Merge remote-tracking branch 'origin/master' into feature/pybind11-v2.2.1

__init__.py

+from .. import common
+
 from ._istl import *

_istl.cc

@@ -9,17 +9,34 @@
 
 #include <dune/corepy/istl/bcrsmatrix.hh>
 #include <dune/corepy/istl/bvector.hh>
+#include <dune/corepy/istl/operators.hh>
+#include <dune/corepy/istl/preconditioners.hh>
+#include <dune/corepy/istl/solvers.hh>
 
 #include <dune/corepy/pybind11/pybind11.h>
 
 PYBIND11_MODULE( _istl, module )
 {
-  Dune::CorePy::registerBCRSMatrix< Dune::BCRSMatrix< Dune::FieldMatrix< double, 1, 1 > > >( module );
-  Dune::CorePy::registerBlockVector< Dune::BlockVector< Dune::FieldVector< double, 1 > > >( module );
-
   // export solver category
   pybind11::enum_< Dune::SolverCategory::Category > solverCategory( module, "SolverCategory" );
   solverCategory.value( "sequential", Dune::SolverCategory::sequential );
   solverCategory.value( "nonoverlapping", Dune::SolverCategory::nonoverlapping );
   solverCategory.value( "overlapping", Dune::SolverCategory::overlapping );
+
+  // export block vector with block size 1
+  typedef Dune::BlockVector< Dune::FieldVector< double, 1 > > Vector;
+  Dune::CorePy::registerBlockVector< Vector >( module );
+
+  // export linear operator, preconditioners, and solvers for blockvectors with block size 1
+  pybind11::class_< Dune::LinearOperator< Vector, Vector > > clsLinearOperator( module, "LinearOperator" );
+  Dune::CorePy::registerLinearOperator( clsLinearOperator );
+  Dune::CorePy::registerPreconditioners( module, clsLinearOperator );
+  Dune::CorePy::registerSolvers( module, clsLinearOperator );
+
+  // export BCRS matrix with block size 1x1
+  typedef Dune::BCRSMatrix< Dune::FieldMatrix< double, 1, 1 > > Matrix;
+  Dune::CorePy::registerBCRSMatrix< Matrix >( module );
+
+  // export matrix-based preconditioners for BCRS matrix with block size 1x1
+  Dune::CorePy::registerMatrixPreconditioners< Matrix >( module, clsLinearOperator );
 }