Teuchos_ScalarTraits.cpp

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#include "Teuchos_ScalarTraits.hpp"
#include "Teuchos_Assert.hpp"

// Define this to throw exceptions when any Teuchos::ScalarTraits function
// encounters a NaN or an Inf.
//#define TEUCHOS_SCALAR_TRAITS_THROW_NAN_INF_ERR


namespace {

// These functions exist to trick the compiler into not returning a warning
// message for 0.0/0.0 or refusing to compile the code.  If a compiler gets
// too smart, we can put these definitions into a different *.cpp file such
// that most compilers would not be able to know at compile-time if a NaN or
// an Inf was being created.

float returnFloatZero() { return 0.0; }

double returnDoubleZero() { return 0.0; }

} // namespace


void Teuchos::throwScalarTraitsNanInfError( const std::string &errMsg )
{
#ifdef TEUCHOS_SCALAR_TRAITS_THROW_NAN_INF_ERR
  TEUCHOS_TEST_FOR_EXCEPTION( true, std::runtime_error, errMsg );
#endif
}

#ifdef HAVE_TEUCHOS_GNU_MP
gmp_randclass Teuchos::gmp_rng ( gmp_randinit_default );
#endif

#ifdef HAVE_TEUCHOS_QD
bool Teuchos::operator&&(const dd_real &a, const dd_real &b) {
  return !a.is_zero() && !b.is_zero();
}
bool Teuchos::operator&&(const qd_real &a, const qd_real &b) {
  return !a.is_zero() && !b.is_zero();
}
#endif

#ifndef __sun
// This is an intentional computation of NaN.
namespace Teuchos {
const float  flt_nan = +returnFloatZero()/returnFloatZero();
const double dbl_nan = +returnDoubleZero()/returnDoubleZero();
}
#endif