stdlib_constants.fypp

#:include "common.fypp"
#:set KINDS = REAL_KINDS
#:set R_KINDS_TYPES = list(zip(REAL_KINDS, REAL_TYPES, REAL_SUFFIX))
#:set C_KINDS_TYPES = list(zip(CMPLX_KINDS, CMPLX_TYPES, CMPLX_SUFFIX))

module stdlib_constants
    !! Constants
    !! ([Specification](../page/specs/stdlib_constants.html))
    use stdlib_kinds, only: #{for k in KINDS[:-1]}#${k}$, #{endfor}#${KINDS[-1]}$
    use stdlib_codata, only: SPEED_OF_LIGHT_IN_VACUUM, &
                             VACUUM_ELECTRIC_PERMITTIVITY, &
                             VACUUM_MAG_PERMEABILITY, &
                             PLANCK_CONSTANT, &
                             NEWTONIAN_CONSTANT_OF_GRAVITATION, &
                             STANDARD_ACCELERATION_OF_GRAVITY, &
                             ELEMENTARY_CHARGE, &
                             MOLAR_GAS_CONSTANT, &
                             FINE_STRUCTURE_CONSTANT, &
                             AVOGADRO_CONSTANT, &
                             BOLTZMANN_CONSTANT, &
                             STEFAN_BOLTZMANN_CONSTANT, &
                             WIEN_WAVELENGTH_DISPLACEMENT_LAW_CONSTANT, &
                             RYDBERG_CONSTANT, &
                             ELECTRON_MASS, &
                             PROTON_MASS, &
                             NEUTRON_MASS, &
                             ATOMIC_MASS_CONSTANT
    private

    ! mathematical constants
    #:for k in KINDS
    real(${k}$), parameter, public :: PI_${k}$ = acos(-1.0_${k}$) !! PI
    #:endfor
    
    ! Physical constants
    real(dp), parameter, public :: c = SPEED_OF_LIGHT_IN_VACUUM%value !! Speed of light in vacuum
    real(dp), parameter, public :: speed_of_light = SPEED_OF_LIGHT_IN_VACUUM%value !! Speed of light in vacuum
    real(dp), parameter, public :: mu_0 = VACUUM_MAG_PERMEABILITY%value !! vacuum mag. permeability
    real(dp), parameter, public :: epsilon_0 = VACUUM_ELECTRIC_PERMITTIVITY%value !! vacuum mag. permeability
    real(dp), parameter, public :: h = PLANCK_CONSTANT%value !! Planck constant
    real(dp), parameter, public :: Planck = PLANCK_CONSTANT%value !! Planck constant
    real(dp), parameter, public :: hbar = PLANCK_CONSTANT%value / PI_dp !! Reduced Planck constant
    real(dp), parameter, public :: G = NEWTONIAN_CONSTANT_OF_GRAVITATION%value !! Newtonian constant of gravitation
    real(dp), parameter, public :: gravitation_constant = NEWTONIAN_CONSTANT_OF_GRAVITATION%value !! Newtonian constant of gravitation
    real(dp), parameter, public :: g2 = STANDARD_ACCELERATION_OF_GRAVITY%value !! Standard acceleration of gravity
    real(dp), parameter, public :: e = ELEMENTARY_CHARGE%value !! Elementary charge
    real(dp), parameter, public :: R = MOLAR_GAS_CONSTANT%value !! Molar gas constant
    real(dp), parameter, public :: gas_constant = MOLAR_GAS_CONSTANT%value !! Molar gas constant 
    real(dp), parameter, public :: alpha = FINE_STRUCTURE_CONSTANT%value !! Fine structure constant
    real(dp), parameter, public :: fine_structure = FINE_STRUCTURE_CONSTANT%value !! Fine structure constant
    real(dp), parameter, public :: N_A  = AVOGADRO_CONSTANT%value !! Avogadro constant
    real(dp), parameter, public :: Avogadro = AVOGADRO_CONSTANT%value !! Avogadro constant
    real(dp), parameter, public :: k = BOLTZMANN_CONSTANT%value !! Boltzmann constant
    real(dp), parameter, public :: Boltzmann = BOLTZMANN_CONSTANT%value !! Boltzmann constant
    real(dp), parameter, public :: sigma = STEFAN_BOLTZMANN_CONSTANT%value !! Stefan-Boltzmann constant
    real(dp), parameter, public :: Stefan_Boltzmann = STEFAN_BOLTZMANN_CONSTANT%value !! Stefan-Boltzmann constant
    real(dp), parameter, public :: Wien = WIEN_WAVELENGTH_DISPLACEMENT_LAW_CONSTANT%value !! Wien wavelength displacement law constant
    real(dp), parameter, public :: Rydberg = RYDBERG_CONSTANT%value !! Rydberg constant
    real(dp), parameter, public :: m_e = ELECTRON_MASS%value !! Electron mass
    real(dp), parameter, public :: m_p = PROTON_MASS%value !! Proton mass
    real(dp), parameter, public :: m_n = NEUTRON_MASS%value !! Neutron mass
    real(dp), parameter, public :: m_u = ATOMIC_MASS_CONSTANT%value !! Atomic mass constant
    real(dp), parameter, public :: u = ATOMIC_MASS_CONSTANT%value !! Atomic mass constant

    ! Additional constants if needed
    #:for k, t, s in R_KINDS_TYPES
    ${t}$, parameter, public :: zero_${s}$ = 0._${k}$
    ${t}$, parameter, public :: one_${s}$  = 1._${k}$
    #:endfor
    #:for k, t, s in C_KINDS_TYPES
    ${t}$, parameter, public :: zero_${s}$ = (0._${k}$,0._${k}$)
    ${t}$, parameter, public :: one_${s}$  = (1._${k}$,0._${k}$)
    #:endfor

end module stdlib_constants