max@0: // Copyright (C) 2010-2011 NICTA (www.nicta.com.au)
max@0: // Copyright (C) 2010-2011 Conrad Sanderson
max@0: // 
max@0: // This file is part of the Armadillo C++ library.
max@0: // It is provided without any warranty of fitness
max@0: // for any purpose. You can redistribute this file
max@0: // and/or modify it under the terms of the GNU
max@0: // Lesser General Public License (LGPL) as published
max@0: // by the Free Software Foundation, either version 3
max@0: // of the License or (at your option) any later version.
max@0: // (see http://www.opensource.org/licenses for more info)
max@0: 
max@0: 
max@0: //! \addtogroup fn_as_scalar
max@0: //! @{
max@0: 
max@0: 
max@0: 
max@0: template<uword N>
max@0: struct as_scalar_redirect
max@0:   {
max@0:   template<typename T1>
max@0:   inline static typename T1::elem_type apply(const T1& X);
max@0:   };
max@0: 
max@0: 
max@0: 
max@0: template<>
max@0: struct as_scalar_redirect<2>
max@0:   {
max@0:   template<typename T1, typename T2>
max@0:   inline static typename T1::elem_type apply(const Glue<T1,T2,glue_times>& X);
max@0:   };
max@0: 
max@0: 
max@0: template<>
max@0: struct as_scalar_redirect<3>
max@0:   {
max@0:   template<typename T1, typename T2, typename T3>
max@0:   inline static typename T1::elem_type apply(const Glue< Glue<T1, T2, glue_times>, T3, glue_times>& X);
max@0:   };
max@0: 
max@0: 
max@0: 
max@0: template<uword N>
max@0: template<typename T1>
max@0: inline
max@0: typename T1::elem_type
max@0: as_scalar_redirect<N>::apply(const T1& X)
max@0:   {
max@0:   arma_extra_debug_sigprint();
max@0:   
max@0:   typedef typename T1::elem_type eT;
max@0:   
max@0:   const unwrap<T1>   tmp(X);
max@0:   const Mat<eT>& A = tmp.M;
max@0:   
max@0:   arma_debug_check( (A.n_elem != 1), "as_scalar(): expression doesn't evaluate to exactly one element" );
max@0:   
max@0:   return A.mem[0];
max@0:   }
max@0: 
max@0: 
max@0: 
max@0: template<typename T1, typename T2>
max@0: inline
max@0: typename T1::elem_type
max@0: as_scalar_redirect<2>::apply(const Glue<T1, T2, glue_times>& X)
max@0:   {
max@0:   arma_extra_debug_sigprint();
max@0:   
max@0:   typedef typename T1::elem_type eT;
max@0:   
max@0:   // T1 must result in a matrix with one row
max@0:   // T2 must result in a matrix with one column
max@0:   
max@0:   const partial_unwrap<T1> tmp1(X.A);
max@0:   const partial_unwrap<T2> tmp2(X.B);
max@0:   
max@0:   const Mat<eT>& A = tmp1.M;
max@0:   const Mat<eT>& B = tmp2.M;
max@0:   
max@0:   const uword A_n_rows = (tmp1.do_trans == false) ? A.n_rows : A.n_cols;
max@0:   const uword A_n_cols = (tmp1.do_trans == false) ? A.n_cols : A.n_rows;
max@0:   
max@0:   const uword B_n_rows = (tmp2.do_trans == false) ? B.n_rows : B.n_cols;
max@0:   const uword B_n_cols = (tmp2.do_trans == false) ? B.n_cols : B.n_rows;
max@0:   
max@0:   const eT val = tmp1.get_val() * tmp2.get_val();
max@0:   
max@0:   arma_debug_check( (A_n_rows != 1) || (B_n_cols != 1) || (A_n_cols != B_n_rows), "as_scalar(): incompatible dimensions" );
max@0:   
max@0:   return val * op_dot::direct_dot(A.n_elem, A.mem, B.mem);
max@0:   }
max@0: 
max@0: 
max@0: 
max@0: template<typename T1, typename T2, typename T3>
max@0: inline
max@0: typename T1::elem_type
max@0: as_scalar_redirect<3>::apply(const Glue< Glue<T1, T2, glue_times>, T3, glue_times >& X)
max@0:   {
max@0:   arma_extra_debug_sigprint();
max@0:   
max@0:   typedef typename T1::elem_type eT;
max@0:   
max@0:   // T1 * T2 must result in a matrix with one row
max@0:   // T3 must result in a matrix with one column
max@0:   
max@0:   typedef typename strip_inv    <T2           >::stored_type T2_stripped_1;
max@0:   typedef typename strip_diagmat<T2_stripped_1>::stored_type T2_stripped_2;
max@0:   
max@0:   const strip_inv    <T2>            strip1(X.A.B);
