// 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;
}
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 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;
}