[Boost-bugs] [Boost C++ Libraries] #11294: Matrix Memory problem after using lu_factorize

Subject: [Boost-bugs] [Boost C++ Libraries] #11294: Matrix Memory problem after using lu_factorize
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2015-05-13 08:17:17

#11294: Matrix Memory problem after using lu_factorize
------------------------------+---------------------
 Reporter:  michael.cortis@…  |      Owner:  guwi17
     Type:  Bugs              |     Status:  new
Milestone:  To Be Determined  |  Component:  uBLAS
  Version:  Boost 1.55.0      |   Severity:  Problem
 Keywords:                    |
------------------------------+---------------------
 Discovered that after using lu_factorize the values of the matrix have
 changed!


 {{{
 #include <iostream>

 #include <boost/date_time/posix_time/posix_time.hpp>
 #include <boost/numeric/ublas/matrix.hpp>
 #include <boost/numeric/ublas/matrix_proxy.hpp>
 #include <boost/numeric/ublas/vector.hpp>
 #include <boost/numeric/ublas/io.hpp>
 #include <boost/numeric/ublas/lu.hpp>

 using namespace std;
 using namespace boost::numeric;

 int main()
 {
   ublas::matrix<double> X(3,3); X.clear();
   X(0,0) = 0.995182407377577; X(0,1) =-0.006473367705848; X(0,2)
 =-0.002032391957706;
   X(1,0) =-0.006473367705848; X(1,1) = 0.995182407377577; X(1,2)
 =-0.002032391957706;
   X(2,0) =-0.002032391957706; X(2,1) =-0.002032391957706; X(2,2) =
 0.936175146339137;
   cout<<setprecision(16)<<X<<endl;
   cout<<ublas::lu_factorize(X)<<endl;
   cout<<setprecision(16)<<X<<endl;
   cout<<ublas::lu_factorize(X)<<endl;
   cout<<setprecision(16)<<X<<endl;
 }
 }}}

 Output:


 {{{
 [3,3]((0.995182407377577,-0.006473367705848,-0.002032391957706),(-0.006473367705848,0.995182407377577,-0.002032391957706),(-0.002032391957706,-0.002032391957706,0.936175146339137))
 0
 [3,3]((0.995182407377577,-0.006473367705848,-0.002032391957706),(-0.006504704723334175,0.9951403000320849,-0.002045612067272957),(-0.002042230592742885,-0.002055601674665375,0.9361667907625133))
 0
 [3,3]((0.995182407377577,-0.006473367705848,-0.002032391957706),(-0.006536193440632496,0.9950979888485471,-0.002058896174255709),(-0.002052116855767581,-0.002079077442455779,0.9361583394521271))

 }}}

 Is this fixed in newer versions?

 Thanks

 Michael Cortis

 RA, Durham University

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/11294>
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