Resize abstraction for matrices and vectors

src/amdis/common/Resize.hpp

+#pragma once
+
+#include <dune/common/typeutilities.hh>
+
+#include <amdis/common/ConceptsBase.hpp>
+#include <amdis/common/Logical.hpp>
+
+namespace AMDiS
+{
+  namespace Concepts
+  {
+    namespace Definition
+    {
+      struct VectorResizable
+      {
+        template <class V>
+        auto requires_(V const& vec, Dune::PriorityTag<2>) -> decltype( const_cast<V&>(vec).resize(0u), 0);
+
+        template <class V>
+        auto requires_(V const& vec, Dune::PriorityTag<1>) -> decltype( const_cast<V&>(vec).change_dim(0u), 0);
+      };
+
+      struct MatrixResizable
+      {
+        template <class M>
+        auto requires_(M const& mat, Dune::PriorityTag<3>) -> decltype( const_cast<M&>(mat).resize(0u,0u), 0);
+
+        template <class M>
+        auto requires_(M const& mat, Dune::PriorityTag<2>) -> decltype( const_cast<M&>(mat).change_dim(0u,0u), 0);
+
+        template <class M>
+        auto requires_(M const& mat, Dune::PriorityTag<1>) -> decltype( const_cast<M&>(mat).setSize(0u,0u), 0);
+      };
+    }
+
+    /// Checks whether a vector can be resized by various resize methods
+    template <class Vector>
+    using VectorResizable_t = bool_t<models<Definition::VectorResizable(Vector, Dune::PriorityTag<42>)> >;
+
+    /// Checks whether a matrix can be resized by various resize methods
+    template <class Matrix>
+    using MatrixResizable_t = bool_t<models<Definition::MatrixResizable(Matrix, Dune::PriorityTag<42>)> >;
+
+  } // end namespace Concepts
+
+#ifdef DOXYGEN
+  /// \brief Uniform vector resize, using either vector.resize() or vector.change_dim()
+  template <class Vector>
+  void resize(Vector& vec, std::size_t size);
+
+  /// \brief Uniform matrix resize, using either matrix.resize(), matrix.setSize() or matrix.change_dim()
+  template <class Matrix>
+  void resize(Matrix& mat, std::size_t r, std::size_t c);
+#else
+
+  namespace Impl
+  {
+    template <class Vector,
+      class = void_t<decltype(std::declval<Vector&>().resize(0u))> >
+    void resize_impl(Vector& vec, std::size_t size, Dune::PriorityTag<2>)
+    {
+      vec.resize(size);
+    }
+
+    template <class Vector,
+      class = void_t<decltype(std::declval<Vector&>().change_dim(0u))> >
+    void resize_impl(Vector& vec, std::size_t size, Dune::PriorityTag<1>)
+    {
+      vec.change_dim(size);
+    }
+
+    template <class Vector>
+    void resize_impl(Vector& /*vec*/, std::size_t /*size*/, Dune::PriorityTag<0>)
+    {
+      /* do nothing */
+    }
+  }
+
+  template <class Vector>
+  void resize(Vector& vec, std::size_t size)
+  {
+    Impl::resize_impl(vec, size, Dune::PriorityTag<42>{});
+  }
+
+
+  namespace Impl
+  {
+    template <class Matrix,
+      class = void_t<decltype(std::declval<Matrix&>().resize(0u,0u))> >
+    void resize_impl(Matrix& mat, std::size_t rows, std::size_t cols, Dune::PriorityTag<3>)
+    {
+      mat.resize(rows, cols);
+    }
+
+    template <class Matrix,
+      class = void_t<decltype(std::declval<Matrix&>().change_dim(0u,0u))> >
+    void resize_impl(Matrix& mat, std::size_t rows, std::size_t cols, Dune::PriorityTag<2>)
+    {
+      mat.change_dim(rows, cols);
+    }
+
+    template <class Matrix,
+      class = void_t<decltype(std::declval<Matrix&>().setSize(0u,0u))> >
+    void resize_impl(Matrix& mat, std::size_t rows, std::size_t cols, Dune::PriorityTag<1>)
+    {
+      mat.setSize(rows, cols);
+    }
+
+    template <class Matrix>
+    void resize_impl(Matrix& /*mat*/, std::size_t /*rows*/, std::size_t /*cols*/, Dune::PriorityTag<0>)
+    {
+      /* do nothing */
+    }
+  }
+
+  template <class Matrix>
+  void resize(Matrix& mat, std::size_t rows, std::size_t cols)
+  {
+    Impl::resize_impl(mat, rows, cols, Dune::PriorityTag<42>{});
+  }
+
+#endif
+
+} // end namespace AMDiS

test/CMakeLists.txt

@@ -55,6 +55,9 @@ dune_add_test(SOURCES ProblemStatTest.cpp
 dune_add_test(SOURCES RangeTypeTest.cpp
   LINK_LIBRARIES amdis)
 
+dune_add_test(SOURCES ResizeTest.cpp
+  LINK_LIBRARIES amdis)
+
 dune_add_test(SOURCES StringTest.cpp
   LINK_LIBRARIES amdis)
 

test/ResizeTest.cpp

+#include <amdis/AMDiS.hpp>
+#include <amdis/common/Resize.hpp>
+
+using namespace AMDiS;
+
+struct Vec1 { void resize(std::size_t) {} };
+struct Vec2 { void change_dim(std::size_t) {} };
+struct Vec3
+{
+  void resize(std::size_t) {}
+  void change_dim(std::size_t) {}
+};
+
+struct Mat1 { void resize(std::size_t,std::size_t) {} };
+struct Mat2 { void change_dim(std::size_t,std::size_t) {} };
+struct Mat3 { void setSize(std::size_t,std::size_t) {} };
+struct Mat4
+{
+  void resize(std::size_t,std::size_t) {}
+  void change_dim(std::size_t,std::size_t) {}
+  void setSize(std::size_t,std::size_t) {}
+};
+
+struct NotResizable {};
+
+int main(int argc, char** argv)
+{
+  AMDiS::init(argc, argv);
+
+  Vec1 vec1;
+  Vec2 vec2;
+  Vec3 vec3;
+
+  resize(vec1, 1);
+  resize(vec2, 1);
+  resize(vec3, 1);
+
+  static_assert(Concepts::VectorResizable_t<Vec1>::value, "");
+  static_assert(Concepts::VectorResizable_t<Vec2>::value, "");
+  static_assert(Concepts::VectorResizable_t<Vec3>::value, "");
+
+  Mat1 mat1;
+  Mat2 mat2;
+  Mat3 mat3;
+  Mat4 mat4;
+
+  resize(mat1,1,1);
+  resize(mat2,1,1);
+  resize(mat3,1,1);
+  resize(mat4,1,1);
+
+  static_assert(Concepts::MatrixResizable_t<Mat1>::value, "");
+  static_assert(Concepts::MatrixResizable_t<Mat2>::value, "");
+  static_assert(Concepts::MatrixResizable_t<Mat3>::value, "");
+  static_assert(Concepts::MatrixResizable_t<Mat4>::value, "");
+
+  NotResizable notResizable;
+  resize(notResizable,1);
+  resize(notResizable,1,1);
+
+  static_assert(not Concepts::VectorResizable_t<NotResizable>::value, "");
+  static_assert(not Concepts::MatrixResizable_t<NotResizable>::value, "");
+
+  AMDiS::finalize();
+  return 0;
+}