Fix warning: unused parameter

src/bisection-simpler-example.cc

@@ -31,7 +31,7 @@ class SampleFunctional : public SmallFunctional<2> {
     return y;
   }
 
-  SmallMatrix d2(const SmallVector v) const { return A_; }
+  SmallMatrix d2(const SmallVector) const { return A_; }
 
 private:
   SmallMatrix A_;

src/bisection-simpler-example2-gradient.cc

@@ -37,7 +37,7 @@ class SampleFunctional : public SmallFunctional<dimension> {
     return y;
   }
 
-  SmallMatrix d2(const SmallVector v) const { return A_; }
+  SmallMatrix d2(const SmallVector) const { return A_; }
 
   // extending the interface here
   double directionalDerivative(const SmallVector x,

src/bisection-simpler-example2.cc

@@ -35,7 +35,7 @@ class SampleFunctional : public SmallFunctional<dimension> {
     return y;
   }
 
-  SmallMatrix d2(const SmallVector v) const { return A_; }
+  SmallMatrix d2(const SmallVector) const { return A_; }
 
 private:
   SmallMatrix A_;