//! More...
Functions | |
template<typename T1 > | |
arma_warn_unused T1::elem_type | trace (const Base< typename T1::elem_type, T1 > &X) |
Immediate trace (sum of diagonal elements) of a square dense matrix. | |
template<typename T1 > | |
arma_warn_unused T1::elem_type | trace (const Op< T1, op_diagmat > &X) |
template<typename T1 , typename T2 > | |
arma_warn_unused T1::elem_type | trace (const Glue< T1, T2, glue_times > &X) |
speedup for trace(A*B), where the result of A*B is a square sized matrix |
//!
arma_warn_unused T1::elem_type trace | ( | const Base< typename T1::elem_type, T1 > & | X | ) | [inline] |
Immediate trace (sum of diagonal elements) of a square dense matrix.
Definition at line 26 of file fn_trace.hpp.
References Base< elem_type, derived >::get_ref().
arma_warn_unused T1::elem_type trace | ( | const Op< T1, op_diagmat > & | X | ) | [inline] |
Definition at line 53 of file fn_trace.hpp.
References Op< T1, op_type >::m, and diagmat_proxy< T1 >::n_elem.
{ arma_extra_debug_sigprint(); typedef typename T1::elem_type eT; const diagmat_proxy<T1> A(X.m); const u32 N = A.n_elem; eT val = eT(0); for(u32 i=0; i<N; ++i) { val += A[i]; } return val; }
arma_warn_unused T1::elem_type trace | ( | const Glue< T1, T2, glue_times > & | X | ) | [inline] |
speedup for trace(A*B), where the result of A*B is a square sized matrix
Definition at line 79 of file fn_trace.hpp.
References Glue< T1, T2, glue_type >::A, Mat< eT >::at(), Glue< T1, T2, glue_type >::B, Mat< eT >::colptr(), unwrap< T1 >::M, Mat< eT >::n_cols, and Mat< eT >::n_rows.
{ arma_extra_debug_sigprint(); typedef typename T1::elem_type eT; const unwrap<T1> tmp1(X.A); const unwrap<T2> tmp2(X.B); const Mat<eT>& A = tmp1.M; const Mat<eT>& B = tmp2.M; arma_debug_assert_mul_size(A, B, "matrix multiply"); arma_debug_check( (A.n_rows != B.n_cols), "trace(): matrix must be square sized" ); const u32 N1 = A.n_rows; const u32 N2 = A.n_cols; eT val = eT(0); for(u32 i=0; i<N1; ++i) { const eT* B_colmem = B.colptr(i); eT acc = eT(0); for(u32 j=0; j<N2; ++j) { acc += A.at(i,j) * B_colmem[j]; } val += acc; } return val; }