static enum order_sign interval_minmax(Polyhedron *I)
{
int i;
int min = 1;
int max = -1;
assert(I->Dimension == 1);
POL_ENSURE_VERTICES(I);
for (i = 0; i < I->NbRays; ++i) {
if (value_pos_p(I->Ray[i][1]))
max = 1;
else if (value_neg_p(I->Ray[i][1]))
min = -1;
else {
if (max < 0)
max = 0;
if (min > 0)
min = 0;
}
}
if (min > 0)
return order_gt;
if (max < 0)
return order_lt;
if (min == max)
return order_eq;
if (max == 0)
return order_le;
if (min == 0)
return order_ge;
return order_unknown;
}
/*---------------------------------------------------------------------*/
static int exist_points(int pos,Polyhedron *Pol,Value *context) {
Value LB, UB, k,tmp;
value_init(LB); value_init(UB);
value_init(k); value_init(tmp);
value_set_si(LB,0);
value_set_si(UB,0);
/* Problem if UB or LB is INFINITY */
if (lower_upper_bounds(pos,Pol,context,&LB,&UB) !=0) {
errormsg1("exist_points", "infdom", "infinite domain");
value_clear(LB);
value_clear(UB);
value_clear(k);
value_clear(tmp);
return -1;
}
value_set_si(context[pos],0);
if(value_lt(UB,LB)) {
value_clear(LB);
value_clear(UB);
value_clear(k);
value_clear(tmp);
return 0;
}
if (!Pol->next) {
value_subtract(tmp,UB,LB);
value_increment(tmp,tmp);
value_clear(UB);
value_clear(LB);
value_clear(k);
return (value_pos_p(tmp));
}
for (value_assign(k,LB);value_le(k,UB);value_increment(k,k)) {
/* insert k in context */
value_assign(context[pos],k);
if (exist_points(pos+1,Pol->next,context) > 0 ) {
value_clear(LB); value_clear(UB);
value_clear(k); value_clear(tmp);
return 1;
}
}
/* Reset context */
value_set_si(context[pos],0);
value_clear(UB); value_clear(LB);
value_clear(k); value_clear(tmp);
return 0;
}
enum lp_result PL_polyhedron_opt(Polyhedron *P, Value *obj, Value denom,
enum lp_dir dir, Value *opt)
{
int i;
int first = 1;
Value val, d;
enum lp_result res = lp_empty;
POL_ENSURE_VERTICES(P);
if (emptyQ(P))
return res;
value_init(val);
value_init(d);
for (i = 0; i < P->NbRays; ++ i) {
Inner_Product(P->Ray[i]+1, obj, P->Dimension+1, &val);
if (value_zero_p(P->Ray[i][0]) && value_notzero_p(val)) {
res = lp_unbounded;
break;
}
if (value_zero_p(P->Ray[i][1+P->Dimension])) {
if ((dir == lp_min && value_neg_p(val)) ||
(dir == lp_max && value_pos_p(val))) {
res = lp_unbounded;
break;
}
} else {
res = lp_ok;
value_multiply(d, denom, P->Ray[i][1+P->Dimension]);
if (dir == lp_min)
mpz_cdiv_q(val, val, d);
else
mpz_fdiv_q(val, val, d);
if (first || (dir == lp_min ? value_lt(val, *opt) :
value_gt(val, *opt)))
value_assign(*opt, val);
first = 0;
}
}
value_clear(d);
value_clear(val);
return res;
}
/* INDEX = 1 .... Dimension */
int PolyhedronLTQ (Polyhedron *Pol1,Polyhedron *Pol2,int INDEX, int PDIM, int NbMaxConstrs) {
int res, dim, i, j, k;
Polyhedron *Q1, *Q2, *Q3, *Q4, *Q;
Matrix *Mat;
if (Pol1->next || Pol2->next) {
errormsg1("PolyhedronLTQ", "compoly", "Can only compare polyhedra");
return 0;
}
if (Pol1->Dimension != Pol2->Dimension) {
errormsg1("PolyhedronLTQ","diffdim","Polyhedra are not same dimension");
return 0;
}
dim = Pol1->Dimension+2;
POL_ENSURE_FACETS(Pol1);
POL_ENSURE_VERTICES(Pol1);
POL_ENSURE_FACETS(Pol2);
POL_ENSURE_VERTICES(Pol2);
#ifdef DEBUG
fprintf(stdout, "P1\n");
Polyhedron_Print(stdout,P_VALUE_FMT,Pol1);
fprintf(stdout, "P2\n");
Polyhedron_Print(stdout,P_VALUE_FMT,Pol2);
#endif
/* Create the Line to add */
k = Pol1->Dimension-INDEX+1-PDIM;
Mat = Matrix_Alloc(k,dim);
Vector_Set(Mat->p_Init,0,dim*k);
for(j=0,i=INDEX;j<k;i++,j++)
value_set_si(Mat->p[j][i],1);
Q1 = AddRays(Mat->p[0],k,Pol1,NbMaxConstrs);
Q2 = AddRays(Mat->p[0],k,Pol2,NbMaxConstrs);
#ifdef DEBUG
fprintf(stdout, "Q1\n");
Polyhedron_Print(stdout,P_VALUE_FMT,Q1);
fprintf(stdout, "Q2\n");
Polyhedron_Print(stdout,P_VALUE_FMT,Q2);
#endif
Matrix_Free(Mat);
Q = DomainIntersection(Q1,Q2,NbMaxConstrs);
#ifdef DEBUG
fprintf(stdout, "Q\n");