max@0:   const strip_diagmat<T2_stripped_1> strip2(strip1.M);
max@0:   
max@0:   const bool tmp2_do_inv     = strip1.do_inv;
max@0:   const bool tmp2_do_diagmat = strip2.do_diagmat;
max@0:   
max@0:   if(tmp2_do_diagmat == false)
max@0:     {
max@0:     const Mat<eT> tmp(X);
max@0:     
max@0:     arma_debug_check( (tmp.n_elem != 1), "as_scalar(): expression doesn't evaluate to exactly one element" );
max@0:     
max@0:     return tmp[0];
max@0:     }
max@0:   else
max@0:     {
max@0:     const partial_unwrap<T1>            tmp1(X.A.A);
max@0:     const partial_unwrap<T2_stripped_2> tmp2(strip2.M);
max@0:     const partial_unwrap<T3>            tmp3(X.B);
max@0:     
max@0:     const Mat<eT>& A = tmp1.M;
max@0:     const Mat<eT>& B = tmp2.M;
max@0:     const Mat<eT>& C = tmp3.M;
max@0:     
max@0:     const uword A_n_rows = (tmp1.do_trans == false) ? A.n_rows : A.n_cols;
max@0:     const uword A_n_cols = (tmp1.do_trans == false) ? A.n_cols : A.n_rows;
max@0:     
max@0:     const bool B_is_vec = B.is_vec();
max@0:     
max@0:     const uword B_n_rows = (B_is_vec == true) ? B.n_elem : ( (tmp2.do_trans == false) ? B.n_rows : B.n_cols );
max@0:     const uword B_n_cols = (B_is_vec == true) ? B.n_elem : ( (tmp2.do_trans == false) ? B.n_cols : B.n_rows );
max@0:     
max@0:     const uword C_n_rows = (tmp3.do_trans == false) ? C.n_rows : C.n_cols;
max@0:     const uword C_n_cols = (tmp3.do_trans == false) ? C.n_cols : C.n_rows;
max@0:     
max@0:     const eT val = tmp1.get_val() * tmp2.get_val() * tmp3.get_val();
max@0:     
max@0:     arma_debug_check
max@0:       (
max@0:       (A_n_rows != 1)        ||
max@0:       (C_n_cols != 1)        ||
max@0:       (A_n_cols != B_n_rows) ||
max@0:       (B_n_cols != C_n_rows)
max@0:       ,
max@0:       "as_scalar(): incompatible dimensions"
max@0:       );
max@0:     
max@0:     
max@0:     if(B_is_vec == true)
max@0:       {
max@0:       if(tmp2_do_inv == true)
max@0:         {
max@0:         return val * op_dotext::direct_rowvec_invdiagvec_colvec(A.mem, B, C.mem);
max@0:         }
max@0:       else
max@0:         {
max@0:         return val * op_dot::direct_dot(A.n_elem, A.mem, B.mem, C.mem);
max@0:         }
max@0:       }
max@0:     else
max@0:       {
max@0:       if(tmp2_do_inv == true)
max@0:         {
max@0:         return val * op_dotext::direct_rowvec_invdiagmat_colvec(A.mem, B, C.mem);
max@0:         }
max@0:       else
max@0:         {
max@0:         return val * op_dotext::direct_rowvec_diagmat_colvec(A.mem, B, C.mem);
max@0:         }
max@0:       }
max@0:     }
max@0:   }
max@0: 
max@0: 
max@0: 
max@0: template<typename T1>
max@0: inline
max@0: typename T1::elem_type
max@0: as_scalar_diag(const Base<typename T1::elem_type,T1>& X)
max@0:   {
max@0:   arma_extra_debug_sigprint();
max@0:   
max@0:   typedef typename T1::elem_type eT;
max@0:   
max@0:   const unwrap<T1>   tmp(X.get_ref());
max@0:   const Mat<eT>& A = tmp.M;
max@0:   
max@0:   arma_debug_check( (A.n_elem != 1), "as_scalar(): expression doesn't evaluate to exactly one element" );
max@0:   
max@0:   return A.mem[0];
max@0:   }
max@0: 
max@0: 
max@0: 
max@0: template<typename T1, typename T2, typename T3>
max@0: inline
max@0: typename T1::elem_type
max@0: as_scalar_diag(const Glue< Glue<T1, T2, glue_times_diag>, T3, glue_times >& X)
max@0:   {
max@0:   arma_extra_debug_sigprint();
max@0:   
max@0:   typedef typename T1::elem_type eT;
max@0:   
max@0:   // T1 * T2 must result in a matrix with one row
max@0:   // T3 must result in a matrix with one column
max@0:   
max@0:   typedef typename strip_diagmat<T2>::stored_type T2_stripped;
max@0:   
max@0:   const strip_diagmat<T2> strip(X.A.B);
max@0:   
max@0:   const partial_unwrap<T1>          tmp1(X.A.A);
max@0:   const partial_unwrap<T2_stripped> tmp2(strip.M);
max@0:   const partial_unwrap<T3>          tmp3(X.B);
