Chris@49: // Copyright (C) 2009-2012 NICTA (www.nicta.com.au)
Chris@49: // Copyright (C) 2009-2012 Conrad Sanderson
Chris@49: // Copyright (C) 2009-2010 Dimitrios Bouzas
Chris@49: // 
Chris@49: // This Source Code Form is subject to the terms of the Mozilla Public
Chris@49: // License, v. 2.0. If a copy of the MPL was not distributed with this
Chris@49: // file, You can obtain one at http://mozilla.org/MPL/2.0/.
Chris@49: 
Chris@49: 
Chris@49: 
Chris@49: //! \addtogroup op_shuffle
Chris@49: //! @{
Chris@49: 
Chris@49: 
Chris@49: 
Chris@49: template<typename T1>
Chris@49: inline
Chris@49: void
Chris@49: op_shuffle::apply(Mat<typename T1::elem_type>& out, const Op<T1,op_shuffle>& in)
Chris@49:   {
Chris@49:   arma_extra_debug_sigprint();
Chris@49:   
Chris@49:   typedef typename T1::elem_type eT;
Chris@49:   
Chris@49:   const unwrap<T1>   tmp(in.m);
Chris@49:   const Mat<eT>& X = tmp.M;
Chris@49:   
Chris@49:   if(X.is_empty()) { out.copy_size(X); return; }
Chris@49:   
Chris@49:   const uword dim = in.aux_uword_a;
Chris@49:   const uword N   = (dim == 0) ? X.n_rows : X.n_cols;
Chris@49:   
Chris@49:   // see "fn_sort_index.hpp" for the definition of "arma_sort_index_packet"
Chris@49:   // and the associated comparison functor
Chris@49:   std::vector< arma_sort_index_packet<int,uword> > packet_vec(N);
Chris@49:   
Chris@49:   for(uword i=0; i<N; ++i)
Chris@49:     {
Chris@49:     packet_vec[i].val   = std::rand();
Chris@49:     packet_vec[i].index = i;
Chris@49:     }
Chris@49:   
Chris@49:   arma_sort_index_helper_ascend comparator;
Chris@49: 
Chris@49:   std::sort( packet_vec.begin(), packet_vec.end(), comparator );
Chris@49:   
Chris@49:   const bool is_alias = (&out == &X);
Chris@49:   
Chris@49:   if(X.is_vec() == false)
Chris@49:     {
Chris@49:     if(is_alias == false)
Chris@49:       {
Chris@49:       arma_extra_debug_print("op_shuffle::apply(): matrix");
Chris@49:       
Chris@49:       out.copy_size(X);
Chris@49:       
Chris@49:       if(dim == 0)
Chris@49:         {
Chris@49:         for(uword i=0; i<N; ++i) { out.row(i) = X.row(packet_vec[i].index); }
Chris@49:         }
Chris@49:       else
Chris@49:         {
Chris@49:         for(uword i=0; i<N; ++i) { out.col(i) = X.col(packet_vec[i].index); }
Chris@49:         }
Chris@49:       }
Chris@49:     else  // in-place shuffle
Chris@49:       {
Chris@49:       arma_extra_debug_print("op_shuffle::apply(): in-place matrix");
Chris@49:       
Chris@49:       // reuse the val member variable of packet_vec
Chris@49:       // to indicate whether a particular row or column
Chris@49:       // has already been shuffled
Chris@49:       
Chris@49:       for(uword i=0; i<N; ++i)
Chris@49:         {
Chris@49:         packet_vec[i].val = 0;
Chris@49:         }
Chris@49:         
Chris@49:       if(dim == 0)
Chris@49:         {
Chris@49:         for(uword i=0; i<N; ++i)
Chris@49:           {
Chris@49:           if(packet_vec[i].val == 0)
Chris@49:             {
Chris@49:             const uword j = packet_vec[i].index;
Chris@49:             
Chris@49:             out.swap_rows(i, j);
Chris@49:             
Chris@49:             packet_vec[j].val = 1;
Chris@49:             }
Chris@49:           }
Chris@49:         }
Chris@49:       else
Chris@49:         {
Chris@49:         for(uword i=0; i<N; ++i)
Chris@49:           {
Chris@49:           if(packet_vec[i].val == 0)
Chris@49:             {
Chris@49:             const uword j = packet_vec[i].index;
Chris@49:             
Chris@49:             out.swap_cols(i, j);
Chris@49:             
Chris@49:             packet_vec[j].val = 1;
Chris@49:             }
Chris@49:           }
Chris@49:         }
Chris@49:       }
Chris@49:     }
Chris@49:   else  // we're dealing with a vector
Chris@49:     {
Chris@49:     if(is_alias == false)
Chris@49:       {
Chris@49:       arma_extra_debug_print("op_shuffle::apply(): vector");
Chris@49:       
Chris@49:       out.copy_size(X);
Chris@49:       
Chris@49:       if(dim == 0)
Chris@49:         {
Chris@49:         if(X.n_rows > 1)  // i.e. column vector
Chris@49:           {
Chris@49:           for(uword i=0; i<N; ++i) { out[i] = X[ packet_vec[i].index ]; }
Chris@49:           }
Chris@49:         else
Chris@49:           {
Chris@49:           out = X;
Chris@49:           }
Chris@49:         }
Chris@49:       else
Chris@49:         {
Chris@49:         if(X.n_cols > 1)  // i.e. row vector
Chris@49:           {
Chris@49:           for(uword i=0; i<N; ++i) { out[i] = X[ packet_vec[i].index ]; }
Chris@49:           }
Chris@49:         else
Chris@49:           {
Chris@49:           out = X;
Chris@49:           }
Chris@49:         }
Chris@49:       }
Chris@49:     else  // in-place shuffle
Chris@49:       {
Chris@49:       arma_extra_debug_print("op_shuffle::apply(): in-place vector");
Chris@49:       
Chris@49:       // reuse the val member variable of packet_vec
Chris@49:       // to indicate whether a particular row or column
Chris@49:       // has already been shuffled
Chris@49:       
Chris@49:       for(uword i=0; i<N; ++i)
Chris@49:         {
Chris@49:         packet_vec[i].val = 0;
Chris@49:         }
Chris@49:         
Chris@49:       if(dim == 0)
Chris@49:         {
Chris@49:         if(X.n_rows > 1)  // i.e. column vector
Chris@49:           {
Chris@49:           for(uword i=0; i<N; ++i)
Chris@49:             {
Chris@49:             if(packet_vec[i].val == 0)
Chris@49:               {
Chris@49:               const uword j = packet_vec[i].index;
Chris@49:               
Chris@49:               std::swap(out[i], out[j]);
Chris@49:               
Chris@49:               packet_vec[j].val = 1;
Chris@49:               }
Chris@49:             }
Chris@49:           }
Chris@49:         }
Chris@49:       else
Chris@49:         {
Chris@49:         if(X.n_cols > 1)  // i.e. row vector
Chris@49:           {
Chris@49:           for(uword i=0; i<N; ++i)
Chris@49:             {
Chris@49:             if(packet_vec[i].val == 0)
Chris@49:               {
Chris@49:               const uword j = packet_vec[i].index;
Chris@49:               
Chris@49:               std::swap(out[i], out[j]);
Chris@49:               
Chris@49:               packet_vec[j].val = 1;
Chris@49:               }
Chris@49:             }
Chris@49:           }
Chris@49:         }
Chris@49:       }
Chris@49:     }
Chris@49:   
Chris@49:   }
Chris@49: 
Chris@49: 
Chris@49: //! @}