AnalysisSystemForRadionucli.../include/armadillo_bits/constants.hpp
2024-06-04 15:25:02 +08:00

291 lines
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C++

// Copyright (C) 2008-2012 National ICT Australia (NICTA)
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.
// -------------------------------------------------------------------
//
// Written by Conrad Sanderson - http://conradsanderson.id.au
//! \addtogroup constants
//! @{
namespace priv
{
class Datum_helper
{
public:
template<typename eT>
static
typename arma_real_only<eT>::result
nan(typename arma_real_only<eT>::result* junk = 0)
{
arma_ignore(junk);
if(std::numeric_limits<eT>::has_quiet_NaN)
{
return std::numeric_limits<eT>::quiet_NaN();
}
else
{
return eT(0);
}
}
template<typename eT>
static
typename arma_cx_only<eT>::result
nan(typename arma_cx_only<eT>::result* junk = 0)
{
arma_ignore(junk);
typedef typename get_pod_type<eT>::result T;
return eT( Datum_helper::nan<T>(), Datum_helper::nan<T>() );
}
template<typename eT>
static
typename arma_integral_only<eT>::result
nan(typename arma_integral_only<eT>::result* junk = 0)
{
arma_ignore(junk);
return eT(0);
}
template<typename eT>
static
typename arma_real_only<eT>::result
inf(typename arma_real_only<eT>::result* junk = 0)
{
arma_ignore(junk);
if(std::numeric_limits<eT>::has_infinity)
{
return std::numeric_limits<eT>::infinity();
}
else
{
return std::numeric_limits<eT>::max();
}
}
template<typename eT>
static
typename arma_cx_only<eT>::result
inf(typename arma_cx_only<eT>::result* junk = 0)
{
arma_ignore(junk);
typedef typename get_pod_type<eT>::result T;
return eT( Datum_helper::inf<T>(), Datum_helper::inf<T>() );
}
template<typename eT>
static
typename arma_integral_only<eT>::result
inf(typename arma_integral_only<eT>::result* junk = 0)
{
arma_ignore(junk);
return std::numeric_limits<eT>::max();
}
};
}
//! various constants.
//! Physical constants taken from NIST 2010 CODATA values, and some from WolframAlpha (values provided as of 2009-06-23)
//! http://physics.nist.gov/cuu/Constants
//! http://www.wolframalpha.com
//! See also http://en.wikipedia.org/wiki/Physical_constant
template<typename eT>
class Datum
{
public:
static const eT pi; //!< ratio of any circle's circumference to its diameter
static const eT e; //!< base of the natural logarithm
static const eT euler; //!< Euler's constant, aka Euler-Mascheroni constant
static const eT gratio; //!< golden ratio
static const eT sqrt2; //!< square root of 2
static const eT eps; //!< the difference between 1 and the least value greater than 1 that is representable
static const eT log_min; //!< log of the minimum representable value
static const eT log_max; //!< log of the maximum representable value
static const eT nan; //!< "not a number"
static const eT inf; //!< infinity
//
static const eT m_u; //!< atomic mass constant (in kg)
static const eT N_A; //!< Avogadro constant
static const eT k; //!< Boltzmann constant (in joules per kelvin)
static const eT k_evk; //!< Boltzmann constant (in eV/K)
static const eT a_0; //!< Bohr radius (in meters)
static const eT mu_B; //!< Bohr magneton
static const eT Z_0; //!< characteristic impedance of vacuum (in ohms)
static const eT G_0; //!< conductance quantum (in siemens)
static const eT k_e; //!< Coulomb's constant (in meters per farad)
static const eT eps_0; //!< electric constant (in farads per meter)
static const eT m_e; //!< electron mass (in kg)
static const eT eV; //!< electron volt (in joules)
static const eT ec; //!< elementary charge (in coulombs)
static const eT F; //!< Faraday constant (in coulombs)
static const eT alpha; //!< fine-structure constant
static const eT alpha_inv; //!< inverse fine-structure constant
static const eT K_J; //!< Josephson constant
static const eT mu_0; //!< magnetic constant (in henries per meter)
static const eT phi_0; //!< magnetic flux quantum (in webers)
static const eT R; //!< molar gas constant (in joules per mole kelvin)
static const eT G; //!< Newtonian constant of gravitation (in newton square meters per kilogram squared)
static const eT h; //!< Planck constant (in joule seconds)
static const eT h_bar; //!< Planck constant over 2 pi, aka reduced Planck constant (in joule seconds)
static const eT m_p; //!< proton mass (in kg)
static const eT R_inf; //!< Rydberg constant (in reciprocal meters)
static const eT c_0; //!< speed of light in vacuum (in meters per second)
static const eT sigma; //!< Stefan-Boltzmann constant
static const eT R_k; //!< von Klitzing constant (in ohms)
