/** branching execution method for not completely fixed pseudo solutions */
static
SCIP_DECL_BRANCHEXECPS(branchExecpsRandom)
{ /*lint --e{715}*/
SCIP_BRANCHRULEDATA* branchruledata;
SCIP_VAR** pseudocands;
int npseudocands;
int bestcand;
assert(branchrule != NULL);
assert(strcmp(SCIPbranchruleGetName(branchrule), BRANCHRULE_NAME) == 0);
assert(scip != NULL);
assert(result != NULL);
SCIPdebugMessage("Execps method of random branching\n");
branchruledata = SCIPbranchruleGetData(branchrule);
assert(branchruledata != NULL);
/* get branching candidates */
SCIP_CALL( SCIPgetPseudoBranchCands(scip, &pseudocands, NULL, &npseudocands) );
assert(npseudocands > 0);
/* get random branching candidate */
bestcand = SCIPgetRandomInt(0, npseudocands-1, &branchruledata->seed);
assert(bestcand >= 0);
SCIPdebugMessage(" -> %d candidates, selected candidate %d: variable <%s>\n",
npseudocands, bestcand, SCIPvarGetName(pseudocands[bestcand]));
/* perform the branching */
SCIP_CALL( SCIPbranchVar(scip, pseudocands[bestcand], NULL, NULL, NULL) );
*result = SCIP_BRANCHED;
return SCIP_OKAY;
}
/** branching execution method for fractional LP solutions */
static
SCIP_DECL_BRANCHEXECLP(branchExeclpLeastinf)
{ /*lint --e{715}*/
SCIP_VAR** lpcands;
SCIP_Real* lpcandsfrac;
int nlpcands;
SCIP_Real infeasibility;
SCIP_Real score;
SCIP_Real obj;
SCIP_Real bestscore;
SCIP_Real bestobj;
int bestcand;
int i;
assert(branchrule != NULL);
assert(strcmp(SCIPbranchruleGetName(branchrule), BRANCHRULE_NAME) == 0);
assert(scip != NULL);
assert(result != NULL);
SCIPdebugMessage("Execlp method of leastinf branching\n");
/* get branching candidates */
SCIP_CALL( SCIPgetLPBranchCands(scip, &lpcands, NULL, &lpcandsfrac, NULL, &nlpcands, NULL) );
assert(nlpcands > 0);
/* search the least infeasible candidate */
bestscore = SCIP_REAL_MIN;
bestobj = 0.0;
bestcand = -1;
for( i = 0; i < nlpcands; ++i )
{
assert(lpcands[i] != NULL);
infeasibility = lpcandsfrac[i];
infeasibility = MIN(infeasibility, 1.0-infeasibility);
score = 1.0 - infeasibility;
score *= SCIPvarGetBranchFactor(lpcands[i]);
obj = SCIPvarGetObj(lpcands[i]);
obj = REALABS(obj);
if( SCIPisGT(scip, score, bestscore)
|| (SCIPisGE(scip, score, bestscore) && obj > bestobj) )
{
bestscore = score;
bestobj = obj;
bestcand = i;
}
}
assert(bestcand >= 0);
SCIPdebugMessage(" -> %d candidates, selected candidate %d: variable <%s> (frac=%g, obj=%g, factor=%g, score=%g)\n",
nlpcands, bestcand, SCIPvarGetName(lpcands[bestcand]), lpcandsfrac[bestcand], bestobj,
SCIPvarGetBranchFactor(lpcands[bestcand]), bestscore);
/* perform the branching */
SCIP_CALL( SCIPbranchVar(scip, lpcands[bestcand], NULL, NULL, NULL) );
*result = SCIP_BRANCHED;
return SCIP_OKAY;
}
/** branching execution method for fractional LP solutions */
static
SCIP_DECL_BRANCHEXECLP(branchExeclpPscost)
{ /*lint --e{715}*/
SCIP_VAR** lpcands;
SCIP_Real* lpcandssol;
SCIP_Real bestscore;
SCIP_Real bestrootdiff;
int nlpcands;
int bestcand;
int c;
assert(branchrule != NULL);
assert(strcmp(SCIPbranchruleGetName(branchrule), BRANCHRULE_NAME) == 0);
assert(scip != NULL);
assert(result != NULL);
