Added initialization step to ensure that the initialGuess is not internal parameters.

src/Numerics/Optimization/IObjectiveModel.cs

@@ -41,11 +41,11 @@ namespace MathNet.Numerics.Optimization
         /// <summary>
         /// Get the number of calls to function.
         /// </summary>
-        int FunctionEvaluations { get; }
+        int FunctionEvaluations { get; set; }
         /// <summary>
         /// Get the number of calls to jacobian.
         /// </summary>
-        int JacobianEvaluations { get; }
+        int JacobianEvaluations { get; set; }
 
         /// <summary>
         /// Get the degree of freedom.

src/Numerics/Optimization/LevenbergMarquardtMinimizer.cs

@@ -120,6 +120,10 @@ namespace MathNet.Numerics.Optimization
 
             ExitCondition exitCondition = ExitCondition.None;
 
+            // Initialize objective
+            objective.FunctionEvaluations = 0;
+            objective.JacobianEvaluations = 0;
+
             // First, calculate function values and setup variables
             objective.EvaluateFunction(initialGuess);
             var P = objective.Parameters; // current parameters

src/Numerics/Optimization/ObjectiveModels/FittingObjectiveModel.cs

@@ -125,11 +125,11 @@ namespace MathNet.Numerics.Optimization.ObjectiveModels
         /// <summary>
         /// Get the number of calls to function.
         /// </summary>
-        public int FunctionEvaluations { get; private set; }
+        public int FunctionEvaluations { get; set; }
         /// <summary>
         /// Get the number of calls to jacobian.
         /// </summary>
-        public int JacobianEvaluations { get; private set; }
+        public int JacobianEvaluations { get; set; }
 
         /// <summary>
         /// Set or get the desired accuracy order of the numerical jacobian.

src/Numerics/Optimization/TrustRegionDogLegMinimizer.cs

@@ -121,6 +121,10 @@ namespace MathNet.Numerics.Optimization
 
             ExitCondition exitCondition = ExitCondition.None;
 
+            // Initialize objective
+            objective.FunctionEvaluations = 0;
+            objective.JacobianEvaluations = 0;
+
             // First, calculate function values and setup variables
             objective.EvaluateFunction(initialGuess);
             var P = objective.Parameters; // current parameters