--- a/src/modules/bugs/functions/IfElse.h
+++ b/src/modules/bugs/functions/IfElse.h
@@ -23,6 +23,10 @@
     IfElse ();
     double evaluate(std::vector<double const *> const &args) const;
     bool isDiscreteValued(std::vector<bool> const &mask) const;
+    bool isScale(std::vector<bool> const &mask, 
+		 std::vector<bool> const &fixed) const;
+    bool isLinear(std::vector<bool> const &mask, 
+		  std::vector<bool> const &fixed) const;
 };
 
 }}