BUG: scaleFactor for fieldValue function-objects is 'sticky' (issue #331)

- if set in a dictionary and later removed, the intermediate value is
  retained rather than reverting to a normal default value.

- same applies for a few other function objects and their variables

src/functionObjects/field/PecletNo/PecletNo.C

@@ -157,7 +157,7 @@ Foam::functionObjects::PecletNo::~PecletNo()
 
 bool Foam::functionObjects::PecletNo::read(const dictionary& dict)
 {
-    dict.readIfPresent("rho", rhoName_);
+    rhoName_ = dict.lookupOrDefault<word>("rho", "rho");
 
     return true;
 }

src/functionObjects/field/blendingFactor/blendingFactor.C

@@ -117,8 +117,13 @@ bool Foam::functionObjects::blendingFactor::read(const dictionary& dict)
     writeFile::read(dict);
 
     phiName_ = dict.lookupOrDefault<word>("phi", "phi");
-    dict.readIfPresent("tolerance", tolerance_);
-    if ((tolerance_ < 0) || (tolerance_ > 1))
+
+    tolerance_ = 0.001;
+    if
+    (
+        dict.readIfPresent("tolerance", tolerance_)
+     && (tolerance_ < 0 || tolerance_ > 1)
+    )
     {
         FatalErrorInFunction
             << "tolerance must be in the range 0 to 1.  Supplied value: "

src/functionObjects/field/fieldValues/fieldValue/fieldValue.C

@@ -97,7 +97,7 @@ bool Foam::functionObjects::fieldValue::read(const dictionary& dict)
 
     dict.lookup("fields") >> fields_;
     dict.lookup("writeFields") >> writeFields_;
-    dict.readIfPresent("scaleFactor", scaleFactor_);
+    scaleFactor_ = dict.lookupOrDefault<scalar>("scaleFactor", 1.0);
 
     return true;
 }

src/functionObjects/field/fieldValues/fieldValue/fieldValue.H

@@ -70,7 +70,7 @@ protected:
 
     // Protected data
 
-        //- Optional scale value
+        //- Optional scaling factor
         scalar scaleFactor_;
 
         //- Construction dictionary

src/functionObjects/field/fluxSummary/fluxSummary.C

@@ -616,9 +616,9 @@ bool Foam::functionObjects::fluxSummary::read(const dictionary& dict)
     writeFile::read(dict);
 
     mode_ = modeTypeNames_.read(dict.lookup("mode"));
-    phiName_= dict.lookupOrDefault<word>("phi", "phi");
-    dict.readIfPresent("scaleFactor", scaleFactor_);
-    dict.readIfPresent("tolerance", tolerance_);
+    phiName_ = dict.lookupOrDefault<word>("phi", "phi");
+    scaleFactor_ = dict.lookupOrDefault<scalar>("scaleFactor", 1.0);
+    tolerance_   = dict.lookupOrDefault<scalar>("tolerance", 0.8);
 
     // Initialise with capacity of 10 faceZones
     DynamicList<vector> refDir(10);

src/functionObjects/field/pressure/pressure.C

@@ -232,8 +232,8 @@ bool Foam::functionObjects::pressure::read(const dictionary& dict)
 {
     fieldExpression::read(dict);
 
-    dict.readIfPresent("U", UName_);
-    dict.readIfPresent("rho", rhoName_);
+    UName_   = dict.lookupOrDefault<word>("U", "U");
+    rhoName_ = dict.lookupOrDefault<word>("rho", "rho");
 
     if (rhoName_ == "rhoInf")
     {