ceph/src/boost/boost/qvm/detail/cofactor_impl.hpp

   1 //Copyright (c) 2008-2016 Emil Dotchevski and Reverge Studios, Inc.
   2
   3 //Distributed under the Boost Software License, Version 1.0. (See accompanying
   4 //file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   5
   6 #ifndef UUID_995547FAAE0E11DE8CF511E755D89593
   7 #define UUID_995547FAAE0E11DE8CF511E755D89593
   8
   9 #include <boost/qvm/detail/determinant_impl.hpp>
  10 #include <boost/qvm/mat_traits.hpp>
  11 #include <boost/qvm/static_assert.hpp>
  12
  13 namespace
  14 boost
  15     {
  16     namespace
  17     qvm
  18         {
  19         namespace
  20         qvm_detail
  21             {
  22             template <class A>
  23             BOOST_QVM_INLINE_OPERATIONS
  24             typename deduce_mat<A>::type
  25             cofactor_impl( A const & a )
  26                 {
  27                 BOOST_QVM_STATIC_ASSERT(mat_traits<A>::rows==mat_traits<A>::cols);
  28                 int const N=mat_traits<A>::rows;
  29                 typedef typename mat_traits<A>::scalar_type T;
  30                 T c[N-1][N-1];
  31                 typedef typename deduce_mat<A>::type R;
  32                 R b;
  33                 for( int j=0; j!=N; ++j )
  34                     {
  35                     for( int i=0; i!=N; ++i )
  36                         {
  37                         int i1=0;
  38                         for( int ii=0; ii!=N; ++ii )
  39                             {
  40                             if( ii==i )
  41                                 continue;
  42                             int j1=0;
  43                             for( int jj=0; jj!=N; ++jj )
  44                                 {
  45                                 if( jj==j )
  46                                     continue;
  47                                 c[i1][j1] = mat_traits<A>::read_element_idx(ii,jj,a);
  48                                 ++j1;
  49                                 }
  50                             ++i1;
  51                             }
  52                         T det = determinant_impl(c);
  53                         if( (i+j)&1 )
  54                             det=-det;
  55                         mat_traits<R>::write_element_idx(i,j,b) = det;
  56                         }
  57                     }
  58                 return b;
  59                 }
  60             }
  61         }
  62     }
  63
  64 #endif