SCIPdebugMessage("Execlp method of pscost branching\n");
/* get branching candidates */
SCIP_CALL( SCIPgetLPBranchCands(scip, &lpcands, &lpcandssol, NULL, NULL, &nlpcands, NULL) );
assert(nlpcands > 0);
bestcand = -1;
bestscore = -SCIPinfinity(scip);
bestrootdiff = 0.0;
for( c = 0; c < nlpcands; ++c )
{
SCIP_Real score;
SCIP_Real rootsolval;
SCIP_Real rootdiff;
score = SCIPgetVarPseudocostScore(scip, lpcands[c], lpcandssol[c]);
rootsolval = SCIPvarGetRootSol(lpcands[c]);
rootdiff = REALABS(lpcandssol[c] - rootsolval);
if( SCIPisSumGT(scip, score, bestscore) || (SCIPisSumEQ(scip, score, bestscore) && rootdiff > bestrootdiff) )
{
bestcand = c;
bestscore = score;
bestrootdiff = rootdiff;
}
}
assert(0 <= bestcand && bestcand < nlpcands);
assert(!SCIPisFeasIntegral(scip, lpcandssol[bestcand]));
/* perform the branching */
SCIPdebugMessage(" -> %d cands, selected cand %d: variable <%s> (solval=%g, score=%g)\n",
nlpcands, bestcand, SCIPvarGetName(lpcands[bestcand]), lpcandssol[bestcand], bestscore);
/* perform the branching */
SCIP_CALL( SCIPbranchVar(scip, lpcands[bestcand], NULL, NULL, NULL) );
*result = SCIP_BRANCHED;
return SCIP_OKAY;
}
/** selects a variable out of the given candidate array and performs the branching */
static
SCIP_RETCODE performBranching(
SCIP* scip, /**< SCIP data structure */
SCIP_VAR** cands, /**< candidate array */
SCIP_Real* candsols, /**< array of candidate solution values, or NULL */
int ncands, /**< number of candidates */
SCIP_Real conflictweight, /**< weight in score calculations for conflict score */
SCIP_Real inferenceweight, /**< weight in score calculations for inference score */
SCIP_Real cutoffweight, /**< weight in score calculations for cutoff score */
SCIP_Real reliablescore, /**< score which is seen to be reliable for a branching decision */
SCIP_Bool useweightedsum, /**< should a weighted sum of inference, conflict and cutoff weights be used? */
SCIP_RESULT* result /**< buffer to store result (branched, reduced domain, ...) */
)
{
SCIP_VAR* bestaggrcand;
SCIP_VAR* bestvaluecand;
SCIP_Real bestval;
SCIP_Real bestaggrscore;
SCIP_Real bestvaluescore;
SCIP_Real bestbranchpoint;
SCIP_BRANCHDIR bestbranchdir;
SCIP_NODE* downchild;
SCIP_NODE* eqchild;
SCIP_NODE* upchild;
bestbranchpoint = SCIP_UNKNOWN;
bestbranchdir = SCIP_BRANCHDIR_DOWNWARDS;
bestvaluescore = 0.0;
bestvaluecand = NULL;
assert(ncands > 0);
assert(result != NULL);
*result = SCIP_DIDNOTFIND;
/* check if the weighted sum between the average inferences and conflict score should be used */
if( useweightedsum )
{
int c;
bestaggrcand = cands[0];
bestvaluecand = cands[0];
assert(cands[0] != NULL);
if( candsols == NULL )
{
bestval = SCIP_UNKNOWN;
/* get domain value score for the first candidate */
bestvaluescore = getValueScore(scip, cands[0], conflictweight, cutoffweight, reliablescore, &bestbranchpoint, &bestbranchdir);
SCIPdebugMessage("current best value candidate <%s>[%g,%g] %s <%g> (value %g)\n",
SCIPvarGetName(bestvaluecand), SCIPvarGetLbLocal(bestvaluecand), SCIPvarGetUbLocal(bestvaluecand),
bestbranchdir == SCIP_BRANCHDIR_DOWNWARDS ? "<=" : ">=", bestbranchpoint, bestvaluescore);
