix that Ipopt considers is

    the Hessian of the original objective function plus the

    ("primal-dual") Hessian of the barrier terms (see Eqn. (11) in the

    Ipopt implementation paper in Math Prog).&nbsp; Even if the first Hessian

    is indefinite, the sum of the two might be positive definite.<br>

    <br>

    It is surprising nevertheless that the algorithm doesn't make good

    progress in the output you provided.&nbsp; First, I suggest you make sure

    that your derivatives are correct (you can use Ipopt's derivative

    checker).&nbsp; Other than that, you might want to see what happens if

    you choose a smaller initial value for the barrier parameter

    (mu_init option).&nbsp; <br>

    <br>

    As for the warm start: In contrast to what the header file for the C

    interface currently says, the warm start should work.&nbsp; Here is the

    updated part of the header file (will be corrected in later Ipopt

    releases):<br>

    <br>

    ------------------------------- 8&lt;

    ------------------------------------------<br>

    <br>

    &nbsp; /** Function calling the Ipopt optimization algorithm for a

    problem<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; previously defined with CreateIpoptProblem.&nbsp; The return<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; specified outcome of the optimization procedure (e.g.,

    success,<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; failure etc).<br>

    &nbsp;&nbsp; */<br>

    &nbsp; IPOPT_EXPORT(enum ApplicationReturnStatus) IpoptSolve(<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp; IpoptProblem ipopt_problem<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; /** Problem that is to be optimized.&nbsp; Ipopt<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; will use the options previously

    specified with<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; AddIpoptOption (etc) for this problem.

    */<br>

    &nbsp;&nbsp;&nbsp; , Number* x&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; /** Input:&nbsp; Starting point<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Output: Optimal solution */<br>

    &nbsp;&nbsp;&nbsp; , Number* g&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; /** Values of constraint at final point<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (output only - ignored if set to NULL)

    */<br>

    &nbsp;&nbsp;&nbsp; , Number* obj_val&nbsp;&nbsp;&nbsp; /** Final value of objective function<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (output only - ignored if set to NULL)

    */<br>

    &nbsp;&nbsp;&nbsp; , Number* mult_g&nbsp;&nbsp;&nbsp;&nbsp; /** Input: Initial values for the

    constraint<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; multipliers (only if warm start

    option<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; is chosen)<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Output: Final multipliers for

    constraints<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (ignored if set to NULL) */<br>

    &nbsp;&nbsp;&nbsp; , Number* mult_x_L&nbsp;&nbsp; /** Input: Initial values for the

    multipliers for<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; lower variable bounds (only if

    warm start<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; option is chosen)<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Output: Final multipliers for lower

    variable<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; bounds (ignored if set to NULL)

    */<br>

    &nbsp;&nbsp;&nbsp; , Number* mult_x_U&nbsp;&nbsp; /** Input: Initial values for the

    multipliers for<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; upper variable bounds (only if

    warm start<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; option is chosen)<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Output: Final multipliers for upper

    variable<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; bounds (ignored if set to NULL)

    */<br>

    &nbsp;&nbsp;&nbsp; , UserDataPtr user_data<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; /** Pointer to user data.&nbsp; This will be<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; passed unmodified to the callback<br>

    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; functions. */<br>

    &nbsp; );<br>

    <br>

    <br>

    ------------------------------- 8&lt;

    ------------------------------------------<br>

    <br>

    But don't expect too much from the warm start - it is difficult to

    warm start interior point methods really effectively...<br>

    <br>

    <br>

    Hope this helps,<br>

    <pre class="moz-signature" cols="72">Andreas Waechter

Associate Professor

Department of Industrial Engineering and Management Sciences

McCormick School of Engineering

Northwestern University

Evanston, IL 60208

USA</pre>

    <br>

    On 02/08/2012 03:44 AM, Altmannshofer, Simon wrote:

    <blockquote

cite="mid:C7A3EFFD8A17524F85F92FDD670E7D7A4198A7E7@BADWLRZ-SWMBX1.ads.mwn.de"

      type="cite">

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      <div class="Section1">

        <p class="MsoNormal"><span lang="EN-US">Hello,<o:p></o:p></span></p>

        <p class="MsoNormal"><span lang="EN-US"><o:p>&nbsp;</o:p></span></p>

        <p class="MsoNormal"><span lang="EN-US">I am using IPOPT to

            solve the NLP arising in Nonlinear Model Predictive Control.

