int SCIPSolver::solve(){
DBG("solve!%s\n", "");
if(!has_been_added) initialise();
if(_verbosity > 0 && _verbosity < 3){
// Do nothing extra
} else if(_verbosity >= 3){
SCIP_CALL_EXC(SCIPprintOrigProblem(_scip, NULL, NULL, FALSE));
// SCIP_CALL_EXC(SCIPwriteOrigProblem(_scip, "scip.lp", "lp", TRUE));
} else {
// disable scip output to stdout
SCIP_CALL_EXC( SCIPsetMessagehdlr(_scip, NULL) );
}
SCIP_CALL_EXC( SCIPsolve(_scip) );
SCIP_STATUS status = SCIPgetStatus(_scip);
if( status == SCIP_STATUS_OPTIMAL ) return SAT;
else if( status == SCIP_STATUS_INFEASIBLE ) return UNSAT;
else return UNKNOWN;
}
SCIP_RETCODE GamsScip::setupSCIP()
{
/*
#ifdef COIN_HAS_OSICPX
// change default LP solver to CPLEX, if license available
if( gmo != NULL && checkCplexLicense(gmo, pal) )
{
SCIP_CALL( SCIPlpiSwitchSetSolver(SCIP_LPISW_CPLEX) );
}
#endif
*/
if( scip == NULL )
{
// if called first time, create a new SCIP instance and include all plugins that we need and setup interface parameters
SCIP_MESSAGEHDLR* messagehdlr;
SCIP_NLPI* nlpiipopt;
SCIP_CALL( SCIPcreate(&scip) );
// create and install our message handler
SCIP_CALL( SCIPmessagehdlrCreate(&messagehdlr, FALSE, NULL, FALSE,
GamsScipPrintLogStat, GamsScipPrintLog, GamsScipPrintLog, NULL,
(SCIP_MESSAGEHDLRDATA*)gev) );
SCIP_CALL( SCIPsetMessagehdlr(scip, messagehdlr) );
SCIP_CALL( SCIPmessagehdlrRelease(&messagehdlr) );
SCIP_CALL( SCIPincludeDefaultPlugins(scip) );
SCIP_CALL( SCIPincludeReaderGmo(scip) );
SCIP_CALL( SCIPincludeEventHdlrSolveTrace(scip, gmo) );
/* SCIP_CALL( SCIPincludePropDefaultBounds(scip) ); */
if( ipoptlicensed )
{
nlpiipopt = SCIPfindNlpi(scip, "ipopt");
if( nlpiipopt != NULL )
{
SCIPsetModifiedDefaultSettingsIpopt(nlpiipopt, "linear_solver ma27\nlinear_system_scaling mc19\n");
SCIP_CALL( SCIPincludeExternalCodeInformation(scip, "HSL MA27 and MC19", "Harwell Subroutine Libraries (www.hsl.rl.ac.uk) from commercially supported Ipopt") );
}
}
/*
else
{
nlpiipopt = SCIPfindNlpi(scip, "ipopt");
if( nlpiipopt != NULL )
{
SCIPsetModifiedDefaultSettingsIpopt(nlpiipopt, "linear_solver mumps\n");
}
}
*/
/* SCIP_CALL( SCIPaddBoolParam(scip, "gams/solvefinal",
* "whether the problem should be solved with fixed discrete variables to get dual values",
* NULL, FALSE, TRUE, NULL, NULL) );
*/
SCIP_CALL( SCIPaddBoolParam(scip, "display/statistics",
"whether to print statistics on a solve",
NULL, FALSE, FALSE, NULL, NULL) );
SCIP_CALL( SCIPaddStringParam(scip, "gams/interactive",
"command to be issued to the SCIP shell instead of issuing a solve command",
NULL, FALSE, "", NULL, NULL) );
#if 0
SCIP_CALL( SCIPaddStringParam(scip, "constraints/attrfile",
"name of file that specifies constraint attributes",
NULL, FALSE, "", NULL, NULL) );
#endif
/*
SCIP_CALL( SCIPaddStringParam(scip, "lp/solver",
"LP solver to use (clp, cplex, mosek, soplex, gurobi, xpress)",
NULL, FALSE, SCIP_LPISW_SOLVERNAMES[SCIPlpiSwitchGetCurrentSolver()], GamsScipParamChgdLpSolver, NULL) );
*/
}
else
{
// if called before, only clear up problem and reset parameters
SCIP_CALL( SCIPfreeProb(scip) );
SCIP_CALL( SCIPresetParams(scip) );
}
/** pass current GMO into GMO reader, so it does not read instance from file */
SCIPsetGMOReaderGmo(scip, gmo);
return SCIP_OKAY;
}