}
else
bestval = candsols[0];
/* get aggregated score for the first candidate */
bestaggrscore = getAggrScore(scip, cands[0], conflictweight, inferenceweight, cutoffweight, reliablescore);
for( c = 1; c < ncands; ++c )
{
SCIP_VAR* cand;
SCIP_Real val;
SCIP_Real aggrscore;
SCIP_Real branchpoint;
SCIP_BRANCHDIR branchdir;
cand = cands[c];
assert(cand != NULL);
if( candsols == NULL )
{
SCIP_Real valuescore;
val = SCIP_UNKNOWN;
/* get domain value score for the candidate */
valuescore = getValueScore(scip, cand, conflictweight, cutoffweight, reliablescore, &branchpoint, &branchdir);
/* evaluate the candidate against the currently best candidate w.r.t. domain value score */
evaluateValueCand(cand, valuescore, branchpoint, branchdir, &bestvaluecand, &bestvaluescore, &bestbranchpoint, &bestbranchdir);
SCIPdebugMessage("current best value candidate <%s>[%g,%g] %s <%g> (value %g)\n",
SCIPvarGetName(bestvaluecand), SCIPvarGetLbLocal(bestvaluecand), SCIPvarGetUbLocal(bestvaluecand),
bestbranchdir == SCIP_BRANCHDIR_DOWNWARDS ? "<=" : ">=", bestbranchpoint, bestvaluescore);
}
else
val = candsols[c];
/* get aggregated score for the candidate */
aggrscore = getAggrScore(scip, cand, conflictweight, inferenceweight, cutoffweight, reliablescore);
SCIPdebugMessage(" -> cand <%s>: prio=%d, solval=%g, score=%g\n", SCIPvarGetName(cand), SCIPvarGetBranchPriority(cand),
val == SCIP_UNKNOWN ? SCIPgetVarSol(scip, cand) : val, aggrscore); /*lint !e777*/
/* evaluate the candidate against the currently best candidate w.r.t. aggregated score */
evaluateAggrCand(cand, aggrscore, val, &bestaggrcand, &bestaggrscore, &bestval);
}
}
else
{
int c;
bestaggrcand = cands[0];
assert(cands[0] != NULL);
if( candsols != NULL )
bestval = candsols[0];
else
bestval = SCIP_UNKNOWN;
bestaggrscore = SCIPgetVarAvgInferenceScore(scip, cands[0]);
/* search for variable with best score w.r.t. average inferences per branching */
for( c = 1; c < ncands; ++c )
{
SCIP_VAR* cand;
SCIP_Real val;
SCIP_Real aggrscore;
cand = cands[c];
assert(cand != NULL);
if( candsols != NULL )
val = candsols[c];
else
val = SCIP_UNKNOWN;
aggrscore = SCIPgetVarAvgInferenceScore(scip, cand);
/* in case the average inferences score is below the reliable score we set it to zero since it is seen to be
* unreliable
*/
if( aggrscore < reliablescore )
aggrscore = 0.0;
SCIPdebugMessage(" -> cand <%s>: prio=%d, solval=%g, score=%g\n", SCIPvarGetName(cand), SCIPvarGetBranchPriority(cand),
val == SCIP_UNKNOWN ? SCIPgetVarSol(scip, cand) : val, aggrscore); /*lint !e777*/
/* evaluate the candidate against the currently best candidate */
evaluateAggrCand(cand, aggrscore, val, &bestaggrcand, &bestaggrscore, &bestval);
}
}
assert(bestaggrcand != NULL);
SCIPdebugMessage(" -> %d candidates, selected variable <%s>[%g,%g] (prio=%d, solval=%.12f, score=%g, conflict=%g cutoff=%g, inference=%g)\n",
ncands, SCIPvarGetName(bestaggrcand), SCIPvarGetLbLocal (bestaggrcand), SCIPvarGetUbLocal(bestaggrcand), SCIPvarGetBranchPriority(bestaggrcand),
bestval == SCIP_UNKNOWN ? SCIPgetVarSol(scip, bestaggrcand) : bestval, bestaggrscore, /*lint !e777*/
