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add cancellations
Signed-off-by: Lev Nachmanson <levnach@hotmail.com> syntax errors Signed-off-by: Lev Nachmanson <levnach@microsoft.com> use std::vector instead of vector in cut_solver temporarily Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fix in is_upper_bound, is_lower_bound Signed-off-by: Lev Nachmanson <levnach@hotmail.com> add bound() for polynomial, needs more testing Signed-off-by: Lev Nachmanson <levnach@hotmail.com> work on resolve Signed-off-by: Lev Nachmanson <levnach@microsoft.com> implement resolve() Signed-off-by: Lev Nachmanson <levnach@microsoft.com> implement improves() Signed-off-by: Lev Nachmanson <levnach@hotmail.com> replace low_bound by lower_bound Signed-off-by: Lev Nachmanson <levnach@hotmail.com> work on cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> work on cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> better printing in cut_solver.h Signed-off-by: Lev Nachmanson <levnach@hotmail.com> add value vector to cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> work on bound propagaion for cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> bound propagation for integer inequalites Signed-off-by: Lev Nachmanson <levnach@hotmail.com> bound propagation for integer inequalites Signed-off-by: Lev Nachmanson <levnach@hotmail.com> bound propagattions on integers Signed-off-by: Lev Nachmanson <levnach@hotmail.com> adding m_explanation field to cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> simplify bound propagation in cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> calculate conflict explanation Signed-off-by: Lev Nachmanson <levnach@hotmail.com> change m_explanation type to a set Signed-off-by: Lev Nachmanson <levnach@hotmail.com> making cut_solver a member of int_solver, missing push/pop support Signed-off-by: Lev Nachmanson <levnach@hotmail.com> Nikolaj's comments Signed-off-by: Lev Nachmanson <levnach@hotmail.com> Nikolaj's comments Signed-off-by: Lev Nachmanson <levnach@hotmail.com> return explanations from cut_solver and hook up push/pop Signed-off-by: Lev Nachmanson <levnach@hotmail.com> hook up push/pop Signed-off-by: Lev Nachmanson <levnach@hotmail.com> using resize of std::vector Signed-off-by: Lev Nachmanson <levnach@hotmail.com> it is a big squashed commit Signed-off-by: Lev Nachmanson <levnach@hotmail.com> rename hpp to cpp Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fixes in push/pop of cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> return simple inequalities a part of a conflict Signed-off-by: Lev Nachmanson <levnach@hotmail.com> work on propagation and the main loop Signed-off-by: Lev Nachmanson <levnach@hotmail.com> add file Signed-off-by: Lev Nachmanson <levnach@hotmail.com> work on cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> init m_v[j], the var values only when j is fixed Signed-off-by: Lev Nachmanson <levnach@hotmail.com> cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> handle decide in cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> start on resolve_conflict Signed-off-by: Lev Nachmanson <levnach@hotmail.com> start on resolve_conflict Signed-off-by: Lev Nachmanson <levnach@hotmail.com> remove cut_solver_def.h Signed-off-by: Lev Nachmanson <levnach@hotmail.com> in the middle Signed-off-by: Lev Nachmanson <levnach@hotmail.com> change signature of resolve Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fix the domain of the decided var Signed-off-by: Lev Nachmanson <levnach@hotmail.com> work on tightening of ineqs Signed-off-by: Lev Nachmanson <levnach@hotmail.com> work on tight ineqs Signed-off-by: Lev Nachmanson <levnach@hotmail.com> work on tightening Signed-off-by: Lev Nachmanson <levnach@hotmail.com> work on tightening Signed-off-by: Lev Nachmanson <levnach@hotmail.com> resolve conflict Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fix in usage of resolve() Signed-off-by: Lev Nachmanson <levnach@hotmail.com> work on conflict resolution Signed-off-by: Lev Nachmanson <levnach@hotmail.com> cut_solver is not a template Signed-off-by: Lev Nachmanson <levnach@hotmail.com> represent var_info as a class, not a struct Signed-off-by: Lev Nachmanson <levnach@hotmail.com> make literal a class Signed-off-by: Lev Nachmanson <levnach@hotmail.com> better resolve_conflict scheme, and switch to *constraints in literals Signed-off-by: Lev Nachmanson <levnach@hotmail.com> debug conflict resolution in cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> switch to vector Signed-off-by: Lev Nachmanson <levnach@hotmail.com> remove nondetermenistic behavior from cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> debug resolve conflict Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fix backjump Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fix backjump Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fix backjump Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fix backjump Signed-off-by: Lev Nachmanson <levnach@hotmail.com> dumb explanation Signed-off-by: Lev Nachmanson <levnach@hotmail.com> get rid of a parameter Signed-off-by: Lev Nachmanson <levnach@hotmail.com> add lemmas origins Signed-off-by: Lev Nachmanson <levnach@hotmail.com> use lemma_origins to provide correct explanations Signed-off-by: Lev Nachmanson <levnach@hotmail.com> use lemma_origins to provide correct explanations Signed-off-by: Lev Nachmanson <levnach@hotmail.com> store lemmas in a separate vector Signed-off-by: Lev Nachmanson <levnach@hotmail.com> use std::unordered_set for m_dependent_constraints Signed-off-by: Lev Nachmanson <levnach@hotmail.com> use std::unordered_set for m_dependent_constraints Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fix bugs with lemmas Signed-off-by: Lev Nachmanson <levnach@hotmail.com> finding conflicting cores Signed-off-by: Lev Nachmanson <levnach@hotmail.com> switch from changed variables to active_set Signed-off-by: Lev Nachmanson <levnach@hotmail.com> less active constraints Signed-off-by: Lev Nachmanson <levnach@hotmail.com> work on cut_solver.h Signed-off-by: Lev Nachmanson <levnach@hotmail.com> propagate simple constraing immediately Signed-off-by: Lev Nachmanson <levnach@hotmail.com> propagate simple constraints immediately Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fixing bugs with active set Signed-off-by: Lev Nachmanson <levnach@hotmail.com> remove const_cast Signed-off-by: Lev Nachmanson <levnach@hotmail.com> towards unbounded variables Signed-off-by: Lev Nachmanson <levnach@hotmail.com> toward unbounded variables Signed-off-by: Lev Nachmanson <levnach@hotmail.com> toward unbounded variables Signed-off-by: Lev Nachmanson <levnach@hotmail.com> make lemmas_origins a set Signed-off-by: Lev Nachmanson <levnach@hotmail.com> use correct hash and equal in m_lemma_origins Signed-off-by: Lev Nachmanson <levnach@hotmail.com> add testing code Signed-off-by: Lev Nachmanson <levnach@hotmail.com> add testing code Signed-off-by: Lev Nachmanson <levnach@hotmail.com> debug Signed-off-by: Lev Nachmanson <levnach@hotmail.com> debug unlimited vars Signed-off-by: Lev Nachmanson <levnach@hotmail.com> take in Nikolaj's comments and improvements Signed-off-by: Lev Nachmanson <levnach@hotmail.com> address the comments Signed-off-by: Lev Nachmanson <levnach@hotmail.com> handle unlimited vars in check_inconsistent Signed-off-by: Lev Nachmanson <levnach@hotmail.com> debug Signed-off-by: Lev Nachmanson <levnach@hotmail.com> detect trivial polynomials in resolve Signed-off-by: Lev Nachmanson <levnach@hotmail.com> Nikolaj's changes Signed-off-by: Lev Nachmanson <levnach@hotmail.com> simplify handling of m_global_bound_var Signed-off-by: Lev Nachmanson <levnach@hotmail.com> decide on m_global_bound_var if it is not fixed Signed-off-by: Lev Nachmanson <levnach@hotmail.com> simplify m_global_bound_var Signed-off-by: Lev Nachmanson <levnach@hotmail.com> remove m_global_bound_var, simplify the indexing of var_infos of cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> do not run cut_solver with vars without any bound Signed-off-by: Lev Nachmanson <levnach@hotmail.com> small changes Signed-off-by: Lev Nachmanson <levnach@hotmail.com> add cancellation in cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> do not pop lemmas during a cut_solver run Signed-off-by: Lev Nachmanson <levnach@hotmail.com> treating cut_solver as an heurisitic Signed-off-by: Lev Nachmanson <levnach@hotmail.com> prepare for cut_solver returning undef Signed-off-by: Lev Nachmanson <levnach@hotmail.com> simplify work with active_set in cut_solver, add stats Signed-off-by: Lev Nachmanson <levnach@hotmail.com> simplify var_info literals Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fix a bug in fill_conflict_explanation Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fix a bug in the conflict explanation Signed-off-by: Lev Nachmanson <levnach@hotmail.com> add timeout to validate_* in theory_lra.cpp Signed-off-by: Lev Nachmanson <levnach@hotmail.com> simplify cut_solver, no special treatment for simple constraints Signed-off-by: Lev Nachmanson <levnach@hotmail.com> cleanup the cancel story Signed-off-by: Lev Nachmanson <levnach@hotmail.com> cleanup cancelling Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fix a bug in push/pop of cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> extract a method in int_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> some progress with the new scheme Signed-off-by: Lev Nachmanson <levnach@hotmail.com> add testing code Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fixes in test and in literal creation Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fix a bug in bound propagation in cut_solver.h Signed-off-by: Lev Nachmanson <levnach@hotmail.com> simplify cut_solver Signed-off-by: Lev Nachmanson <levnach@hotmail.com> provide valid conflict explanation Signed-off-by: Lev Nachmanson <levnach@hotmail.com> use a lazy push in stacked_map Signed-off-by: Lev Nachmanson <levnach@hotmail.com> use a lazy push in stacked_map Signed-off-by: Lev Nachmanson <levnach@hotmail.com> optimize stack operations on var_info's domains Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fix a bug in tightening Signed-off-by: Lev Nachmanson <levnach@hotmail.com> use the standard tactics from qflia_tactic Signed-off-by: Lev Nachmanson <levnach@hotmail.com> spread the var domain stack over literals Signed-off-by: Lev Nachmanson <levnach@hotmail.com> spread the var domain stack over literals Signed-off-by: Lev Nachmanson <levnach@hotmail.com> avoid cycling in cut_solver.h and fixes in push/pop Signed-off-by: Lev Nachmanson <levnach@hotmail.com> fixes after rebase Signed-off-by: Lev Nachmanson <levnach@hotmail.com>