static const eT b; //!< Wien wavelength displacement law constant
};
// the long lengths of the constants are for future support of "long double"
// and any smart compiler that does high-precision computation at compile-time
template<typename eT> const eT Datum<eT>::pi = eT(3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679);
template<typename eT> const eT Datum<eT>::e = eT(2.7182818284590452353602874713526624977572470936999595749669676277240766303535475945713821785251664274);
template<typename eT> const eT Datum<eT>::euler = eT(0.5772156649015328606065120900824024310421593359399235988057672348848677267776646709369470632917467495);
template<typename eT> const eT Datum<eT>::gratio = eT(1.6180339887498948482045868343656381177203091798057628621354486227052604628189024497072072041893911374);
template<typename eT> const eT Datum<eT>::sqrt2 = eT(1.4142135623730950488016887242096980785696718753769480731766797379907324784621070388503875343276415727);
template<typename eT> const eT Datum<eT>::eps = std::numeric_limits<eT>::epsilon();
template<typename eT> const eT Datum<eT>::log_min = std::log(std::numeric_limits<eT>::min());
template<typename eT> const eT Datum<eT>::log_max = std::log(std::numeric_limits<eT>::max());
template<typename eT> const eT Datum<eT>::nan = priv::Datum_helper::nan<eT>();
template<typename eT> const eT Datum<eT>::inf = priv::Datum_helper::inf<eT>();
template<typename eT> const eT Datum<eT>::m_u = eT(1.660539040e-27);
template<typename eT> const eT Datum<eT>::N_A = eT(6.022140857e23);
template<typename eT> const eT Datum<eT>::k = eT(1.38064852e-23);
template<typename eT> const eT Datum<eT>::k_evk = eT(8.6173303e-5);
template<typename eT> const eT Datum<eT>::a_0 = eT(0.52917721067e-10);
template<typename eT> const eT Datum<eT>::mu_B = eT(927.4009994e-26);
template<typename eT> const eT Datum<eT>::Z_0 = eT(376.730313461771);
template<typename eT> const eT Datum<eT>::G_0 = eT(7.7480917310e-5);
template<typename eT> const eT Datum<eT>::k_e = eT(8.9875517873681764e9);
template<typename eT> const eT Datum<eT>::eps_0 = eT(8.85418781762039e-12);
template<typename eT> const eT Datum<eT>::m_e = eT(9.10938356e-31);
template<typename eT> const eT Datum<eT>::eV = eT(1.6021766208e-19);
template<typename eT> const eT Datum<eT>::ec = eT(1.6021766208e-19);
template<typename eT> const eT Datum<eT>::F = eT(96485.33289);
template<typename eT> const eT Datum<eT>::alpha = eT(7.2973525664e-3);
template<typename eT> const eT Datum<eT>::alpha_inv = eT(137.035999139);
template<typename eT> const eT Datum<eT>::K_J = eT(483597.8525e9);
template<typename eT> const eT Datum<eT>::mu_0 = eT(1.25663706143592e-06);
template<typename eT> const eT Datum<eT>::phi_0 = eT(2.067833667e-15);
template<typename eT> const eT Datum<eT>::R = eT(8.3144598);
template<typename eT> const eT Datum<eT>::G = eT(6.67408e-11);
template<typename eT> const eT Datum<eT>::h = eT(6.626070040e-34);
template<typename eT> const eT Datum<eT>::h_bar = eT(1.054571800e-34);
template<typename eT> const eT Datum<eT>::m_p = eT(1.672621898e-27);
template<typename eT> const eT Datum<eT>::R_inf = eT(10973731.568508);
template<typename eT> const eT Datum<eT>::c_0 = eT(299792458.0);
template<typename eT> const eT Datum<eT>::sigma = eT(5.670367e-8);
template<typename eT> const eT Datum<eT>::R_k = eT(25812.8074555);
template<typename eT> const eT Datum<eT>::b = eT(2.8977729e-3);
typedef Datum<float> fdatum;
typedef Datum<double> datum;
namespace priv
{
template<typename eT>
static
arma_inline
arma_hot
typename arma_real_only<eT>::result
most_neg(typename arma_real_only<eT>::result* junk = 0)
{
arma_ignore(junk);
if(std::numeric_limits<eT>::has_infinity)
{
return -(std::numeric_limits<eT>::infinity());
}
else
{
return -(std::numeric_limits<eT>::max());
}
}
template<typename eT>
static
arma_inline
arma_hot
typename arma_integral_only<eT>::result
most_neg(typename arma_integral_only<eT>::result* junk = 0)
{
arma_ignore(junk);
return std::numeric_limits<eT>::min();
}
template<typename eT>
static
arma_inline
arma_hot
typename arma_real_only<eT>::result
most_pos(typename arma_real_only<eT>::result* junk = 0)
{
arma_ignore(junk);
if(std::numeric_limits<eT>::has_infinity)
{
return std::numeric_limits<eT>::infinity();
}
else
{
return std::numeric_limits<eT>::max();
}
}
template<typename eT>
static
arma_inline
arma_hot
typename arma_integral_only<eT>::result
most_pos(typename arma_integral_only<eT>::result* junk = 0)
{
arma_ignore(junk);
return std::numeric_limits<eT>::max();
}
}
//! @}