int rp_operator_newton::reduce(rp_box b)
{
bool proof = true;
for (int i=0; i<_arity; ++i)
{
int v = _v[i];
rp_interval aux, save;
rp_interval_add(aux,rp_ivector_elem(_unknown,i),rp_box_elem(_midpoint,v));
rp_interval_copy(save,rp_box_elem(b,v));
if (!(rp_interval_strictly_included(aux,save))) proof = false;
rp_interval_inter(rp_box_elem(b,v),save,aux);
if (rp_interval_empty(rp_box_elem(b,v)))
{
return( 0 );
}
}
if (proof) rp_box_set_safe(b);
return( 1 );
}
// Application function
// b(x) := hull (b(x) inter initial_domain)
int rp_operator_domain::apply(rp_box b)
{
DREAL_LOG_DEBUG << "rp_operator_domain::apply";
/* Rounding for discrete variables */
if (rp_variable_integer(_x))
{
rp_interval_trunc(rp_box_elem(b,_id));
if (rp_interval_empty(rp_box_elem(b,_id)))
{
return( 0 );
}
}
/* Intersection with initial domain */
return( rp_union_inter_iu(rp_box_elem(b,_id),rp_variable_domain(_x)) );
}
// Application of operator to reduce the box b
int rp_operator_piecewise::apply(rp_box b)
{
DREAL_LOG_DEBUG << "rp_operator_piecewise::apply";
// Check each piece Ij:Cj, if Cj violated then the elements of Ij
// are removed from the domain of the main variable of _c
for (int i=0; i<rp_ctr_piecewise_arity(_c); ++i)
{
int violated = 0, j = 0;
while ((!violated) && (j<rp_ctr_piecewise_elem_size(_c,i)))
{
if (rp_ctr_num_unfeasible(rp_ctr_piecewise_elem_ctrnum(_c,i,j),b))
{
violated = 1;
}
else ++j;
}
if (violated)
{
// domain restriction dom(var) := dom(var) \ Ij
rp_interval aux;
rp_interval_copy(aux,rp_box_elem(b,rp_ctr_piecewise_var(_c)));
rp_interval_setminus(rp_box_elem(b,rp_ctr_piecewise_var(_c)),
aux,
rp_ctr_piecewise_elem_dom(_c,i));
if (rp_interval_empty(rp_box_elem(b,rp_ctr_piecewise_var(_c))))
{
return( 0 );
}
}
}
// Check whether the domain of the main variable of _c
// intersects at least one Ij
int intersect = 0, i = 0;
while ((!intersect) && (i<rp_ctr_piecewise_arity(_c)))
{
if (!rp_interval_disjoint(rp_box_elem(b,rp_ctr_piecewise_var(_c)),
rp_ctr_piecewise_elem_dom(_c,i)))
{
intersect = 1;
}
else ++i;
}
return( intersect );
}
/* Returns true if no point of b is solution of c */
int rp_ctr_numeq_unfeasible(rp_ctr_num c, rp_box b)
{
int res;
if ((!rp_expression_eval(rp_ctr_num_left(c),b)) ||
(!rp_expression_eval(rp_ctr_num_right(c),b)))
{
/* at least one expression has an empty range over b */
res = 1;
}
else
{
/* unfeasible if empty intersection */
rp_interval i;
rp_interval_inter(i,rp_expression_val(rp_ctr_num_left(c)),
rp_expression_val(rp_ctr_num_right(c)));
res = rp_interval_empty(i);
}
return( res );
}
// Application of operator to reduce the box b
int rp_operator_3b::apply(rp_box b)
{
DREAL_LOG_DEBUG << "rp_operator_3b::apply";
// domain to be reduced
double u = rp_binf(rp_box_elem(b,_v));
double v = rp_bsup(rp_box_elem(b,_v));
double x;
// Reduction of left bound [a,x]
RP_ROUND_UPWARD();
x = u + _improve * (v-u);
if (x>=v)
{
// reduction of whole domain
return _o->apply(b);
}
else
{
rp_box_copy(_baux,b);
rp_bsup(rp_box_elem(_baux,_v)) = x;
if (!_o->apply(_baux))
{
rp_binf(rp_box_elem(b,_v)) = x;
}
}
// Reduction of right bound [x,b]
RP_ROUND_DOWNWARD();
x = v - _improve * (v-u);
rp_box_copy(_baux,b);
rp_binf(rp_box_elem(_baux,_v)) = x;
if (!_o->apply(_baux))
{
rp_bsup(rp_box_elem(b,_v)) = x;
}
return( !(rp_interval_empty(rp_box_elem(b,_v))) );
}