Polyhedron_Print(stdout,P_VALUE_FMT,Q);
#endif
Domain_Free(Q1);
Domain_Free(Q2);
if (emptyQ(Q)) res = 0; /* not comparable */
else {
Q1 = DomainIntersection(Pol1,Q,NbMaxConstrs);
Q2 = DomainIntersection(Pol2,Q,NbMaxConstrs);
#ifdef DEBUG
fprintf(stdout, "Q1\n");
Polyhedron_Print(stdout,P_VALUE_FMT,Q1);
fprintf(stdout, "Q2\n");
Polyhedron_Print(stdout,P_VALUE_FMT,Q2);
#endif
k = Q1->NbConstraints + Q2->NbConstraints;
Mat = Matrix_Alloc(k, dim);
Vector_Set(Mat->p_Init,0,k*dim);
/* First compute surrounding polyhedron */
j=0;
for (i=0; i<Q1->NbConstraints; i++) {
if ((value_one_p(Q1->Constraint[i][0])) && (value_pos_p(Q1->Constraint[i][INDEX]))) {
/* keep Q1's lower bounds */
for (k=0; k<dim; k++)
value_assign(Mat->p[j][k],Q1->Constraint[i][k]);
j++;
}
}
for (i=0; i<Q2->NbConstraints; i++) {
if ((value_one_p(Q2->Constraint[i][0])) && (value_neg_p(Q2->Constraint[i][INDEX]))) {
/* and keep Q2's upper bounds */
for (k=0; k<dim; k++)
value_assign(Mat->p[j][k],Q2->Constraint[i][k]);
j++;
}
}
Q4 = AddConstraints(Mat->p[0], j, Q, NbMaxConstrs);
Matrix_Free(Mat);
#ifdef debug
fprintf(stderr, "Q4 surrounding polyhedron\n");
Polyhderon_Print(stderr,P_VALUE_FMT, Q4);
#endif
/* if surrounding polyhedron is empty, D1>D2 */
if (emptyQ(Q4)) {
res = 1;
#ifdef debug
fprintf(stderr, "Surrounding polyhedron is empty\n");
#endif
goto LTQdone2;
}
/* Test if Q1 < Q2 */
/* Build a constraint array for >= Q1 and <= Q2 */
Mat = Matrix_Alloc(2,dim);
Vector_Set(Mat->p_Init,0,2*dim);
/* Choose a contraint from Q1 */
for (i=0; i<Q1->NbConstraints; i++) {
if (value_zero_p(Q1->Constraint[i][0])) {
/* Equality */
if (value_zero_p(Q1->Constraint[i][INDEX])) {
/* Ignore side constraint (they are in Q) */
continue;
}
else if (value_neg_p(Q1->Constraint[i][INDEX])) {
/* copy -constraint to Mat */
value_set_si(Mat->p[0][0],1);
for (k=1; k<dim; k++)
value_oppose(Mat->p[0][k],Q1->Constraint[i][k]);
}
else {
/* Copy constraint to Mat */
value_set_si(Mat->p[0][0],1);
for (k=1; k<dim; k++)
value_assign(Mat->p[0][k],Q1->Constraint[i][k]);
}
}
else if(value_neg_p(Q1->Constraint[i][INDEX])) {
/* Upper bound -- make a lower bound from it */
value_set_si(Mat->p[0][0],1);
for (k=1; k<dim; k++)
value_oppose(Mat->p[0][k],Q1->Constraint[i][k]);
}
else {
/* Lower or side bound -- ignore it */
continue;
}
/* Choose a constraint from Q2 */
for (j=0; j<Q2->NbConstraints; j++) {
if (value_zero_p(Q2->Constraint[j][0])) { /* equality */
if (value_zero_p(Q2->Constraint[j][INDEX])) {
/* Ignore side constraint (they are in Q) */
continue;
}
else if (value_pos_p(Q2->Constraint[j][INDEX])) {
/* Copy -constraint to Mat */
value_set_si(Mat->p[1][0],1);
for (k=1; k<dim; k++)
value_oppose(Mat->p[1][k],Q2->Constraint[j][k]);
}
else {
/* Copy constraint to Mat */
value_set_si(Mat->p[1][0],1);
for (k=1; k<dim; k++)
value_assign(Mat->p[1][k],Q2->Constraint[j][k]);
};
}
else if (value_pos_p(Q2->Constraint[j][INDEX])) {
/* Lower bound -- make an upper bound from it */
value_set_si(Mat->p[1][0],1);
for(k=1;k<dim;k++)
value_oppose(Mat->p[1][k],Q2->Constraint[j][k]);
}
else {
/* Upper or side bound -- ignore it */
continue;
};
#ifdef DEBUG
fprintf(stdout, "i=%d j=%d M=\n", i+1, j+1);
Matrix_Print(stdout,P_VALUE_FMT,Mat);
#endif
/* Add Mat to Q and see if anything is made */
Q3 = AddConstraints(Mat->p[0],2,Q,NbMaxConstrs);
#ifdef DEBUG
fprintf(stdout, "Q3\n");
Polyhedron_Print(stdout,P_VALUE_FMT,Q3);
#endif
if (!emptyQ(Q3)) {
Domain_Free(Q3);
#ifdef DEBUG
fprintf(stdout, "not empty\n");
#endif
res = -1;
goto LTQdone;
}
#ifdef DEBUG
fprintf(stdout,"empty\n");
#endif
Domain_Free(Q3);
} /* end for j */
} /* end for i */
res = 1;
LTQdone:
Matrix_Free(Mat);
LTQdone2:
Domain_Free(Q4);
Domain_Free(Q1);
Domain_Free(Q2);
}
Domain_Free(Q);
#ifdef DEBUG
fprintf(stdout, "res = %d\n", res);
#endif
return res;
} /* PolyhedronLTQ */