max@0:   
max@0:   const Mat<eT>& A = tmp1.M;
max@0:   const Mat<eT>& B = tmp2.M;
max@0:   const Mat<eT>& C = tmp3.M;
max@0:   
max@0:   
max@0:   const uword A_n_rows = (tmp1.do_trans == false) ? A.n_rows : A.n_cols;
max@0:   const uword A_n_cols = (tmp1.do_trans == false) ? A.n_cols : A.n_rows;
max@0:   
max@0:   const bool B_is_vec = B.is_vec();
max@0:   
max@0:   const uword B_n_rows = (B_is_vec == true) ? B.n_elem : ( (tmp2.do_trans == false) ? B.n_rows : B.n_cols );
max@0:   const uword B_n_cols = (B_is_vec == true) ? B.n_elem : ( (tmp2.do_trans == false) ? B.n_cols : B.n_rows );
max@0:   
max@0:   const uword C_n_rows = (tmp3.do_trans == false) ? C.n_rows : C.n_cols;
max@0:   const uword C_n_cols = (tmp3.do_trans == false) ? C.n_cols : C.n_rows;
max@0:   
max@0:   const eT val = tmp1.get_val() * tmp2.get_val() * tmp3.get_val();
max@0:   
max@0:   arma_debug_check
max@0:     (
max@0:     (A_n_rows != 1)        ||
max@0:     (C_n_cols != 1)        ||
max@0:     (A_n_cols != B_n_rows) ||
max@0:     (B_n_cols != C_n_rows)
max@0:     ,
max@0:     "as_scalar(): incompatible dimensions"
max@0:     );
max@0:   
max@0:   
max@0:   if(B_is_vec == true)
max@0:     {
max@0:     return val * op_dot::direct_dot(A.n_elem, A.mem, B.mem, C.mem);
max@0:     }
max@0:   else
max@0:     {
max@0:     return val * op_dotext::direct_rowvec_diagmat_colvec(A.mem, B, C.mem);
max@0:     }
max@0:   }
max@0: 
max@0: 
max@0: 
max@0: template<typename T1, typename T2>
max@0: arma_inline
max@0: arma_warn_unused
max@0: typename T1::elem_type
max@0: as_scalar(const Glue<T1, T2, glue_times>& X, const typename arma_not_cx<typename T1::elem_type>::result* junk = 0)
max@0:   {
max@0:   arma_extra_debug_sigprint();
max@0:   arma_ignore(junk);
max@0:   
max@0:   if(is_glue_times_diag<T1>::value == false)
max@0:     {
max@0:     const sword N_mat = 1 + depth_lhs< glue_times, Glue<T1,T2,glue_times> >::num;
max@0:     
max@0:     arma_extra_debug_print(arma_boost::format("N_mat = %d") % N_mat);
max@0:     
max@0:     return as_scalar_redirect<N_mat>::apply(X);
max@0:     }
max@0:   else
max@0:     {
max@0:     return as_scalar_diag(X);
max@0:     }
max@0:   }
max@0: 
max@0: 
max@0: 
max@0: template<typename T1>
max@0: inline
max@0: arma_warn_unused
max@0: typename T1::elem_type
max@0: as_scalar(const Base<typename T1::elem_type,T1>& X)
max@0:   {
max@0:   arma_extra_debug_sigprint();
max@0:   
max@0:   typedef typename T1::elem_type eT;
max@0:   
max@0:   const unwrap<T1>   tmp(X.get_ref());
max@0:   const Mat<eT>& A = tmp.M;
max@0:   
max@0:   arma_debug_check( (A.n_elem != 1), "as_scalar(): expression doesn't evaluate to exactly one element" );
max@0:   
max@0:   return A.mem[0];
max@0:   }
max@0: 
max@0: 
max@0: 
max@0: template<typename T1>
max@0: arma_inline
max@0: arma_warn_unused
max@0: typename T1::elem_type
max@0: as_scalar(const eOp<T1, eop_neg>& X)
max@0:   {
max@0:   arma_extra_debug_sigprint();
max@0:   
max@0:   return -(as_scalar(X.P.Q));
max@0:   }
max@0: 
max@0: 
max@0: 
max@0: template<typename T1>
max@0: inline
max@0: arma_warn_unused
max@0: typename T1::elem_type
max@0: as_scalar(const BaseCube<typename T1::elem_type,T1>& X)
max@0:   {
max@0:   arma_extra_debug_sigprint();
max@0:   
max@0:   typedef typename T1::elem_type eT;
max@0:   
max@0:   const unwrap_cube<T1> tmp(X.get_ref());
max@0:   const Cube<eT>& A   = tmp.M;
max@0:   
max@0:   arma_debug_check( (A.n_elem != 1), "as_scalar(): expression doesn't evaluate to exactly one element" );
max@0:   
max@0:   return A.mem[0];
max@0:   }
max@0: 
max@0: 
max@0: 
max@0: template<typename T>
max@0: arma_inline
max@0: arma_warn_unused
max@0: const typename arma_scalar_only<T>::result &
max@0: as_scalar(const T& x)
max@0:   {
max@0:   return x;
max@0:   }
max@0: 
max@0: 
max@0: 
max@0: //! @}