1 //Copyright (C) 2013 Steve Taylor (steve98654@gmail.com), Davis E. King
2 //License: Boost Software License.  See LICENSE.txt for full license.
3 #ifndef DLIB_NUMERIC_CONSTANTs_H_
4 #define DLIB_NUMERIC_CONSTANTs_H_
5 
6 namespace dlib
7 {
8 
9     // pi -- Pi
10     const double pi = 3.1415926535897932385;
11 
12     // e  -- Euler's Constant
13     const double e = 2.7182818284590452354;
14 
15     // sqrt_2 -- The square root of 2
16     const double sqrt_2 = 1.4142135623730950488;
17 
18     // sqrt_3 -- The square root of 3
19     const double sqrt_3 = 1.7320508075688772935;
20 
21     // log10_2 -- The logarithm base 10 of two
22     const double log10_2 = 0.30102999566398119521;
23 
24     // light_spd -- The speed of light in vacuum in meters per second
25     const double light_spd = 2.99792458e8;
26 
27     // newton_G  -- Newton's gravitational constant (in metric units of m^3/(kg*s^2))
28     const double newton_G = 6.67384e-11;
29 
30     // planck_cst -- Planck's constant (in units of Joules * seconds)
31     const double planck_cst = 6.62606957e-34;
32 
33     // golden_ratio -- The Golden Ratio
34     const double golden_ratio = 1.6180339887498948482;
35 
36     // euler_gamma -- The Euler Mascheroni Constant
37     const double euler_gamma = 0.5772156649015328606065;
38 
39     // catalan -- Catalan's Constant
40     const double catalan = 0.91596559417721901505;
41 
42     // glaisher -- Glaisher Kinkelin constant
43     const double glaisher = 1.2824271291006226369;
44 
45     // khinchin -- Khinchin's constant
46     const double khinchin = 2.6854520010653064453;
47 
48     // apery -- Apery's constant
49     const double apery = 1.2020569031595942854;
50 }
51 
52 #endif //DLIB_NUMERIC_CONSTANTs_H_
53 
54