Functions | |
template<typename T1 > | |
arma_warn_unused u32 | rank (const Base< typename T1::elem_type, T1 > &X, typename T1::pod_type tol=0.0, const typename arma_blas_type_only< typename T1::elem_type >::result *junk=0) |
arma_warn_unused u32 rank | ( | const Base< typename T1::elem_type, T1 > & | X, | |
typename T1::pod_type | tol = 0.0 , |
|||
const typename arma_blas_type_only< typename T1::elem_type >::result * | junk = 0 | |||
) | [inline] |
Definition at line 28 of file fn_rank.hpp.
References arma_print(), eop_aux::direct_eps(), Base< elem_type, derived >::get_ref(), max(), Mat< eT >::memptr(), Mat< eT >::n_elem, and auxlib::svd().
00033 { 00034 arma_extra_debug_sigprint(); 00035 00036 typedef typename T1::elem_type eT; 00037 typedef typename T1::pod_type T; 00038 00039 const unwrap<T1> tmp(X.get_ref()); 00040 const Mat<eT>& A = tmp.M; 00041 00042 Col<T> s; 00043 const bool status = auxlib::svd(s, A); 00044 00045 if(status == true) 00046 { 00047 if(tol == T(0)) 00048 { 00049 tol = (std::max)(A.n_rows, A.n_cols) * eop_aux::direct_eps(max(s)); 00050 } 00051 00052 // count non zero valued elements in s 00053 00054 const T* s_mem = s.memptr(); 00055 const u32 n_elem = s.n_elem; 00056 u32 count = 0; 00057 00058 for(u32 i=0; i<n_elem; ++i) 00059 { 00060 if(s_mem[i] > tol) 00061 { 00062 ++count; 00063 } 00064 } 00065 00066 return count; 00067 } 00068 else 00069 { 00070 arma_print("rank(): singular value decomposition failed"); 00071 return u32(0); 00072 } 00073 00074 }