std::mersenne_twister_engine<UIntType,w,n,m,r,a,u,d,s,b,t,c,l,f>::seed - cppreference.com (original) (raw)
void seed( result_type value = default_seed ); | (1) | (since C++11) |
---|---|---|
template< class SeedSeq > void seed( SeedSeq& seq ); | (2) | (since C++11) |
Sets the state of the random-number engine.
[edit] Parameters
value | - | seed value to use to set the state |
---|---|---|
seq | - | seed sequence to use to set the state |
[edit] Exceptions
- If
SeedSeq
is not std::seed_seq, throws the exceptions thrown by theseq.generate
call.
[edit] Complexity
Defect reports
The following behavior-changing defect reports were applied retroactively to previously published C++ standards.
DR | Applied to | Behavior as published | Correct behavior |
---|---|---|---|
LWG 2181 | C++11 | overload (2) would not throw even if the seq.generate call throws | propagates the exception |
[edit] See also
[edit] Example
#include #include int main() { std::mt19937 gen; // Seed the engine with an unsigned int gen.seed(1); std::cout << "after seed by 1: " << gen() << '\n'; // Seed the engine with two unsigned ints std::seed_seq sseq{1, 2}; gen.seed(sseq); std::cout << "after seed by {1,2}: " << gen() << '\n'; }
Possible output:
after seed by 1: 1791095845 after seed by {1,2}: 3127717181