This commit is contained in:
Lev Nachmanson
parent
58ca4518e5
commit
6202b2f2e4
103 changed files with 7035 additions and 5106 deletions
569
src/util/lp/lp_solver_def.h
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569
src/util/lp/lp_solver_def.h
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/*++
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Copyright (c) 2017 Microsoft Corporation
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Module Name:
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<name>
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Abstract:
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<abstract>
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Author:
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Lev Nachmanson (levnach)
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Revision History:
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--*/
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#include <string>
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#include <algorithm>
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#include "util/vector.h"
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#include "util/lp/lp_solver.h"
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namespace lp {
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template <typename T, typename X> column_info<T> * lp_solver<T, X>::get_or_create_column_info(unsigned column) {
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auto it = m_map_from_var_index_to_column_info.find(column);
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return (it == m_map_from_var_index_to_column_info.end())? (m_map_from_var_index_to_column_info[column] = new column_info<T>(static_cast<unsigned>(-1))) : it->second;
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}
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template <typename T, typename X>
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std::string lp_solver<T, X>::get_column_name(unsigned j) const { // j here is the core solver index
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auto it = this->m_core_solver_columns_to_external_columns.find(j);
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if (it == this->m_core_solver_columns_to_external_columns.end())
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return std::string("x")+T_to_string(j);
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unsigned external_j = it->second;
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auto t = this->m_map_from_var_index_to_column_info.find(external_j);
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if (t == this->m_map_from_var_index_to_column_info.end()) {
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return std::string("x") +T_to_string(external_j);
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}
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return t->second->get_name();
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}
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template <typename T, typename X> T lp_solver<T, X>::get_column_cost_value(unsigned j, column_info<T> * ci) const {
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if (ci->is_fixed()) {
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return ci->get_cost() * ci->get_fixed_value();
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}
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return ci->get_cost() * get_column_value(j);
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}
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template <typename T, typename X> void lp_solver<T, X>::add_constraint(lp_relation relation, T right_side, unsigned row_index) {
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lp_assert(m_constraints.find(row_index) == m_constraints.end());
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lp_constraint<T, X> cs(right_side, relation);
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m_constraints[row_index] = cs;
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}
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template <typename T, typename X> void lp_solver<T, X>::give_symbolic_name_to_column(std::string name, unsigned column) {
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auto it = m_map_from_var_index_to_column_info.find(column);
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column_info<T> *ci;
