Fixes #1995. Setting a value for discrete resets the percentile

src/OSPSuite.Core/Domain/Formulas/DiscreteDistributionFormula.cs

@@ -14,12 +14,12 @@ protected override double CalculateFor(IReadOnlyList<IObjectReference> usedObjec
 
       public override double CalculatePercentileForValue(double value, IUsingFormula refObject)
       {
-         return value < Mean(refObject) ? 0 : 0.5; 
+         return 0.5; 
       }
 
       public override double CalculateValueFromPercentile(double percentile, IUsingFormula refObject)
       {
-         return percentile >= 0.5 ? Mean(refObject) : 0; 
+         return Mean(refObject); 
       }
 
       public override double ProbabilityDensityFor(double value, IUsingFormula refObject)

src/OSPSuite.Core/Domain/WithExtensions.cs

@@ -14,13 +14,8 @@ public static T WithDimension<T>(this T withDimension, IDimension dimension) whe
       }
 
       public static T WithValue<T>(this T withValue, double value) where T : IWithValue
-      {
-         //A using formula for which no formula is defined? We create a constant formula
-         if (withValue is IUsingFormula usingFormula && usingFormula.Formula == null)
-            usingFormula.Formula = new ConstantFormula(value);
-         else
-            withValue.Value = value;
-
+      { 
+         withValue.Value = value;
          return withValue;
       }
 

tests/OSPSuite.Core.Tests/Domain/DistributionFormulaFactorySpecs.cs

@@ -91,9 +91,7 @@ protected override void Because()
       [Observation]
       public void distributed_parameter_should_return_correct_value()
       {
-         var distr = new DiscreteDistributionFormula();
-
-         _distributedParam.Value.ShouldBeEqualTo(distr.CalculateValueFromPercentile(_distributedParam.Percentile, _distributedParam), 1e-5);
+         _distributedParam.Value.ShouldBeEqualTo(_distributedParam.MeanParameter.Value);
       }
    }