[Coin-discuss] Problems with Rounding Heuristic

[Mauro Scarioni]

I've a problem using CbcRounding heuristic.
I've a problem where i need only to find a feasible integer solution, the
obj function is a minor interest.
In this sense i set

(thisModel)->setMaximumNodes(1);

in order to stop the B&B at the first integer solution

In some instances i obtain the following log message:

...................................................
Cbc0015I Node 8556 Obj 0 Unsat 7 depth 22
Cbc0015I Node 8557 Obj 0 Unsat 7 depth 22
Cbc0012I Integer solution of 1e+050 found by heuristic after 184896
iterations and 8557 nodes (68.91 seconds)
Cbc0019I Exiting on maximum solutions
Cbc0005I Partial search - best objective 1e+050 (best possible 0), took
184901 iterations and 8558 nodes (68.91 seconds)
Cbc0006I The LP relaxation is infeasible or too expensive

This solution is not tracked by newSolution method of CbcCompare and is not
usable calling the last solution

But the number of solution find is incremented.

It is possible to define a skip of the heuristic solution finded in this
particular case?

Thank

Mauro

Mauro SCARIONI
IBM Global Business Services
Circonvallazione Idroscalo
20090 Segrate
Telefono 02-5962-5621
Mobile 335-7248615