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if (it == m_map_from_var_index_to_column_info.end()){
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m_map_from_var_index_to_column_info[column] = ci = new column_info<T>;
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} else {
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ci = it->second;
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}
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ci->set_name(name);
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m_names_to_columns[name] = column;
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}
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template <typename T, typename X> T lp_solver<T, X>::get_column_value_by_name(std::string name) const {
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auto it = m_names_to_columns.find(name);
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if (it == m_names_to_columns.end()) {
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std::stringstream s;
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s << "get_column_value_by_name " << name;
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throw_exception(s.str());
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}
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return get_column_value(it -> second);
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}
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// returns -1 if not found
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template <typename T, typename X> int lp_solver<T, X>::get_column_index_by_name(std::string name) const {
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auto t = m_names_to_columns.find(name);
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if (t == m_names_to_columns.end()) {
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return -1;
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}
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return t->second;
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}
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template <typename T, typename X> lp_solver<T, X>::~lp_solver(){
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if (m_A != nullptr) {
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delete m_A;
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}
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for (auto t : m_map_from_var_index_to_column_info) {
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delete t.second;
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}
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}
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template <typename T, typename X> void lp_solver<T, X>::flip_costs() {
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for (auto t : m_map_from_var_index_to_column_info) {
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column_info<T> *ci = t.second;
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ci->set_cost(-ci->get_cost());
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}
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}
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template <typename T, typename X> bool lp_solver<T, X>::problem_is_empty() {
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for (auto & c : m_A_values)
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if (c.second.size())
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return false;
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return true;
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}
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template <typename T, typename X> void lp_solver<T, X>::scale() {
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if (numeric_traits<T>::precise() || m_settings.use_scaling == false) {
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m_column_scale.clear();
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m_column_scale.resize(m_A->column_count(), one_of_type<T>());
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return;
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}
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T smin = T(m_settings.scaling_minimum);
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T smax = T(m_settings.scaling_maximum);
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scaler<T, X> scaler(m_b, *m_A, smin, smax, m_column_scale, this->m_settings);
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if (!scaler.scale()) {
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unscale();
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}
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}
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template <typename T, typename X> void lp_solver<T, X>::print_rows_scale_stats(std::ostream & out) {
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out << "rows max" << std::endl;
