libtrilinos-dev 10.4.0.dfsg-1ubuntu2 / usr / include / trilinos / Sacado_Fad_ScalarTraitsImp.hpp

// $Id$ 
// $Source$ 
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// 
//                           Sacado Package
//                 Copyright (2006) Sandia Corporation
// 
// Under the terms of Contract DE-AC04-94AL85000 with Sandia Corporation,
// the U.S. Government retains certain rights in this software.
// 
// This library is free software; you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
// Lesser General Public License for more details.
//  
// You should have received a copy of the GNU Lesser General Public
// License along with this library; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
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// Questions? Contact David M. Gay (dmgay@sandia.gov) or Eric T. Phipps
// (etphipp@sandia.gov).
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#ifndef SACADO_FAD_SCALARTRAITSIMP_HPP
#define SACADO_FAD_SCALARTRAITSIMP_HPP

#ifdef HAVE_SACADO_TEUCHOS

#include "Teuchos_ScalarTraits.hpp"
#include "Teuchos_TestForException.hpp"
#include "Sacado_mpl_apply.hpp"

namespace Sacado {

  namespace Fad {

    //! Implementation for Teuchos::ScalarTraits for all Fad types
    template <typename FadType>
    struct ScalarTraitsImp {
      typedef typename Sacado::ValueType<FadType>::type ValueT;

      typedef typename mpl::apply<FadType,typename Teuchos::ScalarTraits<ValueT>::magnitudeType>::type magnitudeType;
      typedef typename mpl::apply<FadType,typename Teuchos::ScalarTraits<ValueT>::halfPrecision>::type halfPrecision;
      typedef typename mpl::apply<FadType,typename Teuchos::ScalarTraits<ValueT>::doublePrecision>::type doublePrecision;

      static const bool isComplex = Teuchos::ScalarTraits<ValueT>::isComplex;
      static const bool isOrdinal = Teuchos::ScalarTraits<ValueT>::isOrdinal;
      static const bool isComparable = 
	Teuchos::ScalarTraits<ValueT>::isComparable;
      static const bool hasMachineParameters = 
	Teuchos::ScalarTraits<ValueT>::hasMachineParameters;
      static typename Teuchos::ScalarTraits<ValueT>::magnitudeType eps() {
	return Teuchos::ScalarTraits<ValueT>::eps();
      }
      static typename Teuchos::ScalarTraits<ValueT>::magnitudeType sfmin() {
	return Teuchos::ScalarTraits<ValueT>::sfmin();
      }
      static typename Teuchos::ScalarTraits<ValueT>::magnitudeType base()  {
	return Teuchos::ScalarTraits<ValueT>::base();
      }
      static typename Teuchos::ScalarTraits<ValueT>::magnitudeType prec()  {
	return Teuchos::ScalarTraits<ValueT>::prec();
      }
      static typename Teuchos::ScalarTraits<ValueT>::magnitudeType t()     {
	return Teuchos::ScalarTraits<ValueT>::t();
      }
      static typename Teuchos::ScalarTraits<ValueT>::magnitudeType rnd()   {
	return Teuchos::ScalarTraits<ValueT>::rnd();
      }
      static typename Teuchos::ScalarTraits<ValueT>::magnitudeType emin()  {
	return Teuchos::ScalarTraits<ValueT>::emin();
      }
      static typename Teuchos::ScalarTraits<ValueT>::magnitudeType rmin()  {
	return Teuchos::ScalarTraits<ValueT>::rmin();
      }
      static typename Teuchos::ScalarTraits<ValueT>::magnitudeType emax()  {
	return Teuchos::ScalarTraits<ValueT>::emax();
      }
      static typename Teuchos::ScalarTraits<ValueT>::magnitudeType rmax()  {
	return Teuchos::ScalarTraits<ValueT>::rmax();
      }
      static magnitudeType magnitude(const FadType& a) {
#ifdef TEUCHOS_DEBUG
	TEUCHOS_SCALAR_TRAITS_NAN_INF_ERR(
	  a, "Error, the input value to magnitude(...) a = " << a << 
	  " can not be NaN!" );
	TEST_FOR_EXCEPTION(is_fad_real(a) == false, std::runtime_error,
			   "Complex magnitude is not a differentiable "
			   "function of complex inputs.");
#endif
	//return std::fabs(a); 
	magnitudeType b(a.size(), 
			Teuchos::ScalarTraits<ValueT>::magnitude(a.val()));
	if (Teuchos::ScalarTraits<ValueT>::real(a.val()) >= 0)
	  for (int i=0; i<a.size(); i++)
	    b.fastAccessDx(i) = 
	      Teuchos::ScalarTraits<ValueT>::magnitude(a.fastAccessDx(i));
	else
	  for (int i=0; i<a.size(); i++)
	    b.fastAccessDx(i) = 
	      -Teuchos::ScalarTraits<ValueT>::magnitude(a.fastAccessDx(i));
	return b;
      }
      static ValueT zero()  { 
	return ValueT(0.0); 
      }
      static ValueT one()   { 
	return ValueT(1.0); 
      }
      
