https://svn.boost.org/trac10/ticket/5572 <p> Many accumulators tests are now failing on both trunk and release. I have tracked it down to recent changes in Boost.Random. I don't know for how long this has been happening. </p> <p> The accumulators tests use the lagged_fibonacci607 random number generator. The tests work by sending a large amount of random data through various statistical accumulators and checking that the results are within a certain tolerance of what they would be if the data were actually random. In Boost 1.45 and previous versions, this worked. (I haven't tested 1.46.) Trunk and release are hosed, leading me to suspect that this random number generator is no longer producing sufficiently random data. </p> <p> I have verified this by replacing boost/random on trunk with the one from 1.45. With this change, the accumulators tests pass. </p> <p> Steven, this seems like a regression. Can you look into this? </p> en-us /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/5572 Trac 1.4.3 Eric Niebler Fri, 27 May 2011 05:14:15 GMT https://svn.boost.org/trac10/ticket/5572#comment:1 https://svn.boost.org/trac10/ticket/5572#comment:1 <ul> <li><strong>owner</strong> changed from <span class="trac-author">No-Maintainer</span> to <span class="trac-author">Steven Watanabe</span> </li> </ul> Ticket Steven Watanabe Thu, 01 Dec 2011 18:36:39 GMT https://svn.boost.org/trac10/ticket/5572#comment:2 https://svn.boost.org/trac10/ticket/5572#comment:2 <ul> <li><strong>status</strong> <span class="trac-field-old">new</span> → <span class="trac-field-new">closed</span> </li> <li><strong>resolution</strong> → <span class="trac-field-new">fixed</span> </li> </ul> <p> The problem is not that the output is not sufficiently random, but that it changed. The Accumulators tests were tuned for the exact output that lagged_fibonacci607 used to produce. I adjusted the tests to so that they now pass again. </p> Ticket