ENH: Updated weight field initialisation for fieldValues function object

src/postProcessing/functionObjects/field/fieldValues/cellSource/cellSource.C

@@ -145,23 +145,8 @@ void Foam::fieldValues::cellSource::initialise(const dictionary& dict)
     if (operation_ == opWeightedAverage)
     {
         dict.lookup("weightField") >> weightFieldName_;
-        if
-        (
-            obr().foundObject<volScalarField>(weightFieldName_)
-        )
-        {
         Info<< "    weight field = " << weightFieldName_;
     }
-        else
-        {
-            FatalErrorIn("cellSource::initialise()")
-                << type() << " " << name_ << ": "
-                << sourceTypeNames_[source_] << "(" << sourceName_ << "):"
-                << nl << "    Weight field " << weightFieldName_
-                << " must be a " << volScalarField::typeName
-                << nl << exit(FatalError);
-        }
-    }
 
     Info<< nl << endl;
 }

src/postProcessing/functionObjects/field/fieldValues/cellSource/cellSource.H

@@ -157,7 +157,8 @@ protected:
         template<class Type>
         tmp<Field<Type> > setFieldValues
         (
-            const word& fieldName
+            const word& fieldName,
+            const bool mustGet = false
         ) const;
 
         //- Apply the 'operation' to the values

src/postProcessing/functionObjects/field/fieldValues/cellSource/cellSourceTemplates.C

@@ -45,7 +45,8 @@ bool Foam::fieldValues::cellSource::validField(const word& fieldName) const
 template<class Type>
 Foam::tmp<Foam::Field<Type> > Foam::fieldValues::cellSource::setFieldValues
 (
-    const word& fieldName
+    const word& fieldName,
+    const bool mustGet
 ) const
 {
     typedef GeometricField<Type, fvPatchField, volMesh> vf;
@@ -55,6 +56,20 @@ Foam::tmp<Foam::Field<Type> > Foam::fieldValues::cellSource::setFieldValues
         return filterField(obr_.lookupObject<vf>(fieldName));
     }
 
+    if (mustGet)
+    {
+        FatalErrorIn
+        (
+            "Foam::tmp<Foam::Field<Type> > "
+            "Foam::fieldValues::cellSource::setFieldValues"
+            "("
+                "const word&, "
+                "const bool"
+            ") const"
+        )   << "Field " << fieldName << " not found in database"
+            << abort(FatalError);
+    }
+
     return tmp<Field<Type> >(new Field<Type>(0.0));
 }
 
@@ -125,7 +140,13 @@ bool Foam::fieldValues::cellSource::writeValues(const word& fieldName)
         scalarField V(filterField(mesh().V()));
         combineFields(V);
 
-        scalarField weightField(setFieldValues<scalar>(weightFieldName_));
+        scalarField weightField;
+
+        if (operation_ == opWeightedAverage)
+        {
+            weightField = setFieldValues<scalar>(weightFieldName_, true);
+        }
+
         combineFields(weightField);
 
         if (Pstream::master())

src/postProcessing/functionObjects/field/fieldValues/faceSource/faceSource.C

@@ -284,24 +284,8 @@ void Foam::fieldValues::faceSource::initialise(const dictionary& dict)
     if (operation_ == opWeightedAverage)
     {
         dict.lookup("weightField") >> weightFieldName_;
-        if
-        (
-            obr().foundObject<volScalarField>(weightFieldName_)
-         || obr().foundObject<surfaceScalarField>(weightFieldName_)
-        )
-        {
         Info<< "    weight field = " << weightFieldName_;
     }
-        else
-        {
-            FatalErrorIn("faceSource::initialise()")
-                << type() << " " << name_ << ": "
-                << sourceTypeNames_[source_] << "(" << sourceName_ << "):"
-                << nl << "    Weight field " << weightFieldName_
-                << " must be either a " << volScalarField::typeName << " or "
-                << surfaceScalarField::typeName << nl << exit(FatalError);
-        }
-    }
 
     Info<< nl << endl;
 }

src/postProcessing/functionObjects/field/fieldValues/faceSource/faceSource.H

@@ -200,7 +200,11 @@ protected:
 
         //- Return field values by looking up field name
         template<class Type>
-        tmp<Field<Type> > getFieldValues(const word& fieldName) const;
+        tmp<Field<Type> > getFieldValues
+        (
+            const word& fieldName,
+            const bool mustGet = false
+        ) const;
 
         //- Apply the 'operation' to the values
         template<class Type>

src/postProcessing/functionObjects/field/fieldValues/faceSource/faceSourceTemplates.C

@@ -52,7 +52,8 @@ bool Foam::fieldValues::faceSource::validField(const word& fieldName) const
 template<class Type>
 Foam::tmp<Foam::Field<Type> > Foam::fieldValues::faceSource::getFieldValues
 (
-    const word& fieldName
+    const word& fieldName,
+    const bool mustGet
 ) const
 {
     typedef GeometricField<Type, fvsPatchField, surfaceMesh> sf;
@@ -74,6 +75,20 @@ Foam::tmp<Foam::Field<Type> > Foam::fieldValues::faceSource::getFieldValues
         }
     }
 
+    if (mustGet)
+    {
+        FatalErrorIn
+        (
+            "Foam::tmp<Foam::Field<Type> > "
+            "Foam::fieldValues::faceSource::getFieldValues"
+            "("
+                "const word&, "
+                "const bool"
+            ") const"
+        )   << "Field " << fieldName << " not found in database"
+            << abort(FatalError);
+    }
+
     return tmp<Field<Type> >(new Field<Type>(0));
 }
 
@@ -139,7 +154,13 @@ bool Foam::fieldValues::faceSource::writeValues(const word& fieldName)
     if (ok)
     {
         Field<Type> values(getFieldValues<Type>(fieldName));
-        scalarField weightField(getFieldValues<scalar>(weightFieldName_));
+        scalarField weightField;
+
+        if (operation_ == opWeightedAverage)
+        {
+            weightField = getFieldValues<scalar>(weightFieldName_, true);
+        }
+
         scalarField magSf;
 
         if (surfacePtr_.valid())