fvector.hh

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// -*- tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
// vi: set et ts=4 sw=2 sts=2:
// $Id$
#ifndef DUNE_FVECTOR_HH
#define DUNE_FVECTOR_HH
 
#include <cmath>
#include <cstddef>
#include <cstdlib>
#include <complex>
#include <cstring>
#include <utility>
 
#include <dune/common/std/constexpr.hh>
 
#include "typetraits.hh"
#include "exceptions.hh"
#include "array.hh"
#include "densevector.hh"
#include "static_assert.hh"
#include "unused.hh"
 
namespace Dune {
 
  template< class K, int SIZE > class FieldVector;
  template< class K, int SIZE >
  struct DenseMatVecTraits< FieldVector<K,SIZE> >
  {
    typedef FieldVector<K,SIZE> derived_type;
    typedef Dune::array<K,SIZE> container_type;
    typedef K value_type;
    typedef typename container_type::size_type size_type;
  };
 
  template< class K, int SIZE >
  struct FieldTraits< FieldVector<K,SIZE> >
  {
    typedef typename FieldTraits<K>::field_type field_type;
    typedef typename FieldTraits<K>::real_type real_type;
  };
 
  template<typename C, int SIZE>
  struct IsFieldVectorSizeCorrect
  {
    enum {
      value = true
    };
  };
 
  template<typename T, int SIZE>
  struct IsFieldVectorSizeCorrect<FieldVector<T,SIZE>,SIZE>
  {
    enum {value = true};
  };
 
  template<typename T, int SIZE, int SIZE1>
  struct IsFieldVectorSizeCorrect<FieldVector<T,SIZE1>,SIZE>
  {
    enum {value = false};
  };
 
 
  template< class K, int SIZE >
  class FieldVector :
    public DenseVector< FieldVector<K,SIZE> >
  {
    Dune::array<K,SIZE> _data;
    typedef DenseVector< FieldVector<K,SIZE> > Base;
  public:
    enum {
      dimension = SIZE
    };
 
    typedef typename Base::size_type size_type;
    typedef typename Base::value_type value_type;
 
    FieldVector()
    // Use C++11 unified initialization if available - tends to generate
    // fastest code
#if HAVE_INITIALIZER_LIST
      : _data{}
    {}
#else
    {
      // fall back to library approach - this gives faster code than array placement
      // new. Apart from that, placement new may create problems if K is a complex
      // type. In that case, the default constructor of the _data elements has already
      // been called and may have allocated memory.
      std::fill(_data.begin(),_data.end(),K());
    }
#endif
 
    explicit FieldVector (const K& t)
    {
      fill(t);
    }
 
    FieldVector (const FieldVector & x) : _data(x._data)
    {}
 
    template<class C>
    FieldVector (const DenseVector<C> & x, typename Dune::enable_if<IsFieldVectorSizeCorrect<C,SIZE>::value>::type* dummy=0 )
    {
      DUNE_UNUSED_PARAMETER(dummy);
      // do a run-time size check, for the case that x is not a FieldVector
      assert(x.size() == SIZE);
      for (size_type i = 0; i<SIZE; i++)
        _data[i] = x[i];
    }
 
    template<class K1, int SIZE1>
    explicit FieldVector (const FieldVector<K1,SIZE1> & x)
    {
      dune_static_assert(SIZE1 == SIZE, "FieldVector in constructor has wrong size");
      for (size_type i = 0; i<SIZE; i++)
        _data[i] = x[i];
    }
    using Base::operator=;
 
    DUNE_CONSTEXPR size_type size () const { return vec_size(); }
 
    // make this thing a vector
    DUNE_CONSTEXPR size_type vec_size () const { return SIZE; }
    K & vec_access(size_type i) { return _data[i]; }
    const K & vec_access(size_type i) const { return _data[i]; }
  private:
    void fill(const K& t)
    {
      for (int i=0; i<SIZE; i++) _data[i]=t;
    }
  };
 
  template<class K, int SIZE>
  inline std::istream &operator>> ( std::istream &in,
                                    FieldVector<K, SIZE> &v )
  {
    FieldVector<K, SIZE> w;
    for( typename FieldVector<K, SIZE>::size_type i = 0; i < SIZE; ++i )
      in >> w[ i ];
    if(in)
      v = w;
    return in;
  }
 