            IPOPT was compiled with MS Visual Studio 10 according to the

            documentation. In order to access IPOPT in MATLAB/Simulink

            the C Interface is used. <o:p></o:p></span></p>

        <p class="MsoNormal"><span lang="EN-US">At the starting point,

            the user-supplied hessian is indefinite (checked with

            MATLAB's chol(hessian)). According to the implementation

            IPOPT should add a multiple of the unity matrix to the

            indefinite hessian. Unfortunately this is not done and the

            objective function is only reduced slightly. See the output

            :<o:p></o:p></span></p>

        <p class="MsoNormal"><span lang="EN-US"><o:p>&nbsp;</o:p></span></p>

        <p class="MsoNormal" style="text-autospace:none"><span

            style="font-size:12.0pt;

            font-family:&quot;Courier New&quot;"><o:p>&nbsp;</o:p></span></p>

        <p class="MsoNormal" style="text-autospace:none"><span

            style="font-size:10.0pt;font-family:&quot;Courier

            New&quot;;color:black" lang="EN-US">List of user-set

            options:</span><span

            style="font-size:12.0pt;font-family:&quot;Courier New&quot;"

            lang="EN-US"><o:p></o:p></span></p>

        <p class="MsoNormal" style="text-autospace:none"><span

            style="font-size:10.0pt;font-family:&quot;Courier

            New&quot;;color:black" lang="EN-US">&nbsp;</span><span

            style="font-size:12.0pt;font-family:&quot;Courier New&quot;"

            lang="EN-US"><o:p></o:p></span></p>

        <p class="MsoNormal" style="text-autospace:none"><span

            style="font-size:10.0pt;font-family:&quot;Courier

            New&quot;;color:black" lang="EN-US">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

            Name&nbsp;&nbsp; Value&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; used</span><span

            style="font-size:12.0pt;

            font-family:&quot;Courier New&quot;" lang="EN-US"><o:p></o:p></span></p>

        <p class="MsoNormal" style="text-autospace:none"><span

            style="font-size:10.0pt;font-family:&quot;Courier

            New&quot;;color:black" lang="EN-US">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

            hessian_approximation = exact&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; yes</span><span

            style="font-size:12.0pt;font-family:&quot;Courier New&quot;"

            lang="EN-US"><o:p></o:p></span></p>

        <p class="MsoNormal" style="text-autospace:none"><span

            style="font-size:10.0pt;font-family:&quot;Courier

            New&quot;;color:black" lang="EN-US">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

            max_iter = 10&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; yes</span><span

            style="font-size:

            12.0pt;font-family:&quot;Courier New&quot;" lang="EN-US"><o:p></o:p></span></p>

        <p class="MsoNormal" style="text-autospace:none"><span

            style="font-size:10.0pt;font-family:&quot;Courier

            New&quot;;color:black" lang="EN-US">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

            output_file = ipopt&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; yes</span><span

            style="font-size:12.0pt;font-family:&quot;Courier New&quot;"

            lang="EN-US"><o:p></o:p></span></p>

        <p class="MsoNormal" style="text-autospace:none"><span

            style="font-size:10.0pt;font-family:&quot;Courier

            New&quot;;color:black" lang="EN-US">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;

            print_user_options = yes&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; yes</span><span

            style="font-size:12.0pt;font-family:&quot;Courier New&quot;"

            lang="EN-US"><o:p></o:p></span></p>

        <p class="MsoNormal" style="text-autospace:none"><span

            style="font-size:10.0pt;font-family:&quot;Courier

            New&quot;;color:black" lang="EN-US">&nbsp;</span><span

            style="font-size:12.0pt;font-family:&quot;Courier New&quot;"

            lang="EN-US"><o:p></o:p></span></p>

        <p class="MsoNormal" style="text-autospace:none"><span

            style="font-size:10.0pt;font-family:&quot;Courier

            New&quot;;color:black" lang="EN-US">******************************************************************************</span><span

            style="font-size:12.0pt;font-family:&quot;Courier New&quot;"

            lang="EN-US"><o:p></o:p></span></p>

        <p class="MsoNormal" style="text-autospace:none"><span

            style="font-size:10.0pt;font-family:&quot;Courier

            New&quot;;color:black" lang="EN-US">This program contains

            Ipopt, a library for large-scale nonlinear optimization.</span><span

            style="font-size:12.0pt;font-family:&quot;Courier New&quot;"

