[boost] Re: Get/set state in Mersenne Twister

From: Neal D. Becker (ndbecker2_at_[hidden])
Date: 2004-09-01 15:06:37

Neal D. Becker wrote:

> In order to serialize, it would be helpful to add an interface to
> mersenne_twister to get/set the state.  I don't think there is any I/F to
> get the state.
> 

Possible patch:
Index: mersenne_twister.hpp
===================================================================
RCS file: /cvsroot/boost/boost/boost/random/mersenne_twister.hpp,v
retrieving revision 1.16
diff -c -r1.16 mersenne_twister.hpp
*** mersenne_twister.hpp        27 Jul 2004 03:43:32 -0000      1.16
--- mersenne_twister.hpp        1 Sep 2004 20:05:31 -0000
***************
*** 171,176 ****
--- 171,183 ----
    { return !(*this == rhs); }
  #endif
  
+   template<typename cont_t>
+   void getstate (cont_t& c) const {
+     if (c.size() < stat_size)
+       throw std::invalid_argument("mersenne_twister::getstate");
+     std::copy (&x[0], &x[state_size], c.begin());
+   }
+ 
  private:
    // returns x(i-n+index), where index is in 0..n-1
    UIntType compute(unsigned int index) const