#ifndef DOXYGEN
  template< class K >
  struct DenseMatVecTraits< FieldVector<K,1> >
  {
    typedef FieldVector<K,1> derived_type;
    typedef K container_type;
    typedef K value_type;
    typedef size_t size_type;
  };
 
  template<class K>
  class FieldVector<K, 1> :
    public DenseVector< FieldVector<K,1> >
  {
    K _data;
    typedef DenseVector< FieldVector<K,1> > Base;
  public:
    enum {
      dimension = 1
    };
 
    typedef typename Base::size_type size_type;
 
    //===== construction
 
    FieldVector ()
      : _data()
    {}
 
    FieldVector (const K& k) : _data(k) {}
 
    template<class C>
    FieldVector (const DenseVector<C> & x)
    {
      dune_static_assert(((bool)IsFieldVectorSizeCorrect<C,1>::value), "FieldVectors do not match in dimension!");
      assert(x.size() == 1);
      _data = x[0];
    }
 
    FieldVector ( const FieldVector &other )
      : _data( other._data )
    {}
 
    inline FieldVector& operator= (const K& k)
    {
      _data = k;
      return *this;
    }
 
    DUNE_CONSTEXPR size_type size () const { return vec_size(); }
 
    //===== forward methods to container
    DUNE_CONSTEXPR size_type vec_size () const { return 1; }
    K & vec_access(size_type i)
    {
      assert(i == 0);
      return _data;
    }
    const K & vec_access(size_type i) const
    {
      assert(i == 0);
      return _data;
    }
 
    //===== conversion operator
 
    operator K () { return _data; }
 
    operator K () const { return _data; }
  };
 
  /* ----- FV / FV ----- */
  /* not necessary as these operations are already covered via the cast operator */
 
  /* ----- FV / scalar ----- */
 
  template<class K>
  inline FieldVector<K,1> operator+ (const FieldVector<K,1>& a, const K b)
  {
    return a[0]+b;
  }
 
  template<class K>
  inline FieldVector<K,1> operator- (const FieldVector<K,1>& a, const K b)
  {
    return a[0]-b;
  }
 
  template<class K>
  inline FieldVector<K,1> operator* (const FieldVector<K,1>& a, const K b)
  {
    return a[0]*b;
  }
 
  template<class K>
  inline FieldVector<K,1> operator/ (const FieldVector<K,1>& a, const K b)
  {
    return a[0]/b;
  }
 
  template<class K>
  inline bool operator> (const FieldVector<K,1>& a, const K b)
  {
    return a[0]>b;
  }
 
  template<class K>
  inline bool operator>= (const FieldVector<K,1>& a, const K b)
  {
    return a[0]>=b;
  }
 
  template<class K>
  inline bool operator< (const FieldVector<K,1>& a, const K b)
  {
    return a[0]<b;
  }
 
  template<class K>
  inline bool operator<= (const FieldVector<K,1>& a, const K b)
  {
    return a[0]<=b;
  }
 
  template<class K>
  inline bool operator== (const FieldVector<K,1>& a, const K b)
  {
    return a[0]==b;
  }
 
  template<class K>
  inline bool operator!= (const FieldVector<K,1>& a, const K b)
  {
    return a[0]!=b;
  }
 
  /* ----- scalar / FV ------ */
 
  template<class K>
  inline FieldVector<K,1> operator+ (const K a, const FieldVector<K,1>& b)
  {
    return a+b[0];
  }
 
  template<class K>
  inline FieldVector<K,1> operator- (const K a, const FieldVector<K,1>& b)
  {
    return a-b[0];
  }
 
  template<class K>
  inline FieldVector<K,1> operator* (const K a, const FieldVector<K,1>& b)
  {
    return a*b[0];
  }
 
  template<class K>
  inline FieldVector<K,1> operator/ (const K a, const FieldVector<K,1>& b)
  {
    return a/b[0];
  }
 
  template<class K>
  inline bool operator> (const K a, const FieldVector<K,1>& b)
  {
    return a>b[0];
  }
 
  template<class K>
  inline bool operator>= (const K a, const FieldVector<K,1>& b)
  {
    return a>=b[0];
  }
 
  template<class K>
  inline bool operator< (const K a, const FieldVector<K,1>& b)
  {
    return a<b[0];
  }
 
  template<class K>
  inline bool operator<= (const K a, const FieldVector<K,1>& b)
  {
    return a<=b[0];
  }
 
  template<class K>
  inline bool operator== (const K a, const FieldVector<K,1>& b)
  {
    return a==b[0];
  }
 
  template<class K>
  inline bool operator!= (const K a, const FieldVector<K,1>& b)
  {
    return a!=b[0];
  }
#endif
 
} // end namespace
 
#endif