Boost C++ Libraries: Ticket #10179: wrong check on the Log Normal position parameter https://svn.boost.org/trac10/ticket/10179 <p> In the Log normal there is a chaco that does not allow to use negative numbers for mu (in the manual reference page it is know as position) For the moment I would refer to it as mu. Mu is the mean value of the log(x) and should be therefore between ]-inf,inf] since the log is defined between ]0,inf]. The problem highlights when we are seeking to represent a random variable which logarithm is normal distributed with mean negative. BTW even in the web page of the manual there are example with mu negative: <a href="http://www.boost.org/doc/libs/1_35_0/libs/math/doc/sf_and_dist/html/math_toolkit/dist/dist_ref/dists/lognormal_dist.html">http://www.boost.org/doc/libs/1_35_0/libs/math/doc/sf_and_dist/html/math_toolkit/dist/dist_ref/dists/lognormal_dist.html</a> </p> en-us Boost C++ Libraries /htdocs/site/boost.png https://svn.boost.org/trac10/ticket/10179 Trac 1.4.3 John Maddock Sat, 12 Jul 2014 18:07:43 GMT <link>https://svn.boost.org/trac10/ticket/10179#comment:1 </link> <guid isPermaLink="false">https://svn.boost.org/trac10/ticket/10179#comment:1</guid> <description> <p> Using either Boost-1.54 or latest Git develop the following works OK for me: </p> <pre class="wiki"> boost::math::lognormal d(-2.0, 1.0); std::cout &lt;&lt; pdf(d, 0.5) &lt;&lt; std::endl; std::cout &lt;&lt; cdf(d, 0.5) &lt;&lt; std::endl; std::cout &lt;&lt; quantile(d, 0.5) &lt;&lt; std::endl; </pre><p> What am I missing? </p> </description> <category>Ticket</category> </item> <item> <dc:creator>John Maddock</dc:creator> <pubDate>Mon, 05 Jan 2015 18:38:42 GMT</pubDate> <title/> <link>https://svn.boost.org/trac10/ticket/10179#comment:2 </link> <guid isPermaLink="false">https://svn.boost.org/trac10/ticket/10179#comment:2</guid> <description> <p> Ping??? </p> </description> <category>Ticket</category> </item> <item> <dc:creator>John Maddock</dc:creator> <pubDate>Thu, 05 Feb 2015 19:05:07 GMT</pubDate> <title>status changed; resolution set https://svn.boost.org/trac10/ticket/10179#comment:3 https://svn.boost.org/trac10/ticket/10179#comment:3 <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">invalid</span> </li> </ul> <p> No response so closing down, please reopen if you have a test case. </p> Ticket