Removed HighsOptions::cost_scale

Author: jajhall

highs/lp_data/HighsOptions.h

@@ -400,7 +400,6 @@ struct HighsOptionsStruct {
   bool mps_parser_type_free;
   bool use_warm_start;
   HighsInt keep_n_rows;
-  HighsInt cost_scale_factor;
   HighsInt allowed_matrix_scale_factor;
   HighsInt allowed_cost_scale_factor;
   HighsInt ipx_dualize_strategy;
@@ -561,7 +560,6 @@ struct HighsOptionsStruct {
         mps_parser_type_free(false),
         use_warm_start(true),
         keep_n_rows(0),
-        cost_scale_factor(0),
         allowed_matrix_scale_factor(0),
         allowed_cost_scale_factor(0),
         ipx_dualize_strategy(0),
@@ -1385,11 +1383,6 @@ class HighsOptions : public HighsOptionsStruct {
                             kKeepNRowsDeleteRows, kKeepNRowsKeepRows);
     records.push_back(record_int);
 
-    record_int =
-        new OptionRecordInt("cost_scale_factor", "Scaling factor for costs",
-                            advanced, &cost_scale_factor, -20, 0, 20);
-    records.push_back(record_int);
-
     record_int = new OptionRecordInt(
         "allowed_matrix_scale_factor",
         "Largest power-of-two factor permitted when "
@@ -1401,7 +1394,8 @@ class HighsOptions : public HighsOptionsStruct {
     record_int = new OptionRecordInt(
         "allowed_cost_scale_factor",
         "Largest power-of-two factor permitted when scaling the costs",
-        advanced, &allowed_cost_scale_factor, 0, 0, 20);
+        advanced, &allowed_cost_scale_factor, 0,
+	kDefaultAllowedMatrixPow2Scale, kMaxAllowedMatrixPow2Scale);
     records.push_back(record_int);
 
     record_int = new OptionRecordInt(

highs/simplex/HApp.h

@@ -228,15 +228,6 @@ inline HighsStatus solveLpSimplex(HighsLpSolverObject& solver_object) {
     ekk_instance.undualize();
     assert(!ekk_instance.status_.is_permuted &&
            !ekk_instance.status_.is_dualized);
-    if (options.cost_scale_factor) {
-      double cost_scale_factor = pow(2.0, -options.cost_scale_factor);
-      highsLogDev(options.log_options, HighsLogType::kInfo,
-                  "Objective = %11.4g\n",
-                  cost_scale_factor * ekk_instance.info_.dual_objective_value);
-      ekk_instance.model_status_ = HighsModelStatus::kNotset;
-      return_status = HighsStatus::kError;
-    }
-    //
   } else {
     // Indicate that there is no (current) need to refine the solution
     // by solving the unscaled LP with scaled NLA
@@ -256,15 +247,6 @@ inline HighsStatus solveLpSimplex(HighsLpSolverObject& solver_object) {
       ekk_instance.undualize();
       assert(!ekk_instance.status_.is_permuted &&
              !ekk_instance.status_.is_dualized);
-      //
-      if (options.cost_scale_factor) {
-        double cost_scale_factor = pow(2.0, -options.cost_scale_factor);
-        highsLogDev(
-            options.log_options, HighsLogType::kInfo, "Objective = %11.4g\n",
-            cost_scale_factor * ekk_instance.info_.dual_objective_value);
-        ekk_instance.model_status_ = HighsModelStatus::kNotset;
-        return_status = HighsStatus::kError;
-      }
       if (return_status == HighsStatus::kError) {
         incumbent_lp.moveBackLpAndUnapplyScaling(ekk_lp);
         return returnFromSolveLpSimplex(solver_object, return_status);

highs/simplex/HEkk.cpp

@@ -2663,10 +2663,8 @@ void HEkk::initialiseBound(const SimplexAlgorithm algorithm,
 }
 
 void HEkk::initialiseLpColCost() {
-  double cost_scale_factor = pow(2.0, options_->cost_scale_factor);
   for (HighsInt iCol = 0; iCol < lp_.num_col_; iCol++) {
-    info_.workCost_[iCol] =
-        (HighsInt)lp_.sense_ * cost_scale_factor * lp_.col_cost_[iCol];
+    info_.workCost_[iCol] = HighsInt(lp_.sense_) * lp_.col_cost_[iCol];
     info_.workShift_[iCol] = 0;
   }
 }

highs/simplex/HEkkDual.cpp

@@ -1310,8 +1310,6 @@ void HEkkDual::iterateTasks() {
 }
 
 void HEkkDual::iterationAnalysisData() {
-  double cost_scale_factor =
-      pow(2.0, -ekk_instance_.options_->cost_scale_factor);
   HighsSimplexInfo& info = ekk_instance_.info_;
   analysis->simplex_strategy = info.simplex_strategy;
   analysis->edge_weight_mode = edge_weight_mode;
@@ -1327,7 +1325,7 @@ void HEkkDual::iterationAnalysisData() {
   analysis->edge_weight = 0;
   analysis->primal_delta = delta_primal;
   analysis->primal_step = theta_primal;
-  analysis->dual_step = theta_dual * cost_scale_factor;
+  analysis->dual_step = theta_dual;
   analysis->pivot_value_from_column = alpha_col;
   analysis->pivot_value_from_row = alpha_row;
   analysis->factor_pivot_threshold = info.factor_pivot_threshold;