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for (unsigned i = 0; i < m_A->row_count(); i++) {
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print_row_scale_stats(i, out);
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}
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out << std::endl;
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}
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template <typename T, typename X> void lp_solver<T, X>::print_columns_scale_stats(std::ostream & out) {
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out << "columns max" << std::endl;
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for (unsigned i = 0; i < m_A->column_count(); i++) {
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print_column_scale_stats(i, out);
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}
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out << std::endl;
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}
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template <typename T, typename X> void lp_solver<T, X>::print_row_scale_stats(unsigned i, std::ostream & out) {
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out << "(" << std::min(m_A->get_min_abs_in_row(i), abs(m_b[i])) << " ";
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out << std::max(m_A->get_max_abs_in_row(i), abs(m_b[i])) << ")";
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}
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template <typename T, typename X> void lp_solver<T, X>::print_column_scale_stats(unsigned j, std::ostream & out) {
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out << "(" << m_A->get_min_abs_in_row(j) << " ";
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out << m_A->get_max_abs_in_column(j) << ")";
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}
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template <typename T, typename X> void lp_solver<T, X>::print_scale_stats(std::ostream & out) {
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print_rows_scale_stats(out);
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print_columns_scale_stats(out);
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}
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template <typename T, typename X> void lp_solver<T, X>::get_max_abs_in_row(std::unordered_map<unsigned, T> & row_map) {
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T ret = numeric_traits<T>::zero();
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for (auto jp : row_map) {
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T ac = numeric_traits<T>::abs(jp->second);
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if (ac > ret) {
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ret = ac;
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}
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}
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return ret;
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}
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template <typename T, typename X> void lp_solver<T, X>::pin_vars_on_row_with_sign(std::unordered_map<unsigned, T> & row, T sign ) {
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for (auto t : row) {
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unsigned j = t.first;
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column_info<T> * ci = m_map_from_var_index_to_column_info[j];
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T a = t.second;
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if (a * sign > numeric_traits<T>::zero()) {
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lp_assert(ci->upper_bound_is_set());
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ci->set_fixed_value(ci->get_upper_bound());
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} else {
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lp_assert(ci->lower_bound_is_set());
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ci->set_fixed_value(ci->get_lower_bound());
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}
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}
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}
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template <typename T, typename X> bool lp_solver<T, X>::get_minimal_row_value(std::unordered_map<unsigned, T> & row, T & lower_bound) {
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lower_bound = numeric_traits<T>::zero();
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for (auto & t : row) {
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T a = t.second;
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column_info<T> * ci = m_map_from_var_index_to_column_info[t.first];
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if (a > numeric_traits<T>::zero()) {
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if (ci->lower_bound_is_set()) {
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lower_bound += ci->get_lower_bound() * a;
