Boost C++ Libraries: Ticket #599: uniform_01 copies engine instead of using a reference

status changed

jmaurer — Thu, 26 Apr 2007 20:16:49 GMT

status assigned → closed

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With the introduction of variate_generator<>, the random number engines have been redesigned some years ago. Unfortunately, boost/random/variate_generator.hpp now relies on uniform_01<> to take a value (as opposed to a reference).  Since I don't have time to fix the infrastructure properly, I've adjusted the documentation for uniform_01 in the CVS to reality, with a big warning hint.
If you want to have a  [0,1) generator, use uniform_real with appropriate parameters instead.

status changed; resolution deleted

azzie@… — Fri, 16 Nov 2007 20:43:04 GMT

status closed → reopened
resolution Fixed

I still haven't found this warning in http://www.boost.org/libs/random/random-distributions.html#uniform_01 and encountered the same problem. Please make clear that drawing a number from uniform_01 will NOT change the state of the passed generator. And why to pass the generator as a non-const reference if it is not being changed?

I suggest making the constructor argument (the reference to the generator) of uniform_01 const and pointing the users to uniform_real which works as expected (changes the state of the generator after drawing a number).

status changed; resolution set

Steven Watanabe — Thu, 19 Feb 2009 23:27:42 GMT

status reopened → closed
resolution → fixed

(In [51337]) Convert uniform_01 to the current distribution interface, dispatching on the first template paramter to retain backwards compatibility. Fixes #599. Fixes #1544. Fixes #2679