message: Adding a comment block to explain the existence of the ComplexSparseMatrix class.
diff: @@ -602,6 +602,15 @@ template<> inline void Swap<SparseMatrix>(SparseMatrix &a, SparseMatrix &b)
  a.Swap(b);
  }
  +/** @brief Specialization of the ComplexOperator built from a pair of
  + Sparse Matrices.
  +
  + The purpose of this specialization is to construct a single
  + SparseMatrix object which is equivalent to the 2x2 block system
  + that the ComplexOperator mimics. The resulting SparseMatrix can
  + then be passed along to solvers which require access to the CSR
  + matrix data such as SuperLU, STRUMPACK, or similar sparse solvers.
  + */
  class ComplexSparseMatrix : public ComplexOperator
  {
  public:
  