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} else {
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return false;
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}
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} else {
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if (ci->upper_bound_is_set()) {
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lower_bound += ci->get_upper_bound() * a;
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} else {
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return false;
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}
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}
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}
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return true;
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}
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template <typename T, typename X> bool lp_solver<T, X>::get_maximal_row_value(std::unordered_map<unsigned, T> & row, T & lower_bound) {
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lower_bound = numeric_traits<T>::zero();
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for (auto & t : row) {
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T a = t.second;
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column_info<T> * ci = m_map_from_var_index_to_column_info[t.first];
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if (a < numeric_traits<T>::zero()) {
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if (ci->lower_bound_is_set()) {
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lower_bound += ci->get_lower_bound() * a;
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} else {
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return false;
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}
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} else {
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if (ci->upper_bound_is_set()) {
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lower_bound += ci->get_upper_bound() * a;
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} else {
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return false;
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}
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}
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}
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return true;
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}
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template <typename T, typename X> bool lp_solver<T, X>::row_is_zero(std::unordered_map<unsigned, T> & row) {
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for (auto & t : row) {
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if (!is_zero(t.second))
|
||||
return false;
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
template <typename T, typename X> bool lp_solver<T, X>::row_e_is_obsolete(std::unordered_map<unsigned, T> & row, unsigned row_index) {
|
||||
T rs = m_constraints[row_index].m_rs;
|
||||
if (row_is_zero(row)) {
|
||||
if (!is_zero(rs))
|
||||
m_status = lp_status::INFEASIBLE;
|
||||
return true;
|
||||
}
|
||||
|
||||
T lower_bound;
|
||||
bool lb = get_minimal_row_value(row, lower_bound);
|
||||
if (lb) {
|
||||
T diff = lower_bound - rs;
|
||||
if (!val_is_smaller_than_eps(diff, m_settings.refactor_tolerance)){
|
||||
// lower_bound > rs + m_settings.refactor_epsilon
|
||||
m_status = lp_status::INFEASIBLE;
|
||||
return true;
|
||||
}
|
||||
if (val_is_smaller_than_eps(-diff, m_settings.refactor_tolerance)){
|
||||
pin_vars_down_on_row(row);
|
||||
return true;
|
||||
}
|
||||
}
|
||||
|
||||
T upper_bound;
|
||||
bool ub = get_maximal_row_value(row, upper_bound);
|
||||
if (ub) {
|
||||
T diff = rs - upper_bound;
|
||||
if (!val_is_smaller_than_eps(diff, m_settings.refactor_tolerance)) {
|
||||
// upper_bound < rs - m_settings.refactor_tolerance
|
||||
m_status = lp_status::INFEASIBLE;
|
||||
return true;
|
||||
}
|
||||
if (val_is_smaller_than_eps(-diff, m_settings.refactor_tolerance)){
|
||||
pin_vars_up_on_row(row);
|
||||
return true;
|
||||
}
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
template <typename T, typename X> bool lp_solver<T, X>::row_ge_is_obsolete(std::unordered_map<unsigned, T> & row, unsigned row_index) {
|
||||
T rs = m_constraints[row_index].m_rs;
|
||||
if (row_is_zero(row)) {
|
||||
if (rs > zero_of_type<X>())
|
||||
m_status = lp_status::INFEASIBLE;
|
||||
return true;
|
||||
}
|
||||
|
||||
T upper_bound;
|
||||
if (get_maximal_row_value(row, upper_bound)) {
|
||||
T diff = rs - upper_bound;
|
||||
if (!val_is_smaller_than_eps(diff, m_settings.refactor_tolerance)) {
|
||||
// upper_bound < rs - m_settings.refactor_tolerance
|
||||
m_status = lp_status::INFEASIBLE;
|
||||
return true;
|
||||
}
|
||||
if (val_is_smaller_than_eps(-diff, m_settings.refactor_tolerance)){
|
||||
pin_vars_up_on_row(row);
|
||||
return true;
|
||||
}
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
