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BasicRandom.cc
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2 // $Id: BasicRandom.cc 3433 2014-07-23 08:17:03Z salam $
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30 
31 // nlo includes
32 #include "fastjet/internal/BasicRandom.hh"
33 
34 
35 FASTJET_BEGIN_NAMESPACE // defined in fastjet/internal/base.hh
36 
37 
38 //
39 // random number generator
40 // uses method of L'Ecuyer, (via F.James, comp. phys. comm. 60(1990)329)
41 //
42 int __default_random_generator(int *__iseed)
43 {
44  int __k = __iseed[0]/53668;
45  __iseed[0] = (__iseed[0] - __k*53668)*40014 - __k*12211;
46  if(__iseed[0] < 0) __iseed[0] += 2147483563;
47 
48  __k = __iseed[1]/52774;
49  __iseed[1] = (__iseed[1] - __k*52774)*40692 - __k*3791;
50  if(__iseed[1] < 0) __iseed[1] += 2147483399;
51 
52  int __iz = __iseed[0] - __iseed[1];
53  if(__iz < 1) __iz += 2147483562;
54 
55  return __iz;
56 }
57 
58 // global defined random number generator
59 BasicRandom<int> _G_random_int;
60 BasicRandom<double> _G_random_double;
61 
62 
63 FASTJET_END_NAMESPACE
64