ran.h

   1 #ifndef RAN_H
   2 #define RAN_H
   3
   4 #include "qp3.h"
   5
   6 struct Ran {
   7     Ullong u,v,w;
   8     Ran(Ullong j) : v(4101842887655102017LL), w(1) {
   9         // Constructor. Call with any integer seed (except value of v above).
  10         u = j ^ v; int64();
  11         v = u; int64();
  12         w = v; int64();
  13     }
  14     inline Ullong int64() {
  15         // Return 64-bit random integer.
  16         u = u * 2862933555777941757LL + 7046029254386353087LL;
  17         v ^= v >> 17; v ^= v << 31; v ^= v >> 8;
  18         w = 4294957665U*(w & 0xffffffff) + (w >> 32);
  19         Ullong x = u ^ (u << 21); x ^= x >> 35; x ^= x << 4;
  20         return (x + v) ^ w;
  21     }
  22     inline Doub doub() { return 5.42101086242752217E-20 * int64(); }
  23     // Return random double-precision floating value in the range 0. to 1.
  24     inline Uint int32() { return (Uint)int64(); }
  25     // Return 32-bit random integer.
  26 };
  27
  28 struct Ranq1 {
  29     Ullong v;
  30     Ranq1(Ullong j) : v(4101842887655102017LL) {
  31         v ^= j;
  32         v = int64();
  33     }
  34     inline Ullong int64() {
  35         v ^= v >> 21; v ^= v << 35; v ^= v >> 4;
  36         return v * 2685821657736338717LL;
  37     }
  38     inline Doub doub() { return 5.42101086242752217E-20 * int64(); }
  39     inline Uint int32() { return (Uint)int64(); }
  40 };
  41
  42 struct Ranq2 {
  43     Ullong v,w;
  44     Ranq2(Ullong j) : v(4101842887655102017LL), w(1) {
  45         v ^= j;
  46         w = int64();
  47         v = int64();
  48     }
  49     inline Ullong int64() {
  50         v ^= v >> 17; v ^= v << 31; v ^= v >> 8;
  51         w = 4294957665U*(w & 0xffffffff) + (w >> 32);
  52     return v ^ w;
  53     }
  54     inline Doub doub() { return 5.42101086242752217E-20 * int64(); }
  55     inline Uint int32() { return (Uint)int64(); }
  56 };
  57
  58 #endif // RAN_H