template <typename T, typename X> bool lp_solver<T, X>::row_le_is_obsolete(std::unordered_map<unsigned, T> & row, unsigned row_index) {
|
||||
T lower_bound;
|
||||
T rs = m_constraints[row_index].m_rs;
|
||||
if (row_is_zero(row)) {
|
||||
if (rs < zero_of_type<X>())
|
||||
m_status = lp_status::INFEASIBLE;
|
||||
return true;
|
||||
}
|
||||
|
||||
if (get_minimal_row_value(row, lower_bound)) {
|
||||
T diff = lower_bound - rs;
|
||||
if (!val_is_smaller_than_eps(diff, m_settings.refactor_tolerance)){
|
||||
// lower_bound > rs + m_settings.refactor_tolerance
|
||||
m_status = lp_status::INFEASIBLE;
|
||||
return true;
|
||||
}
|
||||
if (val_is_smaller_than_eps(-diff, m_settings.refactor_tolerance)){
|
||||
pin_vars_down_on_row(row);
|
||||
return true;
|
||||
}
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
// analyse possible max and min values that are derived from var boundaries
|
||||
// Let us say that the we have a "ge" constraint, and the min value is equal to the rs.
|
||||
// Then we know what values of the variables are. For each positive coeff of the row it has to be
|
||||
// the low boundary of the var and for a negative - the upper.
|
||||
|
||||
// this routing also pins the variables to the boundaries
|
||||
template <typename T, typename X> bool lp_solver<T, X>::row_is_obsolete(std::unordered_map<unsigned, T> & row, unsigned row_index ) {
|
||||
auto & constraint = m_constraints[row_index];
|
||||
switch (constraint.m_relation) {
|
||||
case lp_relation::Equal:
|
||||
return row_e_is_obsolete(row, row_index);
|
||||
|
||||
case lp_relation::Greater_or_equal:
|
||||
return row_ge_is_obsolete(row, row_index);
|
||||
|
||||
case lp_relation::Less_or_equal:
|
||||
return row_le_is_obsolete(row, row_index);
|
||||
}
|
||||
lp_unreachable();
|
||||
return false; // it is unreachable
|
||||
}
|
||||
|
||||
template <typename T, typename X> void lp_solver<T, X>::remove_fixed_or_zero_columns() {
|
||||
for (auto & i_row : m_A_values) {
|
||||
remove_fixed_or_zero_columns_from_row(i_row.first, i_row.second);
|
||||
}
|
||||
}
|
||||
|
||||
template <typename T, typename X> void lp_solver<T, X>::remove_fixed_or_zero_columns_from_row(unsigned i, std::unordered_map<unsigned, T> & row) {
|
||||
auto & constraint = m_constraints[i];
|
||||
vector<unsigned> removed;
|
||||
for (auto & col : row) {
|
||||
unsigned j = col.first;
|
||||
lp_assert(m_map_from_var_index_to_column_info.find(j) != m_map_from_var_index_to_column_info.end());
|
||||
column_info<T> * ci = m_map_from_var_index_to_column_info[j];
|
||||
if (ci->is_fixed()) {
|
||||
removed.push_back(j);
|
||||
T aj = col.second;
|
||||
constraint.m_rs -= aj * ci->get_fixed_value();
|
||||
} else {
|
||||
if (numeric_traits<T>::is_zero(col.second)){
|
||||
removed.push_back(j);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
for (auto j : removed) {
|
||||
row.erase(j);
|
||||
}
|
||||
}
|
||||
|
||||
template <typename T, typename X> unsigned lp_solver<T, X>::try_to_remove_some_rows() {
|
||||
vector<unsigned> rows_to_delete;
|
||||
for (auto & t : m_A_values) {
|
||||
if (row_is_obsolete(t.second, t.first)) {
|
||||
rows_to_delete.push_back(t.first);
|
||||
}
|
||||
|
||||
if (m_status == lp_status::INFEASIBLE) {
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
if (rows_to_delete.size() > 0) {
|
||||
for (unsigned k : rows_to_delete) {
|
||||
m_A_values.erase(k);
|
||||
}
|
||||
}
|
||||
remove_fixed_or_zero_columns();
|
||||
return static_cast<unsigned>(rows_to_delete.size());
|
||||
}
|
||||
|
||||
template <typename T, typename X> void lp_solver<T, X>::cleanup() {
|
||||
int n = 0; // number of deleted rows
|
||||
int d;
|
||||
while ((d = try_to_remove_some_rows() > 0))
|
||||
n += d;
|
||||
|
||||
if (n == 1) {
|
||||
LP_OUT(m_settings, "deleted one row" << std::endl);
|
||||
} else if (n) {
|
||||
LP_OUT(m_settings, "deleted " << n << " rows" << std::endl);
|
||||
}
|
||||
}
|
||||
|
||||
template <typename T, typename X> void lp_solver<T, X>::map_external_rows_to_core_solver_rows() {
|
||||
unsigned size = 0;
|
||||
for (auto & row : m_A_values) {
|
||||
m_external_rows_to_core_solver_rows[row.first] = size;
|
||||
m_core_solver_rows_to_external_rows[size] = row.first;
|
||||
size++;
|
||||
}
|
||||
}
|
||||
|
||||
template <typename T, typename X> void lp_solver<T, X>::map_external_columns_to_core_solver_columns() {
|
||||
unsigned size = 0;
|
||||
for (auto & row : m_A_values) {
|
||||
for (auto & col : row.second) {
|
||||
if (col.second == numeric_traits<T>::zero() || m_map_from_var_index_to_column_info[col.first]->is_fixed()) {
|
||||
throw_exception("found fixed column");
|
||||
}
|
||||
unsigned j = col.first;
|
||||
auto column_info_it = m_map_from_var_index_to_column_info.find(j);
|
||||
lp_assert(column_info_it != m_map_from_var_index_to_column_info.end());
|
||||
|
||||
auto j_column = column_info_it->second->get_column_index();
|
||||
if (!is_valid(j_column)) { // j is a newcomer
|
||||
m_map_from_var_index_to_column_info[j]->set_column_index(size);
|
||||
m_core_solver_columns_to_external_columns[size++] = j;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
