Hello list, today I found out that boost::random, at least the combination boost::mt19937 rng(<seed>); typedef boost::uniform_int<int> dist_t; dist_t dist (<min>, <max>); boost::variate_generator< boost::mt19937&, dist_t
rand_ (rng, dist);
will give me different results depending on whether I use "g++ (Debian
4.3.2-1.1) 4.3.2" (with sizeof(long)=8) or "g++.exe (TDM-2 mingw32)
4.4.1" (with sizeof(long)=4).
This testcase:
++
#include
rand_ (rng, dist);
int main () { for (int i=0; i<6; ++i) { std::cout << rand_() << std::endl; } } -- will print 16 8 1 6 0 12 with the 64bit variant variant, but 7 16 12 15 0 2 with the 32bit variant. Is there a (preferably portable) way to ensure that they will be the same on all 32bit+ machines? Otherwise this would be a real stopper to use boost::random for me, and I'd have to go back to libcoyotl's Mersenne Twister, which gives consistent results, upon which I really depend. Sincerely Sebastian Mach phresnel@gmail.com