[Boost-bugs] [Boost C++ Libraries] #1829: norm_2 may return QNAN if BOOST_UBLAS_SCALED_NORM is defined

Subject: [Boost-bugs] [Boost C++ Libraries] #1829: norm_2 may return QNAN if BOOST_UBLAS_SCALED_NORM is defined
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2008-04-15 11:29:22

#1829: norm_2 may return QNAN if BOOST_UBLAS_SCALED_NORM is defined
--------------------------------+-------------------------------------------
 Reporter:  mortituris_at_[hidden]  |       Owner:  guwi17 
     Type:  Bugs                |      Status:  new    
Milestone:  Boost 1.36.0        |   Component:  uBLAS  
  Version:  Boost 1.35.0        |    Severity:  Problem
 Keywords:                      |  
--------------------------------+-------------------------------------------
 functional.hpp contains a bug which causes norm_2 to return QNAN if the
 first component of a vector is zero. The bug is in the
 `vector_norm_2::apply` method. It can be fixed by adding `if (0 == u)
 continue;` line before
 {{{
 if (scale < u) {
     real_type v (scale / u);
     sum_squares = sum_squares * v * v + real_type (1);
     scale = u;
 } else {
     real_type v (u / scale);
     sum_squares += v * v;
 }
 }}}

-- 
Ticket URL: <http://svn.boost.org/trac/boost/ticket/1829>
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