            lang="EN-US"><o:p></o:p></span></p>

        <p class="MsoNormal" style="text-autospace:none"><span

            style="font-size:10.0pt;font-family:&quot;Courier

            New&quot;;color:black" lang="EN-US">&nbsp;Ipopt is released as

            open source code under the Eclipse Public License (EPL).</span><span

            style="font-size:12.0pt;font-family:&quot;Courier New&quot;"

            lang="EN-US"><o:p></o:p></span></p>

        <p class="MsoNormal" style="text-autospace:none"><span

            style="font-size:10.0pt;font-family:&quot;Courier

            New&quot;;color:black" lang="EN-US">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; For more

            information visit <a class="moz-txt-link-freetext" href="http://projects.coin-or.org/Ipopt">http://projects.coin-or.org/Ipopt</a></span><span

            style="font-size:12.0pt;font-family:&quot;Courier New&quot;"

            lang="EN-US"><o:p></o:p></span></p>

        <p class="MsoNormal" style="text-autospace:none"><span

            style="font-size:10.0pt;font-family:&quot;Courier

            New&quot;;color:black" lang="EN-US">******************************************************************************</span><span

            style="font-size:12.0pt;font-family:&quot;Courier New&quot;"

            lang="EN-US"><o:p></o:p></span></p>

        <p class="MsoNormal" style="text-autospace:none"><span

            style="font-size:10.0pt;font-family:&quot;Courier

            New&quot;;color:black" lang="EN-US">&nbsp;</span><span

            style="font-size:12.0pt;font-family:&quot;Courier New&quot;"

            lang="EN-US"><o:p></o:p></span></p>

      </div>

    </blockquote>

    [.... Message was getting too long ....]<br>

    <blockquote

cite="mid:C7A3EFFD8A17524F85F92FDD670E7D7A4198A7E7@BADWLRZ-SWMBX1.ads.mwn.de"

      type="cite">

      <div class="Section1"><o:p></o:p>

        <p class="MsoNormal"><o:p>&nbsp;</o:p></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas">My questions

            are:<o:p></o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas" lang="EN-US">1)

            Why does IPOPT not recognize the indefinite hessian matrix?

            What possible options might clear this problem? With the

            BFGS formula for the hessian everything works fine. But we

            want to use the exact hessian.<o:p></o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas" lang="EN-US"><o:p>&nbsp;</o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas" lang="EN-US">2)

            Does the warm start option also work with the C Interface?<o:p></o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas" lang="EN-US"><o:p>&nbsp;</o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas" lang="EN-US">Best

            Regards

            <o:p></o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas" lang="EN-US">Simon</span><span

            style="font-size:10.5pt;font-family:Consolas"><o:p></o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas"><o:p>&nbsp;</o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas">-----------------------------------------------------<o:p></o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas">Dipl.-Ing.

            Simon Altmannshofer<o:p></o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas">Lehrstuhl f&uuml;r

            Regelungstechnik<o:p></o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas">Technische

            Universit&auml;t M&uuml;nchen<o:p></o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas">Boltzmannstra&szlig;e

            15<o:p></o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas">85748 Garching

            bei M&uuml;nchen<o:p></o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas"><o:p>&nbsp;</o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas">Tel.:&nbsp;&nbsp;&nbsp;&nbsp; +49

            (89) 289-15679<o:p></o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas">Fax:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; +49

            (89) 289-15653<o:p></o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas">E-Mail:&nbsp;&nbsp;

            <a moz-do-not-send="true"

              href="mailto:tobias.kloiber@tum.de">simon.altmannshofer@tum.de</a><o:p></o:p></span></p>

        <p class="MsoNormal"><span

            style="font-size:10.5pt;font-family:Consolas">Internet:

            <a moz-do-not-send="true" href="http://www.rt.mw.tum.de">www.rt.mw.tum.de</a><o:p></o:p></span></p>

        <p class="MsoNormal"><o:p>&nbsp;</o:p></p>

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      <pre wrap="">_______________________________________________

Ipopt mailing list

<a class="moz-txt-link-abbreviated" href="mailto:Ipopt@list.coin-or.org">Ipopt@list.coin-or.org</a>

<a class="moz-txt-link-freetext" href="http://list.coin-or.org/mailman/listinfo/ipopt">http://list.coin-or.org/mailman/listinfo/ipopt</a>

</pre>

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