LinearIterationSteps are now Preconditioners

[[Imported from SVN: r11959]]

dune/solvers/iterationsteps/lineariterationstep.hh

@@ -6,11 +6,16 @@
 #include <dune/common/bitsetvector.hh>
 #include <dune/common/shared_ptr.hh>
 
+#include <dune/solvers/common/preconditioner.hh>
+
 #include "iterationstep.hh"
 
 //! Base class for iteration steps being called by an iterative linear solver
 template<class MatrixType, class VectorType, class BitVectorType = Dune::BitSetVector<VectorType::block_type::dimension> >
-class LinearIterationStep : public IterationStep<VectorType, BitVectorType>
+class LinearIterationStep : public IterationStep<VectorType, BitVectorType>,
+                            public Dune::Solvers::Preconditioner<MatrixType,
+                                                                 VectorType,
+                                                                 BitVectorType>
 {
 public:
     
@@ -33,6 +38,11 @@ public:
         rhs_     = &rhs;
         mat_     = Dune::stackobject_to_shared_ptr(mat);
     }
+
+    //! Set linear operator
+    virtual void setMatrix(const MatrixType& mat) {
+        mat_     = Dune::stackobject_to_shared_ptr(mat);
+    }
     
     //! Do the actual iteration
     virtual void iterate() = 0;
@@ -59,6 +69,15 @@ public:
             DUNE_THROW(SolverError, "Iteration step has no matrix");
 #endif
     }
+
+    virtual void apply(VectorType& x, const VectorType& r)
+    {
+        x = 0;
+        this->x_ = &x;
+        rhs_     = &r;
+        iterate();
+        x = getSol();
+    }
     
     //! The container for the right hand side
     const VectorType* rhs_;