/** prints vardata to file stream */
void SCIPvardataPrint(
SCIP* scip, /**< SCIP data structure */
SCIP_VARDATA* vardata, /**< variable data */
FILE* file /**< the text file to store the information into */
)
{
SCIP_PROBDATA* probdata;
int* ids;
int i;
probdata = SCIPgetProbData(scip);
assert(probdata != NULL);
ids = SCIPprobdataGetIds(probdata);
assert(ids != NULL);
SCIPinfoMessage(scip, file, "consids = {");
for( i = 0; i < vardata->nconsids; ++i )
{
SCIPinfoMessage(scip, file, "%d->%d", ids[vardata->consids[i]], vardata->consids[i]);
if( i < vardata->nconsids - 1 )
SCIPinfoMessage(scip, file, ",");
}
SCIPinfoMessage(scip, file, "}\n");
}
/** display constraints */
static
void consdataPrint(
SCIP* scip, /**< SCIP data structure */
SCIP_CONSDATA* consdata, /**< constraint data */
FILE* file /**< file stream */
)
{
SCIP_PROBDATA* probdata;
int* ids;
probdata = SCIPgetProbData(scip);
assert(probdata != NULL);
ids = SCIPprobdataGetIds(probdata);
assert(ids != NULL);
SCIPinfoMessage(scip, file, "%s(%d,%d) at node %d\n",
consdata->type == SAME ? "same" : "diff",
ids[consdata->itemid1], ids[consdata->itemid2], SCIPnodeGetNumber(consdata->node) );
}
/** add branching decisions constraints to the sub SCIP */
static
SCIP_RETCODE addBranchingDecisionConss(
SCIP* scip, /**< SCIP data structure */
SCIP* subscip, /**< pricing SCIP data structure */
SCIP_VAR** vars, /**< variable array of the subscuip oder variables */
SCIP_CONSHDLR* conshdlr /**< constraint handler for branching data */
)
{
SCIP_CONS** conss;
SCIP_CONS* cons;
int nconss;
int id1;
int id2;
CONSTYPE type;
SCIP_Real vbdcoef;
SCIP_Real lhs;
SCIP_Real rhs;
int c;
assert( scip != NULL );
assert( subscip != NULL );
assert( conshdlr != NULL );
/* collect all branching decision constraints */
conss = SCIPconshdlrGetConss(conshdlr);
nconss = SCIPconshdlrGetNConss(conshdlr);
/* loop over all branching decision constraints and apply the branching decision if the corresponding constraint is
* active
*/
for( c = 0; c < nconss; ++c )
{
cons = conss[c];
/* ignore constraints which are not active since these are not laying on the current active path of the search
* tree
*/
if( !SCIPconsIsActive(cons) )
continue;
/* collect the two item ids and the branching type (SAME or DIFFER) on which the constraint branched */
id1 = SCIPgetItemid1Samediff(scip, cons);
id2 = SCIPgetItemid2Samediff(scip, cons);
type = SCIPgetTypeSamediff(scip, cons);
SCIPdebugMessage("create varbound for %s(%d,%d)\n", type == SAME ? "same" : "diff",
SCIPprobdataGetIds(SCIPgetProbData(scip))[id1], SCIPprobdataGetIds(SCIPgetProbData(scip))[id2]);
/* depending on the branching type select the correct left and right hand side for the linear constraint which
* enforces this branching decision in the pricing problem MIP
*/
if( type == SAME )
{
lhs = 0.0;
rhs = 0.0;
vbdcoef = -1.0;
}
else if( type == DIFFER )
{
lhs = -SCIPinfinity(scip);
rhs = 1.0;
vbdcoef = 1.0;
}
else
{
SCIPerrorMessage("unknow constraint type <%d>\n, type");
return SCIP_INVALIDDATA;
}
/* add linear (in that case a variable bound) constraint to pricing MIP depending on the branching type:
*
* - branching type SAME: x1 = x2 <=> x1 - x2 = 0 <=> 0 <= x1 - x2 <= 0
*
* - branching type DIFFER: x1 - x2 <= 1 <=> -inf <= x1 - x2 <= 1
*
*/
SCIP_CALL( SCIPcreateConsBasicVarbound(subscip, &cons, SCIPconsGetName(conss[c]),
vars[id1], vars[id2], vbdcoef, lhs, rhs) );
SCIPdebug( SCIPprintCons(subscip, cons, NULL) );
SCIP_CALL( SCIPaddCons(subscip, cons) );
SCIP_CALL( SCIPreleaseCons(subscip, &cons) );
}
return SCIP_OKAY;
}