template <typename T, typename X> void lp_solver<T, X>::unscale() {
|
||||
delete m_A;
|
||||
m_A = nullptr;
|
||||
fill_A_from_A_values();
|
||||
restore_column_scales_to_one();
|
||||
fill_m_b();
|
||||
}
|
||||
|
||||
template <typename T, typename X> void lp_solver<T, X>::fill_A_from_A_values() {
|
||||
m_A = new static_matrix<T, X>(static_cast<unsigned>(m_A_values.size()), number_of_core_structurals());
|
||||
for (auto & t : m_A_values) {
|
||||
auto row_it = m_external_rows_to_core_solver_rows.find(t.first);
|
||||
lp_assert(row_it != m_external_rows_to_core_solver_rows.end());
|
||||
unsigned row = row_it->second;
|
||||
for (auto k : t.second) {
|
||||
auto column_info_it = m_map_from_var_index_to_column_info.find(k.first);
|
||||
lp_assert(column_info_it != m_map_from_var_index_to_column_info.end());
|
||||
column_info<T> *ci = column_info_it->second;
|
||||
unsigned col = ci->get_column_index();
|
||||
lp_assert(is_valid(col));
|
||||
bool col_is_flipped = m_map_from_var_index_to_column_info[k.first]->is_flipped();
|
||||
if (!col_is_flipped) {
|
||||
(*m_A)(row, col) = k.second;
|
||||
} else {
|
||||
(*m_A)(row, col) = - k.second;
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
template <typename T, typename X> void lp_solver<T, X>::fill_matrix_A_and_init_right_side() {
|
||||
map_external_rows_to_core_solver_rows();
|
||||
map_external_columns_to_core_solver_columns();
|
||||
lp_assert(m_A == nullptr);
|
||||
fill_A_from_A_values();
|
||||
m_b.resize(m_A->row_count());
|
||||
}
|
||||
|
||||
template <typename T, typename X> void lp_solver<T, X>::count_slacks_and_artificials() {
|
||||
for (int i = row_count() - 1; i >= 0; i--) {
|
||||
count_slacks_and_artificials_for_row(i);
|
||||
}
|
||||
}
|
||||
|
||||
template <typename T, typename X> void lp_solver<T, X>::count_slacks_and_artificials_for_row(unsigned i) {
|
||||
lp_assert(this->m_constraints.find(this->m_core_solver_rows_to_external_rows[i]) != this->m_constraints.end());
|
||||
auto & constraint = this->m_constraints[this->m_core_solver_rows_to_external_rows[i]];
|
||||
switch (constraint.m_relation) {
|
||||
case Equal:
|
||||
m_artificials++;
|
||||
break;
|
||||
case Greater_or_equal:
|
||||
m_slacks++;
|
||||
if (this->m_b[i] > 0) {
|
||||
m_artificials++;
|
||||
}
|
||||
break;
|
||||
case Less_or_equal:
|
||||
m_slacks++;
|
||||
if (this->m_b[i] < 0) {
|
||||
m_artificials++;
|
||||
}
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
template <typename T, typename X> T lp_solver<T, X>::lower_bound_shift_for_row(unsigned i) {
|
||||
T ret = numeric_traits<T>::zero();
|
||||
|
||||
auto row = this->m_A_values.find(i);
|
||||
if (row == this->m_A_values.end()) {
|
||||
throw_exception("cannot find row");
|
||||
}
|
||||
for (auto col : row->second) {
|
||||
ret += col.second * this->m_map_from_var_index_to_column_info[col.first]->get_shift();
|
||||
}
|
||||
return ret;
|
||||
}
|
||||
|
||||
template <typename T, typename X> void lp_solver<T, X>::fill_m_b() {
|
||||
for (int i = this->row_count() - 1; i >= 0; i--) {
|
||||
lp_assert(this->m_constraints.find(this->m_core_solver_rows_to_external_rows[i]) != this->m_constraints.end());
|
||||
unsigned external_i = this->m_core_solver_rows_to_external_rows[i];
|
||||
auto & constraint = this->m_constraints[external_i];
|
||||
this->m_b[i] = constraint.m_rs - lower_bound_shift_for_row(external_i);
|
||||
}
|
||||
}
|
||||
|
||||
template <typename T, typename X> T lp_solver<T, X>::get_column_value_with_core_solver(unsigned column, lp_core_solver_base<T, X> * core_solver) const {
|
||||
auto cit = this->m_map_from_var_index_to_column_info.find(column);
|
||||
if (cit == this->m_map_from_var_index_to_column_info.end()) {
|
||||
return numeric_traits<T>::zero();
|
||||
}
|
||||
|
||||
column_info<T> * ci = cit->second;
|
||||
|
||||
if (ci->is_fixed()) {
|
||||
return ci->get_fixed_value();
|
||||
}
|
||||
|
||||
unsigned cj = ci->get_column_index();
|
||||
if (cj != static_cast<unsigned>(-1)) {
|
||||
T v = core_solver->get_var_value(cj) * this->m_column_scale[cj];
|
||||
if (ci->is_free()) {
|
||||
return v;
|
||||
}
|
||||
if (!ci->is_flipped()) {
|
||||
return v + ci->get_lower_bound();
|
||||
}
|
||||
|
||||
// the flipped case when there is only upper bound
|
||||
return -v + ci->get_upper_bound(); //
|
||||
}
|
||||
|
||||
return numeric_traits<T>::zero(); // returns zero for out of boundary columns
|
||||
}
|
||||
|
||||
template <typename T, typename X> void lp_solver<T, X>::set_scaled_cost(unsigned j) {
|
||||
// grab original costs but modify it with the column scales
|
||||
lp_assert(j < this->m_column_scale.size());
|
||||
column_info<T> * ci = this->m_map_from_var_index_to_column_info[this->m_core_solver_columns_to_external_columns[j]];
|
||||
T cost = ci->get_cost();
|
||||
if (ci->is_flipped()){
|
||||
cost *= -1;
|
||||
}
|
||||
lp_assert(ci->is_fixed() == false);
|
||||
this->m_costs[j] = cost * this->m_column_scale[j];
|
||||
}
|
||||
}
|
||||
Loading…
Add table
Add a link
Reference in a new issue