<div> </div>
<div>Hi Tim,</div>
<div> </div>
<div>I am using an MPS file which is located at the following location:</div>
<div><a onclick="return top.js.OpenExtLink(window,event,this)" href="http://uts.cc.utexas.edu/~jeetv/MIPproblem.mps" target="_blank">http://uts.cc.utexas.edu/~jeetv/MIPproblem.mps</a> (too big to be posted here...) </div>
<div> </div>
<div>when I am using the following code it returns the message isAbandoned regardless </div>
<div>whether branchAndBound() is called or not....but if I use Cbc solver directly, it returns the primal infeasibility. Could you check if the status functions (called in the code below) written OsiCbcSolverInterface() are working properly..
</div>
<div> </div>
<div>regards,</div>
<div>vishy</div>
<div> </div>
<div>#include "flopc.hpp"<br>using namespace flopc;<br>#include "OsiCbcSolverInterface.hpp"</div>
<div>
<p>int main() {<br> MP_model my_knap(new OsiCbcSolverInterface);<br> int num_err = 0;<br> num_err = my_knap->readMps("MIPproblem");<br> if(num_err != 0)<br> cout << "errors reading MPS file\n";
<br> <br> my_knap->branchAndBound();<br>// my_knap.minimize(); // doesn't work and throws segmentation fault; wonder why?</p>
<p>cout << "Num Cols:=" << my_knap->getNumCols()<<endl;<br>cout << "Num Rows:=" << my_knap->getNumRows()<<endl;</p>
<p> if( my_knap->isProvenPrimalInfeasible() == true)<br> cout << "primal infeasible\n";<br> else if( my_knap->isProvenDualInfeasible() == true)<br> cout << "dual infeasible\n";
<br> else if( my_knap->isAbandoned() == true)<br> cout << "isAbandoned\n";<br> else if( my_knap->isProvenOptimal() == true)<br> cout << "isProvenOptimal\n";<br> else if( my_knap->isDualObjectiveLimitReached() == true)
<br> cout << "isDualObjectiveLimitReached\n";<br> else if( my_knap->isPrimalObjectiveLimitReached() == true)<br> cout << "isPrimalObjectiveLimitReached\n";<br> else if( my_knap->isIterationLimitReached() == true)
<br> cout << "isIterationLimitReached\n";<br>}<br></p></div>
<div> </div>
<div> </div>
<div><br><br> </div>
<div><span class="gmail_quote">On 5/10/07, <b class="gmail_sendername">Tim Hultberg</b> <<a onclick="return top.js.OpenExtLink(window,event,this)" href="mailto:Tim.Hultberg@eumetsat.int" target="_blank">Tim.Hultberg@eumetsat.int
</a>> wrote:</span>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">First make sure that the wrong status comes from Cbc by trying<br>instance->isProvenOptimal()<br>Then post the question to the Cbc mailing list.
<br><br>You can also try your model with cplex as solver (i.e not via MPS<br>file)<br>and Cbc on the MPS file...<br><br>Cheers, Tim<br><br>>>> "Vishy Jeet" <<a onclick="return top.js.OpenExtLink(window,event,this)" href="mailto:vishv.jeet@gmail.com" target="_blank">
vishv.jeet@gmail.com </a>> 09/05/2007 18:32 >>><br>Hi Everyone,<br><br>I am running the following little program. My class "dir" has a set of<br>binary variables called "X".<br>After minimization getStatus() return "OPTIMAL" while Xs are displayed
<br>as<br>fractional. When I<br>solve the mipModel.mps using CPLEX: it tells me the problem is<br>infeasible! I<br>don't understand<br>why cbc solver is returning false message OPTIMAL. Any help on this is<br>appreciated.
<br><br>regards,<br>vishy<br><br><br>#include "mathModel.h"<br><br>typedef enum {SUCCESS = 0, FAILURE = -1};<br><br>int main() {<br>int retcode = FAILURE;<br>container c; /* container
<br>class<br>object that will contains all data*/<br>c.readData("c:/dataLocation");<br>dir instance(c); /* Instantiate an<br>object<br>of dir class */<br>instance.minimize();<br>retcode =
instance.getStatus();<br>if (MP_model::OPTIMAL == retcode){<br> instance->writeMps("mipModel", "mps", 1.0);<br> instance.X.display("instance (X)");<br> cout<<"obj val:="<<instance->getObjValue()<<endl;
<br>}<br>return SUCCESS;<br>}// main<br></blockquote></div><br><br clear="all"><br>-- <br>Best Regards,<br>Vishv Jeet, Ph.D.,<br>Operations Research Scientist,<br>Gravitant Inc.,<br>(The Business Governance Company)<br><a onclick="return top.js.OpenExtLink(window,event,this)" href="http://www.gravitant.com/" target="_blank">
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