<div dir="ltr"><div><div><div><div><div><div><div><div>Dear CLP Community,<br><br></div>I've tried to solve a non integer quadratic problem with the CLP API.<br></div>CLP seems to find the optimal solution, but after that, executes a postsolve phase and the objective value is then totally different (and visibly false).<br>
<br></div>Here is as example of output :<br><i>Clp0006I 1984 Obj -4113764.5 Dual inf 57.100756 (236)<br>Clp0006I 2058 Obj -4114185.3<br>Clp0000I Optimal - objective value -4114185.3<br>Coin0511I After Postsolve, objective -182704.15, infeasibilities - dual 0 (0), primal 0 (0)<br>
Clp0032I Optimal objective -182704.1521 - 2058 iterations time 9.752, Presolve 0.02</i><br><br></div>-182704.15 is, according to Cplex the optimal objective value.<br></div>I don't know what <i> </i>-4114185.3 corresponds to.<br>
<br></div>In my code, I use the OsiClpSolverInterface class, read an MPS file, and then call initialSolve() to solve the problem (I stay with the default parameters).<br><br></div>What is the origin of the problem ?<br></div>
Do I need to get rid of the postsolve phase ? To use more specific parameters ?<br><br><div>Thanks in advance for any help you are able to provide !<br><br></div><div>Best regards,<br><br></div>Vincent<br><div><div><div><div>
<div><div><br></div></div></div></div></div></div></div>