Hi all, I'm having some difficulty understanding my options for seeding the base generators in mersenne_twister.hpp. I'm interested in the array initialization that is somewhat obtusely mentioned in the documentation. In boost/random/mersenne_twister.hpp I see the following relevant items: template<class It> mersenne_twister(It& first, It last) { seed(first,last); } ... template<class It> void seed(It& first, It last) { int j; for(j = 0; j < n && first != last; ++j, ++first) x[j] = *first; i = n; if(first == last && j < n) throw std::invalid_argument("mersenne_twister::seed"); } I gather that "It" is some kind of iterator, and the natural candidate would be something like std::vector<uint32_t>::iterator, but not having truly come to terms with templates, it is unclear to me how to actually call this. The following minimal code snippet fails to compile with g++ (gcc version 3.3 20030304 (Apple Computer, Inc. build 1671)). Errors below. #include <iostream> #include <vector> #include <boost/random.hpp> typedef boost::mt19937 Mt19937BaseGenerator; // base generator typedef boost::uniform_real<> UniformReal; // distribution // variate generator typedef boost::variate_generator<Mt19937BaseGenerator&, UniformReal> Mt19937UniformRealGenerator; int main() { std::vector<uint32_t> seedVector(4); seedVector[0] = 12345u; // make up some seeds seedVector[1] = 98765u; seedVector[2] = 12942u; seedVector[3] = 20343u; // attempt to seed with vector iterators Mt19937BaseGenerator mt19937Generator(seedVector.begin(), seedVector.end()); UniformReal distribution(0, 1); Mt19937UniformRealGenerator myGen(mt19937Generator, distribution); for (unsigned i = 0; i < 100; ++i) { std::cout << myGen() << std::endl; } return 0; } mt19937Seed.cpp: In function `int main()': mt19937Seed.cpp:18: error: no matching function for call to ` boost::random::mersenne_twister<uint32_t, 32, 624, 397, 31, 0x09908b0df, 11, 7, 0x09d2c5680, 15, 0x0efc60000, 18, 0x0c77666de>::mersenne_twister( __gnu_cxx::__normal_iterator<uint32_t*, std::vector<uint32_t, std::allocator<uint32_t> > >, __gnu_cxx::__normal_iterator<uint32_t*, std::vector<uint32_t, std::allocator<uint32_t> > >)' /sw/include/boost/random/mersenne_twister.hpp:43: error: candidates are: boost::random::mersenne_twister<uint32_t, 32, 624, 397, 31, 0x09908b0df, 11, 7, 0x09d2c5680, 15, 0x0efc60000, 18, 0x0c77666de>::mersenne_twister(const boost::random::mersenne_twister<uint32_t, 32, 624, 397, 31, 0x09908b0df, 11, 7, 0x09d2c5680, 15, 0x0efc60000, 18, 0x0c77666de>&) /sw/include/boost/random/mersenne_twister.hpp:69: error: boost::random::mersenne_twister<UIntType, w, n, m, r, a, u, s, b, t, c, l, val>::mersenne_twister(It&, It) [with It = __gnu_cxx::__normal_iterator<uint32_t*, std::vector<uint32_t, std::allocator<uint32_t> > >, UIntType = uint32_t, int w = 32, int n = 624, int m = 397, int r = 31, UIntType a = 0x09908b0df, int u = 11, int s = 7, UIntType b = 0x09d2c5680, int t = 15, UIntType c = 0x0efc60000, int l = 18, UIntType val = 0x0c77666de] /sw/include/boost/random/mersenne_twister.hpp:68: error: boost::random::mersenne_twister<UIntType, w, n, m, r, a, u, s, b, t, c, l, val>::mersenne_twister(UIntType) [with UIntType = uint32_t, int w = 32, int n = 624, int m = 397, int r = 31, UIntType a = 0x09908b0df, int u = 11, int s = 7, UIntType b = 0x09d2c5680, int t = 15, UIntType c = 0x0efc60000, int l = 18, UIntType val = 0x0c77666de] /sw/include/boost/random/mersenne_twister.hpp:60: error: boost::random::mersenne_twister<UIntType, w, n, m, r, a, u, s, b, t, c, l, val>::mersenne_twister() [with UIntType = uint32_t, int w = 32, int n = 624, int m = 397, int r = 31, UIntType a = 0x09908b0df, int u = 11, int s = 7, UIntType b = 0x09d2c5680, int t = 15, UIntType c = 0x0efc60000, int l = 18, UIntType val = 0x0c77666de] Any help? I always have a really hard time interpreting template-related compiler errors. Thanks, Matt -- Matt Holland Population Biology Graduate Group University of California Davis, CA 95616