SCIPgetVarConflictScore(scip, bestaggrcand), SCIPgetVarAvgInferenceCutoffScore(scip, bestaggrcand, cutoffweight),
SCIPgetVarAvgInferenceScore(scip, bestaggrcand));
/* perform the branching */
if( candsols != NULL )
{
SCIP_CALL( SCIPbranchVarVal(scip, bestaggrcand, SCIPgetBranchingPoint(scip, bestaggrcand, bestval), &downchild, &eqchild, &upchild) );
}
else if( bestbranchpoint == SCIP_UNKNOWN ) /*lint !e777*/
{
SCIP_CALL( SCIPbranchVar(scip, bestaggrcand, &downchild, &eqchild, &upchild) );
}
else
{
SCIP_Real estimate;
SCIP_Real downprio;
SCIP_Real upprio;
SCIP_Real downub;
SCIP_Real uplb;
assert(bestvaluecand != NULL);
downprio = 0.0;
upprio = 0.0;
if( bestbranchdir == SCIP_BRANCHDIR_DOWNWARDS )
{
downprio = 1.0;
downub = bestbranchpoint;
uplb = bestbranchpoint + 1.0;
}
else
{
upprio = 1.0;
downub = bestbranchpoint - 1.0;
uplb = bestbranchpoint;
}
/* calculate the child estimate */
estimate = SCIPcalcChildEstimate(scip, bestvaluecand, downub);
/* create down child */
SCIP_CALL( SCIPcreateChild(scip, &downchild, downprio, estimate) );
/* change upper bound in down child */
SCIP_CALL( SCIPchgVarUbNode(scip, downchild, bestvaluecand, downub) );
/* calculate the child estimate */
estimate = SCIPcalcChildEstimate(scip, bestvaluecand, uplb);
/* create up child */
SCIP_CALL( SCIPcreateChild(scip, &upchild, upprio, estimate) );
/* change lower bound in up child */
SCIP_CALL( SCIPchgVarLbNode(scip, upchild, bestvaluecand, uplb) );
SCIPdebugMessage("branch on variable <%s> and value <%g>\n", SCIPvarGetName(bestvaluecand), bestbranchpoint);
eqchild = NULL;
}
if( downchild != NULL || eqchild != NULL || upchild != NULL )
{
*result = SCIP_BRANCHED;
}
else
{
/* if there are no children, then variable should have been fixed by SCIPbranchVar(Val) */
assert(SCIPisEQ(scip, SCIPvarGetLbLocal(bestaggrcand), SCIPvarGetUbLocal(bestaggrcand)));
*result = SCIP_REDUCEDDOM;
}
return SCIP_OKAY;
}
static
SCIP_DECL_BRANCHEXECPS(branchExecpsMyfullstrong)
{ /*lint --e{715}*/
SCIP_PROBDATA* probdata;
SCIP_VAR** cands;
int ncands;
SCIP_NODE* childnode_0; /* z_j = 0 */
SCIP_NODE* childnode_1; /* z_j = 1 */
/* probdata */
int p;
int ndep;
SCIP_VAR** var_z; /* [p] 01 variables */
/* "_" means the matrix for blas */
SCIP_Real* orig_Q_; /* [p*p] <- (X^t) X */
SCIP_Real* orig_q; /* [p] <- (X^t) y */
SCIP_Real r;
int* Mdep; /* [ndep] */
int* groupX; /* [ndep*p] */
int dim;
SCIP_Real RSS; /* residual sum of square */
SCIP_Real RSS_new;
SCIP_Real* a; /* [dim] */
int ublb;
int *Branchz; /* [3*p] */
int *Branchz_new; /* [3*p] */
SCIP_Real* Q_; /* sub matrix of orig_Q_ */
SCIP_Real* Xy; /* sub vector of orig_q */
int* list; /* list of candidate variables */
int i,j,t,memo,ct;
int ind;
int dpv;
#if MYPARA_LOG
printf("[myfullstrong brnaching]");
Longline();
#endif
/* get branching rule data */
/*
SCIP_BRANCHRULEDATA* branchruledata;
branchruledata = SCIPbranchruleGetData(branchrule);
assert(branchruledata != NULL);
*/
/* get problem data*/
probdata = SCIPgetProbData(scip);
assert(probdata != NULL);
p = SCIPprobdataGetNexvars(probdata);
