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#include "HCheckConfig.h"
#include "Highs.h"
#include "catch.hpp"
const double inf = kHighsInf;
const bool dev_run = false;
const double double_equal_tolerance = 1e-5;
TEST_CASE("HotStart-avgas", "[highs_test_hot_start]") {
std::string filename;
filename = std::string(HIGHS_DIR) + "/check/instances/avgas.mps";
Highs highs;
if (!dev_run) highs.setOptionValue("output_flag", false);
highs.readModel(filename);
const HighsLp& lp = highs.getLp();
const HighsInt num_col = lp.num_col_;
const HighsInt from_col = 0;
const HighsInt to_col = num_col - 1;
vector<double> original_col_lower = lp.col_lower_;
vector<double> original_col_upper = lp.col_upper_;
HotStart hot_start0 = highs.getHotStart();
// Before run() has been called the hot start is not valid
REQUIRE(!hot_start0.valid);
// Get the integer solution to provide bound tightenings
vector<HighsVarType> integrality;
integrality.assign(num_col, HighsVarType::kInteger);
highs.changeColsIntegrality(from_col, to_col, integrality.data());
highs.setOptionValue("output_flag", false);
highs.run();
if (dev_run) highs.setOptionValue("output_flag", true);
vector<double> integer_solution = highs.getSolution().col_value;
// Now restore the original integrality
integrality.assign(num_col, HighsVarType::kContinuous);
highs.changeColsIntegrality(from_col, to_col, integrality.data());
// Solve the continuous problem and get its hot start
highs.run();
if (dev_run) {
highs.setOptionValue("output_flag", true);
highs.setOptionValue("highs_analysis_level", 4);
highs.setOptionValue("log_dev_level", 3);
}
HotStart hot_start1 = highs.getHotStart();
// Invalidate the basis
highs.setBasis();
// Set the integer solution as upper bounds
highs.changeColsBounds(from_col, to_col, original_col_lower.data(),
integer_solution.data());
if (dev_run) printf("\nSolving with bounds (lower, integer solution)\n");
// Use the continuous solution as a hot start
REQUIRE(highs.setHotStart(hot_start0) == HighsStatus::kError);
REQUIRE(highs.setHotStart(hot_start1) == HighsStatus::kOk);
highs.run();
// Cannot use an invalid hot start
REQUIRE(highs.setHotStart(hot_start0) == HighsStatus::kError);
}
TEST_CASE("HotStart-rgn", "[highs_test_hot_start]") {
std::string filename;
filename = std::string(HIGHS_DIR) + "/check/instances/rgn.mps";
Highs highs;
if (!dev_run) highs.setOptionValue("output_flag", false);
highs.readModel(filename);
const HighsLp& lp = highs.getLp();
const HighsInt num_col = lp.num_col_;
const HighsInt from_col = 0;
const HighsInt to_col = num_col - 1;
vector<double> original_col_lower = lp.col_lower_;
vector<double> original_col_upper = lp.col_upper_;
// Get the MIP solution to provide bound tightenings
highs.setOptionValue("output_flag", false);
highs.run();
if (dev_run) highs.setOptionValue("output_flag", true);
vector<double> mip_solution = highs.getSolution().col_value;
// Now remove integrality
vector<HighsVarType> integrality;
integrality.assign(num_col, HighsVarType::kContinuous);
highs.changeColsIntegrality(from_col, to_col, integrality.data());
// Solve the continuous problem and get its hot start
highs.run();
if (dev_run) {
highs.setOptionValue("output_flag", true);
highs.setOptionValue("highs_analysis_level", 4);
highs.setOptionValue("log_dev_level", 3);
}
HotStart hot_start = highs.getHotStart();
// Invalidate the basis
highs.setBasis();
// Set the mip solution as upper bounds
highs.changeColsBounds(from_col, to_col, original_col_lower.data(),
mip_solution.data());
if (dev_run) printf("\nSolving with bounds (lower, mip solution)\n");
// Use the continuous solution as a hot start
REQUIRE(highs.setHotStart(hot_start) == HighsStatus::kOk);
highs.run();
// Add a row
highs.addRow(kHighsZero, kHighsInf, 0, NULL, NULL);
// Cannot use the continuous solution as a hot start now
REQUIRE(highs.setHotStart(hot_start) == HighsStatus::kError);
}
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