I fixed a few here, but there are lots more. They light up if you build with clang.

--- i/include/numerics/type_n_tensor.h
+++ w/include/numerics/type_n_tensor.h
@@ -67,7 +67,7 @@ public:
   /**
    * Return a proxy for the \f$ i^{th} \f$ slice of the tensor.
    */
-  const TypeNTensor<N-1,T> slice (const unsigned int i) const
+  const TypeNTensor<N-1,T> slice (const unsigned int /* i */) const
     { return TypeNTensor<N-1,T>(); }
 
   /**
@@ -166,14 +166,14 @@ public:
    * @returns \p true if this tensor is "less"
    * than another.  Useful for sorting.
    */
-  bool operator < (const TypeNTensor<N,T>& rhs) const
+  bool operator < (const TypeNTensor<N,T>& /* rhs */) const
     { return false; }
 
   /**
    * @returns \p true if this tensor is "greater"
    * than another.
    */
-  bool operator > (const TypeNTensor<N,T>& rhs) const
+  bool operator > (const TypeNTensor<N,T>& /* rhs */) const
     { return false; }
 
   /**