mirror of
https://github.com/ecency/ecency-mobile.git
synced 2024-12-22 12:51:42 +03:00
80 lines
2.6 KiB
C++
80 lines
2.6 KiB
C++
//Copyright (c) 2008-2016 Emil Dotchevski and Reverge Studios, Inc.
|
|
|
|
//Distributed under the Boost Software License, Version 1.0. (See accompanying
|
|
//file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
|
|
|
|
#ifndef UUID_3DCF6B90AE0E11DE9A315BE555D89593
|
|
#define UUID_3DCF6B90AE0E11DE9A315BE555D89593
|
|
|
|
#include <boost/qvm/inline.hpp>
|
|
#include <boost/qvm/mat_traits_array.hpp>
|
|
#include <boost/qvm/static_assert.hpp>
|
|
|
|
namespace
|
|
boost
|
|
{
|
|
namespace
|
|
qvm
|
|
{
|
|
namespace
|
|
qvm_detail
|
|
{
|
|
template <int N>
|
|
struct
|
|
det_size
|
|
{
|
|
};
|
|
|
|
template <class M>
|
|
BOOST_QVM_INLINE_TRIVIAL
|
|
typename mat_traits<M>::scalar_type
|
|
determinant_impl_( M const & a, det_size<2> )
|
|
{
|
|
return
|
|
mat_traits<M>::template read_element<0,0>(a) * mat_traits<M>::template read_element<1,1>(a) -
|
|
mat_traits<M>::template read_element<1,0>(a) * mat_traits<M>::template read_element<0,1>(a);
|
|
}
|
|
|
|
template <class M,int N>
|
|
BOOST_QVM_INLINE_RECURSION
|
|
typename mat_traits<M>::scalar_type
|
|
determinant_impl_( M const & a, det_size<N> )
|
|
{
|
|
typedef typename mat_traits<M>::scalar_type T;
|
|
T m[N-1][N-1];
|
|
T det=T(0);
|
|
for( int j1=0; j1!=N; ++j1 )
|
|
{
|
|
for( int i=1; i!=N; ++i )
|
|
{
|
|
int j2 = 0;
|
|
for( int j=0; j!=N; ++j )
|
|
{
|
|
if( j==j1 )
|
|
continue;
|
|
m[i-1][j2] = mat_traits<M>::read_element_idx(i,j,a);
|
|
++j2;
|
|
}
|
|
}
|
|
T d=determinant_impl_(m,det_size<N-1>());
|
|
if( j1&1 )
|
|
d=-d;
|
|
det += mat_traits<M>::read_element_idx(0,j1,a) * d;
|
|
}
|
|
return det;
|
|
}
|
|
|
|
template <class M>
|
|
BOOST_QVM_INLINE_TRIVIAL
|
|
typename mat_traits<M>::scalar_type
|
|
determinant_impl( M const & a )
|
|
{
|
|
BOOST_QVM_STATIC_ASSERT(mat_traits<M>::rows==mat_traits<M>::cols);
|
|
return determinant_impl_(a,det_size<mat_traits<M>::rows>());
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
#endif
|