HighsSimplexStats struct gives data about last simplex solve

ERGO-Code · Nov 28, 2024 · 258e8c0 · 258e8c0
1 parent 9fdc611
commit 258e8c0
Show file tree

Hide file tree

Showing 6 changed files with 56 additions and 31 deletions.
diff --git a/check/TestLpSolvers.cpp b/check/TestLpSolvers.cpp
@@ -644,18 +644,38 @@ TEST_CASE("standard-form-lp", "[highs_lp_solver]") {
 }
 
 TEST_CASE("simplex-stats", "[highs_lp_solver]") {
-   HighsStatus return_status;
+  HighsStatus return_status;
 
   Highs h;
-  //  h.setOptionValue("output_flag", dev_run);
-  std::string model_file =
-    std::string(HIGHS_DIR) + "/check/instances/adlittle.mps";
-  REQUIRE(h.readModel(model_file)  == HighsStatus::kOk);
   const HighsSimplexStats& simplex_stats = h.getSimplexStats();
-  simplex_stats.report(stdout);
-  h.reportSimplexStats(stdout);
-  REQUIRE(h.run()  == HighsStatus::kOk);
-  simplex_stats.report(stdout);
-  h.reportSimplexStats(stdout);
-
+  h.setOptionValue("output_flag", dev_run);
+  std::string model_file =
+      std::string(HIGHS_DIR) + "/check/instances/adlittle.mps";
+  REQUIRE(h.readModel(model_file) == HighsStatus::kOk);
+
+  REQUIRE(h.run() == HighsStatus::kOk);
+  REQUIRE(simplex_stats.valid);
+  REQUIRE(simplex_stats.iteration_count == 0);
+  REQUIRE(simplex_stats.num_invert == 1);
+  REQUIRE(simplex_stats.last_invert_num_el > 0);
+  REQUIRE(simplex_stats.last_factored_basis_num_el > 0);
+  REQUIRE(simplex_stats.col_aq_density == 0);
+  REQUIRE(simplex_stats.row_ep_density == 0);
+  REQUIRE(simplex_stats.row_ap_density == 0);
+  REQUIRE(simplex_stats.row_DSE_density == 0);
+  if (dev_run) h.reportSimplexStats(stdout);
+
+  h.clearSolver();
+  h.setOptionValue("presolve", kHighsOffString);
+  REQUIRE(h.run() == HighsStatus::kOk);
+  REQUIRE(simplex_stats.valid);
+  REQUIRE(simplex_stats.iteration_count > 0);
+  REQUIRE(simplex_stats.num_invert > 0);
+  REQUIRE(simplex_stats.last_invert_num_el > 0);
+  REQUIRE(simplex_stats.last_factored_basis_num_el > 0);
+  REQUIRE(simplex_stats.col_aq_density > 0);
+  REQUIRE(simplex_stats.row_ep_density > 0);
+  REQUIRE(simplex_stats.row_ap_density > 0);
+  REQUIRE(simplex_stats.row_DSE_density > 0);
+  if (dev_run) h.reportSimplexStats(stdout);
 }
diff --git a/src/Highs.h b/src/Highs.h
@@ -1216,8 +1216,12 @@ class Highs {
 
   // Start of advanced methods for HiGHS MIP solver
 
-  const HighsSimplexStats& getSimplexStats() const { return ekk_instance_.getSimplexStats(); }
-  void reportSimplexStats(FILE* file) const { ekk_instance_.reportSimplexStats(file); }
+  const HighsSimplexStats& getSimplexStats() const {
+    return ekk_instance_.getSimplexStats();
+  }
+  void reportSimplexStats(FILE* file) const {
+    ekk_instance_.reportSimplexStats(file);
+  }
 
   /**
    * @brief Get the hot start basis data from the most recent simplex

diff --git a/src/lp_data/HStruct.h b/src/lp_data/HStruct.h
@@ -164,9 +164,8 @@ struct HighsSimplexStats {
   double row_ep_density;
   double row_ap_density;
   double row_DSE_density;
-  void report(FILE* file) const;
-  void clear();
+  void report(FILE* file, const std::string message = "") const;
+  void initialise(const HighsInt iteration_count_ = 0);
 };
 
-
 #endif /* LP_DATA_HSTRUCT_H_ */
diff --git a/src/simplex/HApp.h b/src/simplex/HApp.h
@@ -112,9 +112,8 @@ inline HighsStatus solveLpSimplex(HighsLpSolverObject& solver_object) {
   // return
   resetModelStatusAndHighsInfo(solver_object);
 
