Eigen::internal::std_fallback Namespace Reference

Functions
template<typename Scalar >
EIGEN_DEVICE_FUNC Scalar	expm1 (const Scalar &x)
template<typename Scalar >
EIGEN_DEVICE_FUNC Scalar	log1p (const Scalar &x)

Function Documentation

expm1()

template<typename Scalar >

EIGEN_DEVICE_FUNC Scalar Eigen::internal::std_fallback::expm1 ( const Scalar &  x )

inline

                                                       {
  EIGEN_STATIC_ASSERT_NON_INTEGER(Scalar)
  typedef typename NumTraits<Scalar>::Real RealScalar;
 
  EIGEN_USING_STD(exp);
  Scalar u = exp(x);
  if (numext::equal_strict(u, Scalar(1))) {
    return x;
  }
  Scalar um1 = u - RealScalar(1);
  if (numext::equal_strict(um1, Scalar(-1))) {
    return RealScalar(-1);
  }
 
  EIGEN_USING_STD(log);
  Scalar logu = log(u);
  return numext::equal_strict(u, logu) ? u : (u - RealScalar(1)) * x / logu;
}

References EIGEN_STATIC_ASSERT_NON_INTEGER, EIGEN_USING_STD, Eigen::numext::equal_strict(), Eigen::numext::exp(), Eigen::numext::log(), and plotDoE::x.

Referenced by Eigen::numext::EIGEN_MATHFUNC_RETVAL(), and Eigen::internal::expm1_impl< Scalar >::run().

log1p()

template<typename Scalar >

EIGEN_DEVICE_FUNC Scalar Eigen::internal::std_fallback::log1p ( const Scalar &  x )

inline

                                                       {
  EIGEN_STATIC_ASSERT_NON_INTEGER(Scalar)
  typedef typename NumTraits<Scalar>::Real RealScalar;
  EIGEN_USING_STD(log);
  Scalar x1p = RealScalar(1) + x;
  Scalar log_1p = log_impl<Scalar>::run(x1p);
  const bool is_small = numext::equal_strict(x1p, Scalar(1));
  const bool is_inf = numext::equal_strict(x1p, log_1p);
  return (is_small || is_inf) ? x : x * (log_1p / (x1p - RealScalar(1)));
}

References EIGEN_STATIC_ASSERT_NON_INTEGER, EIGEN_USING_STD, Eigen::numext::equal_strict(), Eigen::numext::log(), Eigen::internal::log_impl< Scalar >::run(), and plotDoE::x.

Referenced by Eigen::internal::log1p_impl< Scalar >::run(), and Eigen::internal::log1p_impl< std::complex< RealScalar > >::run().