ndep = SCIPprobdataGetNdep(probdata);
orig_Q_ = SCIPprobdataGetQ(probdata);
orig_q = SCIPprobdataGetq(probdata);
r = SCIPprobdataGetr(probdata);
var_z = SCIPprobdataGetVars_z(probdata);
if( ndep ){
Mdep = SCIPprobdataGetMdep(probdata);
groupX = SCIPprobdataGetgroupX(probdata);
}else{
Mdep = NULL;
groupX = NULL;
}
/* alloc */
SCIP_CALL( SCIPallocBufferArray(scip, &list, p));
SCIP_CALL( SCIPallocBufferArray(scip, &Branchz, 3*p));
SCIP_CALL( SCIPallocBufferArray(scip, &Branchz_new, 3*p));
GenerateZeroVecInt( p, list);
GenerateZeroVecInt( 3*p, Branchz);
/* get pseudo candidates (non-fixed integer variables) */
SCIP_CALL( SCIPgetPseudoBranchCands(scip, &cands, NULL, &ncands) );
for(i=0; i<ncands; i++){
for(j=0; j<p; j++){
if( cands[i]==var_z[j] ){
list[j] = 1;
break;
}
}
}
#if MYPARA_LOG
printf("list:");
printintv( p, list);
#endif
/* get branching info */
for(i=0; i<p; ++i){
ublb = SCIPround(scip, SCIPcomputeVarUbLocal(scip, var_z[i])
+ SCIPcomputeVarLbLocal(scip, var_z[i]));
*(Branchz+(ublb*p)+i) = 1;
}
#if MYPARA_LOG
for(i=0; i<3; i++){
for(j=0; j<p; j++){
printf("%d, ", *(Branchz+(i*p)+j));
}
newline();
}
#endif
RSS = -1.0;
ind = -1;
for(i=0; i<p; i++){
/* copy */
for(j=0; j<(3*p); j++){
Branchz_new[j] = Branchz[j];
}
/*
* solve
* Q a = Xy
*/
if( list[i] == 1 ){
Branchz_new[i] = 1;
Branchz_new[p+i] = 0;
if( ndep ){
for(t=0; t<ndep; t++){
memo = -1;
for(j=0; j<p; j++){
if( *(groupX+(t*p)+j)==1 ){
if( Branchz_new[j]==1 ) break;
if( Branchz_new[p+j]==1 ) memo=j;
if( j==Mdep[t] ){
if( memo==-1 ){
printf("error in branch_myfullstrong.c\n");
stop();
}
*(Branchz_new+p+memo) = 0;
*(Branchz_new+memo) = 1;
break;
}
}
}
}
}
dim = p - sumint( &Branchz_new[0], p);
/* alloc */
SCIP_CALL( SCIPallocBufferArray( scip, &a, dim));
SCIP_CALL( SCIPallocBufferArray( scip, &Q_, dim*dim));
SCIP_CALL( SCIPallocBufferArray( scip, &Xy, dim));
/* generate Q and Xy */
/* Q */
ct = 0;
for(j=0; j<p; j++){
if( (Branchz_new[j]==0) && (j != i) ){
for(t=0; t<p; t++){
if( (Branchz_new[t]==0) && (t != i ) ){
Q_[ct++] = mat_( orig_Q_, p, j, t);
}
}
}
}
if( ct != (dim*dim) ){
printf("error in branch_myfullstrong.c\n");
stop();
}
/* Xy */
ct = 0;
for(j=0; j<p; j++){
if( (Branchz_new[j]==0) && (j != i) ){
Xy[ct++] = orig_q[j];
}
}
if( ct != dim ){
printf("error in branch_myfullstrong.c\n");
stop();
}
dpv = _dposv_( Q_, Xy, dim, a);
if( dpv == 0 ){
/* test */
RSS_new = RSSvalue( dim, a, Xy, r);
if( RSS_new > RSS ){
RSS = RSS_new;
ind = i;
}
#if MYPARA_LOG
printf("%d: RSS = %f\n", i, RSS_new);
#endif
}
/* free */
SCIPfreeBufferArray(scip, &Q_);
SCIPfreeBufferArray(scip, &Xy);
SCIPfreeBufferArray(scip, &a);
}
}
#if MYPARA_LOG
printf("max->%dth var. \n", ind);
#endif
if( ind == -1 ){
/* free */
SCIPfreeBufferArray(scip, &list);
SCIPfreeBufferArray(scip, &Branchz);
SCIPfreeBufferArray(scip, &Branchz_new);
*result = SCIP_DIDNOTRUN;
return SCIP_OKAY;
}
SCIP_CALL( SCIPbranchVar( scip, var_z[ind], &childnode_0, NULL, &childnode_1));
/* free */
SCIPfreeBufferArray(scip, &list);
SCIPfreeBufferArray(scip, &Branchz);
SCIPfreeBufferArray(scip, &Branchz_new);
*result = SCIP_BRANCHED;
return SCIP_OKAY;
}