-  // Clear the simplex stats
-  ekk_instance.clearSimplexStats();
-  ekk_instance.simplex_stats_.iteration_count = -ekk_instance.iteration_count_;
+  // Initialise the simplex stats
+  ekk_instance.initialiseSimplexStats();
 
   // Assumes that the LP has a positive number of rows, since
   // unconstrained LPs should be solved in solveLp

diff --git a/src/simplex/HEkk.cpp b/src/simplex/HEkk.cpp
@@ -296,7 +296,7 @@ void HEkk::invalidate() {
   assert(!this->status_.is_permuted);
   this->status_.initialised_for_solve = false;
   this->invalidateBasisMatrix();
-  this->simplex_stats_.clear();
+  this->simplex_stats_.initialise();
 }
 
 void HEkk::invalidateBasisMatrix() {
@@ -3509,7 +3509,8 @@ HighsStatus HEkk::returnFromEkkSolve(const HighsStatus return_status) {
   simplex_stats_.iteration_count += iteration_count_;
   //  simplex_stats_.num_invert is incremented internally
   simplex_stats_.last_invert_num_el = simplex_nla_.factor_.invert_num_el;
-  simplex_stats_.last_factored_basis_num_el = simplex_nla_.factor_.basis_matrix_num_el;
+  simplex_stats_.last_factored_basis_num_el =
+      simplex_nla_.factor_.basis_matrix_num_el;
   simplex_stats_.col_aq_density = analysis_.col_aq_density;
   simplex_stats_.row_ep_density = analysis_.row_ep_density;
   simplex_stats_.row_ap_density = analysis_.row_ap_density;
@@ -4420,23 +4421,24 @@ void HEkk::unitBtranResidual(const HighsInt row_out, const HVector& row_ep,
   }
 }
 
-void HighsSimplexStats::report(FILE* file) const {
-  fprintf(file, "\nSimplex stats\n");
+void HighsSimplexStats::report(FILE* file, std::string message) const {
+  fprintf(file, "\nSimplex stats: %s\n", message.c_str());
   fprintf(file, "   valid                      = %d\n", this->valid);
   fprintf(file, "   iteration_count            = %d\n", this->iteration_count);
   fprintf(file, "   num_invert                 = %d\n", this->num_invert);
-  fprintf(file, "   last_invert_num_el         = %d\n", this->last_invert_num_el);
-  fprintf(file, "   last_factored_basis_num_el = %d\n", this->last_factored_basis_num_el);
+  fprintf(file, "   last_invert_num_el         = %d\n",
+          this->last_invert_num_el);
+  fprintf(file, "   last_factored_basis_num_el = %d\n",
+          this->last_factored_basis_num_el);
   fprintf(file, "   col_aq_density             = %g\n", this->col_aq_density);
   fprintf(file, "   row_ep_density             = %g\n", this->row_ep_density);
   fprintf(file, "   row_ap_density             = %g\n", this->row_ap_density);
   fprintf(file, "   row_DSE_density            = %g\n", this->row_DSE_density);
-
 }
 
-void HighsSimplexStats::clear() {
+void HighsSimplexStats::initialise(const HighsInt iteration_count_) {
   valid = false;
-  iteration_count = 0;
+  iteration_count = -iteration_count_;
   num_invert = 0;
   last_invert_num_el = 0;
   last_factored_basis_num_el = 0;

diff --git a/src/simplex/HEkk.h b/src/simplex/HEkk.h
@@ -157,8 +157,10 @@ class HEkk {
                            const vector<double>& rowUpper);
 
   const HighsSimplexStats& getSimplexStats() const { return simplex_stats_; }
-  void clearSimplexStats() { simplex_stats_.clear(); }
-  void reportSimplexStats(FILE* file) const { simplex_stats_.report(file); }
+  void initialiseSimplexStats() { simplex_stats_.initialise(iteration_count_); }
+  void reportSimplexStats(FILE* file, const std::string message = "") const {
+    simplex_stats_.report(file, message);
+  }
 
   // Make this private later
   void chooseSimplexStrategyThreads(const HighsOptions& options,
@@ -175,7 +177,6 @@ class HEkk {
       const std::string message, const HighsInt alt_debug_level = -1) const;
   bool debugNlaScalingOk(const HighsLp& lp) const;
 
-
   // Data members
   HighsCallback* callback_;
   HighsOptions* options_;