dlib C++ Library - numeric_constants.h

//Copyright (C) 2013 Steve Taylor (steve98654@gmail.com), Davis E. King
//License: Boost Software License. See LICENSE.txt for full license.
#ifndef DLIB_NUMERIC_CONSTANTs_H_
#define DLIB_NUMERIC_CONSTANTs_H_
namespace dlib 
{
 // pi -- Pi
 constexpr double pi = 3.1415926535897932384626433832795029L;
 // pi_2 -- Pi / 2
 constexpr double pi_2 = 1.5707963267948966192313216916397514L;
 
 // pi_3 -- Pi / 3
 constexpr double pi_3 = 1.0471975511965977461542144610931676L;
 // pi_4 -- Pi / 4
 constexpr double pi_4 = 0.7853981633974483096156608458198757L;
 // e -- Euler's Constant
 constexpr double e = 2.7182818284590452353602874713526625L;
 constexpr double euler = e;
 // sqrt_2 -- The square root of 2
 constexpr double sqrt_2 = 1.4142135623730950488016887242096981L;
 // sqrt_3 -- The square root of 3
 constexpr double sqrt_3 = 1.7320508075688772935274463415058723L;
 // log10_2 -- The logarithm base 10 of two
 constexpr double log10_2 = 0.30102999566398119521;
 // light_spd -- The speed of light in vacuum in meters per second
 constexpr double light_spd = 2.99792458e8;
 // newton_G -- Newton's gravitational constant (in metric units of m^3/(kg*s^2))
 constexpr double newton_G = 6.67384e-11;
 // planck_cst -- Planck's constant (in units of Joules * seconds) 
 constexpr double planck_cst = 6.62606957e-34;
 // golden_ratio -- The Golden Ratio
 constexpr double golden_ratio = 1.6180339887498948482;
 // euler_gamma -- The Euler Mascheroni Constant 
 constexpr double euler_gamma = 0.5772156649015328606065120900824024L;
 // catalan -- Catalan's Constant
 constexpr double catalan = 0.91596559417721901505;
 // glaisher -- Glaisher Kinkelin constant
 constexpr double glaisher = 1.2824271291006226369;
 // khinchin -- Khinchin's constant
 constexpr double khinchin = 2.6854520010653064453;
 // apery -- Apery's constant
 constexpr double apery = 1.2020569031595942854;
}
#endif //DLIB_NUMERIC_CONSTANTs_H_