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fix scip support, target 7.0

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This commit is contained in:
Laurent Perron
2020-04-29 18:06:18 +02:00
parent 196871adee
commit 0c6461cfee
1 changed files with 25 additions and 62 deletions
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87
ortools/linear_solver/scip_interface.cc
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@@ -37,7 +37,6 @@
#include "ortools/linear_solver/scip_proto_solver.h"
#include "scip/cons_indicator.h"
#include "scip/scip.h"
#include "scip/scip_param.h"
#include "scip/scip_prob.h"
#include "scip/scipdefplugins.h"
@@ -46,6 +45,7 @@ DEFINE_bool(scip_feasibility_emphasis, false,
"may not result in speedups in some problems.");
namespace operations_research {
class SCIPInterface : public MPSolverInterface {
public:
explicit SCIPInterface(MPSolver* solver);
@@ -106,20 +106,6 @@ class SCIPInterface : public MPSolverInterface {
void* underlying_solver() override { return reinterpret_cast<void*>(scip_); }
// MULTIPLE SOLUTIONS SUPPORT
// The default behavior of scip is to store the top incidentally generated
// integer solutions in the solution pool. The default maximum size is 100.
// This can be adjusted by setting the param limits/maxsol. There is no way
// to ensure that the pool will actually be full.
//
// You can also ask SCIP to enumerate all feasible solutions. Combined with
// an equality or inequality constraint on the objective (after solving once
// to find the optimal solution), you can use this to find all high quality
// solutions. See https://scip.zib.de/doc/html/COUNTER.php. This behavior is
// not supported directly through MPSolver, but in theory can be controlled
// entirely through scip parameters.
bool NextSolution() override;
private:
void SetParameters(const MPSolverParameters& param) override;
void SetRelativeMipGap(double value) override;
@@ -146,10 +132,6 @@ class SCIPInterface : public MPSolverInterface {
MPSolverParameters::IntegerParam param) override;
void SetIntegerParamToUnsupportedValue(MPSolverParameters::IntegerParam param,
int value) override;
// How many solutions SCIP found.
int SolutionCount();
// Copy sol from SCIP to MPSolver.
void SetSolution(SCIP_SOL* solution);
util::Status CreateSCIP();
void DeleteSCIP();
@@ -165,7 +147,7 @@ class SCIPInterface : public MPSolverInterface {
SCIP* scip_;
std::vector<SCIP_VAR*> scip_variables_;
std::vector<SCIP_CONS*> scip_constraints_;
int current_solution_index_ = 0;
bool branching_priority_reset_ = false;
};
SCIPInterface::SCIPInterface(MPSolver* solver)
@@ -177,7 +159,6 @@ SCIPInterface::~SCIPInterface() { DeleteSCIP(); }
void SCIPInterface::Reset() {
DeleteSCIP();
scip_constraint_handler_.reset();
status_ = CreateSCIP();
ResetExtractionInformation();
}
@@ -594,8 +575,10 @@ MPSolver::ResultStatus SCIPInterface::Solve(const MPSolverParameters& param) {
// Note that SCIP does not provide any incrementality.
// TODO(user): Is that still true now (2018) ?
if (param.GetIntegerParam(MPSolverParameters::INCREMENTALITY) ==
MPSolverParameters::INCREMENTALITY_OFF) {
MPSolverParameters::INCREMENTALITY_OFF ||
branching_priority_reset_) {
Reset();
branching_priority_reset_ = false;
}
// Set log level.
@@ -686,12 +669,21 @@ MPSolver::ResultStatus SCIPInterface::Solve(const MPSolverParameters& param) {
: SCIPsolve(scip_));
VLOG(1) << absl::StrFormat("Solved in %s.",
absl::FormatDuration(timer.GetDuration()));
current_solution_index_ = 0;
// Get the results.
SCIP_SOL* const solution = SCIPgetBestSol(scip_);
if (solution != nullptr) {
// If optimal or feasible solution is found.
SetSolution(solution);
objective_value_ = SCIPgetSolOrigObj(scip_, solution);
VLOG(1) << "objective=" << objective_value_;
for (int i = 0; i < solver_->variables_.size(); ++i) {
MPVariable* const var = solver_->variables_[i];
const int var_index = var->index();
const double val =
SCIPgetSolVal(scip_, solution, scip_variables_[var_index]);
var->set_solution_value(val);
VLOG(3) << var->name() << "=" << val;
}
} else {
VLOG(1) << "No feasible solution found.";
}
@@ -735,19 +727,6 @@ MPSolver::ResultStatus SCIPInterface::Solve(const MPSolverParameters& param) {
return result_status_;
}
void SCIPInterface::SetSolution(SCIP_SOL* solution) {
objective_value_ = SCIPgetSolOrigObj(scip_, solution);
VLOG(1) << "objective=" << objective_value_;
for (int i = 0; i < solver_->variables_.size(); ++i) {
MPVariable* const var = solver_->variables_[i];
const int var_index = var->index();
const double val =
SCIPgetSolVal(scip_, solution, scip_variables_[var_index]);
var->set_solution_value(val);
VLOG(3) << var->name() << "=" << val;
}
}
absl::optional<MPSolutionResponse> SCIPInterface::DirectlySolveProto(
const MPModelRequest& request) {
// ScipSolveProto doesn't solve concurrently.
@@ -768,22 +747,6 @@ absl::optional<MPSolutionResponse> SCIPInterface::DirectlySolveProto(
return response;
}
int SCIPInterface::SolutionCount() { return SCIPgetNSols(scip_); }
bool SCIPInterface::NextSolution() {
// Make sure we have successfully solved the problem and not modified it.
if (!CheckSolutionIsSynchronizedAndExists()) {
return false;
}
if (current_solution_index_ + 1 >= SolutionCount()) {
return false;
}
current_solution_index_++;
SCIP_SOL** all_solutions = SCIPgetSols(scip_);
SetSolution(all_solutions[current_solution_index_]);
return true;
}
int64 SCIPInterface::iterations() const {
// NOTE(user): As of 2018-12 it doesn't run in the stubby server, and is
// a specialized call, so it's ok to crash if the status is broken.
@@ -838,15 +801,15 @@ void SCIPInterface::SetPrimalTolerance(double value) {
// SCIP automatically updates numerics/lpfeastol if the primal tolerance is
// tighter. Doing that it unconditionally logs this modification to stderr. By
// setting numerics/lpfeastol first we avoid this unwanted log.
double current_lpfeastol = 0.0;
CHECK_EQ(SCIP_OKAY,
SCIPgetRealParam(scip_, "numerics/lpfeastol", &current_lpfeastol));
if (value < current_lpfeastol) {
// See the NOTE on SetRelativeMipGap().
const auto status =
SCIP_TO_STATUS(SCIPsetRealParam(scip_, "numerics/lpfeastol", value));
if (status_.ok()) status_ = status;
}
// double current_lpfeastol = 0.0;
// CHECK_EQ(SCIP_OKAY,
// SCIPgetRealParam(scip_, "numerics/lpfeastol", &current_lpfeastol));
// if (value < current_lpfeastol) {
// // See the NOTE on SetRelativeMipGap().
// const auto status =
// SCIP_TO_STATUS(SCIPsetRealParam(scip_, "numerics/lpfeastol", value));
// if (status_.ok()) status_ = status;
// }
// See the NOTE on SetRelativeMipGap().
const auto status =
SCIP_TO_STATUS(SCIPsetRealParam(scip_, "numerics/feastol", value));