      // Conjugate is only defined for real derivative components
      static FadType conjugate(const FadType& x) {
#ifdef TEUCHOS_DEBUG
	TEST_FOR_EXCEPTION(is_fad_real(x) == false, std::runtime_error,
			   "Complex conjugate is not a differentiable "
			   "function of complex inputs.");
#endif
	FadType y = x;
	y.val() = Teuchos::ScalarTraits<ValueT>::conjugate(x.val());
	return y;
      }   

      // Real part is only defined for real derivative components
      static FadType real(const FadType& x) { 
#ifdef TEUCHOS_DEBUG
	TEST_FOR_EXCEPTION(is_fad_real(x) == false, std::runtime_error,
			   "Real component is not a differentiable "
			   "function of complex inputs.");
#endif
	FadType y = x;
	y.val() = Teuchos::ScalarTraits<ValueT>::real(x.val());
	return y;
      }

      // Imaginary part is only defined for real derivative components
      static FadType imag(const FadType& x) { 
#ifdef TEUCHOS_DEBUG
	TEST_FOR_EXCEPTION(is_fad_real(x) == false, std::runtime_error,
			   "Imaginary component is not a differentiable "
			   "function of complex inputs.");
#endif
	return FadType(Teuchos::ScalarTraits<ValueT>::imag(x.val()));
      }

      static ValueT nan() {
	return Teuchos::ScalarTraits<ValueT>::nan(); 
      }
      static bool isnaninf(const FadType& x) { 
	if (Teuchos::ScalarTraits<ValueT>::isnaninf(x.val()))
	  return true;
	for (int i=0; i<x.size(); i++)
	  if (Teuchos::ScalarTraits<ValueT>::isnaninf(x.dx(i)))
	    return true;
	return false;
      }
      static void seedrandom(unsigned int s) { 
	Teuchos::ScalarTraits<ValueT>::seedrandom(s); 
      }
      static ValueT random() { 
	return Teuchos::ScalarTraits<ValueT>::random(); 
      }
      static std::string name() { 
	return Sacado::StringName<FadType>::eval(); 
      }
      static FadType squareroot(const FadType& x) {
#ifdef TEUCHOS_DEBUG
	TEUCHOS_SCALAR_TRAITS_NAN_INF_ERR(
	  x, "Error, the input value to squareroot(...) a = " << x << 
	  " can not be NaN!" );
#endif
	return std::sqrt(x); 
      }
      static FadType pow(const FadType& x, const FadType& y) { 
	return std::pow(x,y); 
      }

      // Helper function to determine whether a complex value is real
      static bool is_complex_real(const ValueT& x) {
	return 
	  Teuchos::ScalarTraits<ValueT>::magnitude(x-Teuchos::ScalarTraits<ValueT>::real(x)) == 0;
      }

      // Helper function to determine whether a Fad type is real
      static bool is_fad_real(const FadType& x) {
	if (x.size() == 0)
	  return true;
	if (Teuchos::ScalarTraits<ValueT>::isComplex) {
	  if (!is_complex_real(x.val()))
	    return false;
	  for (int i=0; i<x.size(); i++)
	    if (!is_complex_real(x.fastAccessDx(i)))
	      return false;
	}
	return true;
      }

    }; // class ScalarTraitsImp

  } // namespace Fad

} // namespace Sacado

#endif // HAVE_SACADO_TEUCHOS

#endif // SACADO_FAD_SCALARTRAITSIMP_HPP