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solve send-more-money_lev.smt2

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Signed-off-by: Lev Nachmanson <levnach@microsoft.com>

handle integer vars in random_update

Signed-off-by: Lev Nachmanson <levnach@microsoft.com>

call the assert in gomory_cut and branching to a correct place

Signed-off-by: Lev Nachmanson <levnach@microsoft.com>

fixes in goromy cut

Signed-off-by: Lev Nachmanson <levnach@microsoft.com>

disable x values tracking in random_update

Signed-off-by: Lev Nachmanson <levnach@microsoft.com>

more fixes in gomory cut

Signed-off-by: Lev Nachmanson <levnach@microsoft.com>

change in mk_bound by Nikolaj

Signed-off-by: Lev Nachmanson <levnach@hotmail.com>

fixes in gomory cut and setup

Signed-off-by: Lev Nachmanson <levnach@microsoft.com>

fixes in int_solver

Signed-off-by: Lev Nachmanson <levnach@microsoft.com>

change a printout

Signed-off-by: Lev Nachmanson <levnach@microsoft.com>

fix by Nikolaj in treating terms returned by int_solver

Signed-off-by: Lev Nachmanson <levnach@microsoft.com>

fix syntax

Signed-off-by: Lev Nachmanson <levnach@hotmail.com>

fix a free coefficient bug in bound propagaion and simplify gomory cut

Signed-off-by: Lev Nachmanson <levnach@microsoft.com>

avoid tracking pivoted rows during int_solver::check()
This commit is contained in:
Lev Nachmanson 2017-07-27 10:49:00 -07:00 • committed by Lev Nachmanson
parent aba7dcab3e
commit db8f01894f
31 changed files with 894 additions and 767 deletions
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64
src/util/lp/random_updater.h
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@ -30,67 +30,19 @@ Revision History:
// The class searches for a feasible solution with as many different values of variables as it can find
namespace lp {
template <typename T> struct numeric_pair; // forward definition
class lar_core_solver; // forward definition
class lar_solver; // forward definition
class random_updater {
struct interval {
bool upper_bound_is_set;
numeric_pair<mpq> upper_bound;
bool low_bound_is_set;
numeric_pair<mpq> low_bound;
interval() : upper_bound_is_set(false),
low_bound_is_set(false) {}
void set_low_bound(const numeric_pair<mpq> & v) {
if (low_bound_is_set) {
low_bound = std::max(v, low_bound);
} else {
low_bound = v;
low_bound_is_set = true;
}
}
void set_upper_bound(const numeric_pair<mpq> & v) {
if (upper_bound_is_set) {
upper_bound = std::min(v, upper_bound);
} else {
upper_bound = v;
upper_bound_is_set = true;
}
}
bool is_empty() const {return
upper_bound_is_set && low_bound_is_set && low_bound >= upper_bound;
}
bool low_bound_holds(const numeric_pair<mpq> & a) const {
return low_bound_is_set == false || a >= low_bound;
}
bool upper_bound_holds(const numeric_pair<mpq> & a) const {
return upper_bound_is_set == false || a <= upper_bound;
}
bool contains(const numeric_pair<mpq> & a) const {
return low_bound_holds(a) && upper_bound_holds(a);
}
std::string lbs() { return low_bound_is_set ? T_to_string(low_bound):std::string("inf");}
std::string rbs() { return upper_bound_is_set? T_to_string(upper_bound):std::string("inf");}
std::string to_str() { return std::string("[")+ lbs() + ", " + rbs() + "]";}
};
std::set<var_index> m_var_set;
lar_core_solver & m_core_solver;
unsigned range;
linear_combination_iterator<mpq>* m_column_j; // the actual column
interval find_shift_interval(unsigned j);
interval get_interval_of_non_basic_var(unsigned j);
lar_solver & m_lar_solver;
unsigned m_range;
void add_column_to_sets(unsigned j);
void random_shift_var(unsigned j);
bool random_shift_var(unsigned j);
std::unordered_map<numeric_pair<mpq>, unsigned> m_values; // it maps a value to the number of time it occurs
void diminish_interval_to_leave_basic_vars_feasible(numeric_pair<mpq> &nb_x, interval & inter);
void shift_var(unsigned j, interval & r);
void diminish_interval_for_basic_var(numeric_pair<mpq> &nb_x, unsigned j, mpq & a, interval & r);
numeric_pair<mpq> get_random_from_interval(interval & r);
void add_value(numeric_pair<mpq>& v);
void remove_value(numeric_pair<mpq> & v);
bool shift_var(unsigned j);
void add_value(const numeric_pair<mpq>& v);
void remove_value(const numeric_pair<mpq> & v);
public:
random_updater(lar_core_solver & core_solver, const vector<unsigned> & column_list);
random_updater(lar_solver & solver, const vector<unsigned> & column_list);
void update();
};
}