Can now select whether to minimize or maximize objective.

Can now specify in driver whether the objective function should be maximized or minimized.

FieldOpt/GTest/Utilities/driver/driver.json

@@ -5,6 +5,7 @@
     },
     "Optimizer": {
         "Type": "Compass",
+        "Mode": "Maximize",
         "Parameters": {
             "MaxEvaluations": 10,
             "InitialStepLength": 50.0,

FieldOpt/GTest/Utilities/settings/test_settings_optimizer.cpp

@@ -53,6 +53,10 @@ TEST_F(OptimizerSettingsTest, Type) {
     EXPECT_EQ(Optimizer::OptimizerType::Compass, settings_.optimizer()->type());
 }
 
+TEST_F(OptimizerSettingsTest, Mode) {
+    EXPECT_EQ(Optimizer::OptimizerMode::Maximize, settings_.optimizer()->mode());
+}
+
 TEST_F(OptimizerSettingsTest, Parameters) {
     Optimizer::Parameters params = settings_.optimizer()->parameters();
     EXPECT_EQ(10, params.max_evaluations);

FieldOpt/Optimization/optimizer.cpp

@@ -41,22 +41,35 @@ Optimizer::Optimizer(Utilities::Settings::Optimizer *settings, Case *base_case,
     case_handler_ = new CaseHandler(tentative_best_case_);
     constraint_handler_ = new Constraints::ConstraintHandler(settings->constraints(), variables);
     iteration_ = 0;
+    mode_ = settings->mode();
 }
 
 bool Optimizer::betterCaseFoundLastEvaluation()
 {
     foreach (Case* c, case_handler_->RecentlyEvaluatedCases()) {
-        if (c->objective_function_value() > tentative_best_case_->objective_function_value())
-            return true;
+        if (mode_ == Utilities::Settings::Optimizer::OptimizerMode::Maximize) {
+            if (c->objective_function_value() > tentative_best_case_->objective_function_value())
+                return true;
+        }
+        else if (mode_ == Utilities::Settings::Optimizer::OptimizerMode::Minimize) {
+            if (c->objective_function_value() < tentative_best_case_->objective_function_value())
+                return true;
+        }
     }
     return false;
 }
 
 void Optimizer::applyNewTentativeBestCase()
 {
     foreach (Case* c, case_handler_->RecentlyEvaluatedCases()) {
-        if (c->objective_function_value() > tentative_best_case_->objective_function_value())
-            tentative_best_case_ = c;
+        if (mode_ == Utilities::Settings::Optimizer::OptimizerMode::Maximize) {
+            if (c->objective_function_value() > tentative_best_case_->objective_function_value())
+                tentative_best_case_ = c;
+        }
+        else if (mode_ == Utilities::Settings::Optimizer::OptimizerMode::Minimize) {
+            if (c->objective_function_value() < tentative_best_case_->objective_function_value())
+                tentative_best_case_ = c;
+        }
     }
 }
 

FieldOpt/Optimization/optimizer.h

@@ -125,6 +125,7 @@ class Optimizer
     Constraints::ConstraintHandler *constraint_handler_; //!< All constraints defined for the optimization.
     int max_evaluations_; //!< Maximum number of objective function evaluations allowed before terminating.
     int iteration_; //!< The current iteration.
+    ::Utilities::Settings::Optimizer::OptimizerMode mode_; //!< The optimization mode, i.e. whether the objective function should be maximized or minimized.
 };
 
 }

FieldOpt/Utilities/settings/README.md

@@ -224,13 +224,15 @@ The optimizer section contains optimizer specific settings and parameters. The r
 ```
 "Optimizer": {
 	"Type": string,
+	"Mode": "Maximize",
 	"Parameters": { ... },
 	"Objective": { ... },
 	"Constraints": [ {...}, {...}, ... ]
 }
 ```
 
 * `Type` denotes which optmizer is to be used. Currently the only implemented algorithm is `Compass`.
+* `Mode` specifies whether the objective function should be `Maximize`d or `Minimize`d.
 * `Parameters` holds the optimization algorithm-specific parameters. The structure is shown below.
 * `Objective` specifies the objective function to be used by the optimization algorithm. The structure is shown below.
 * `Constraints` is an array of objects defining the constraints to be applied to the algorithm/variables. The structure of each constraint object is shown below.

FieldOpt/Utilities/settings/optimizer.cpp

@@ -44,6 +44,16 @@ Optimizer::Optimizer(QJsonObject json_optimizer)
         type_ = OptimizerType::Compass;
     else throw OptimizerTypeNotRecognizedException("The optimizer type " + type.toStdString() + " was not recognized.");
 
+    // Optimizer mode
+    if (json_optimizer.contains("Mode")) {
+        QString mode = json_optimizer["Mode"].toString();
+        if (QString::compare(mode, "Minimize", Qt::CaseInsensitive) == 0)
+            mode_ = OptimizerMode::Minimize;
+        else if (QString::compare(mode, "Maximize", Qt::CaseInsensitive) == 0)
+            mode_ = OptimizerMode::Maximize;
+        else throw UnableToParseOptimizerSectionException("Did not recognize optimizer Mode setting.");
+    } else throw UnableToParseOptimizerSectionException("Optimizer Mode keyword must be specified.");
+
     // Optimizer parameters
     try {
         parameters_.max_evaluations = json_parameters["MaxEvaluations"].toInt();

FieldOpt/Utilities/settings/optimizer.h

@@ -45,6 +45,7 @@ class Optimizer
 
 public:
     enum OptimizerType { Compass };
+    enum OptimizerMode { Maximize, Minimize };
     enum ConstraintType { BHP, Rate, SplinePoints };
     enum ConstraintWellSplinePointsType { MaxMin, Function};
     enum ObjectiveType { WeightedSum };
@@ -77,6 +78,7 @@ class Optimizer
     };
 
     OptimizerType type() const { return type_; } //!< Get the Optimizer type (e.g. Compass).
+    OptimizerMode mode() const { return mode_; } //!< Get the optimizer mode (maximize/minimize).
     Parameters parameters() const { return parameters_; } //!< Get the optimizer parameters.
     Objective objective() const { return objective_; } //!< Get the optimizer objective function.
     QList<Constraint> *constraints() const { return constraints_; } //!< Get the optimizer constraints.
@@ -87,7 +89,7 @@ class Optimizer
     Parameters parameters_;
     Objective objective_;
     QList<Constraint> *constraints_;
-
+    OptimizerMode mode_;
     Constraint parseSingleConstraint(QJsonObject json_constraint);
 };
 

examples/horzwell_bhp.json

@@ -5,6 +5,7 @@
     },
     "Optimizer": {
         "Type": "Compass",
+        "Mode": "Maximize",
         "Parameters": {
             "MaxEvaluations": 50,
             "InitialStepLength": 100.0,