max@0: // Copyright (C) 2009-2011 NICTA (www.nicta.com.au)
max@0: // Copyright (C) 2009-2011 Conrad Sanderson
max@0: // Copyright (C) 2009-2010 Dimitrios Bouzas
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: 
max@0: //! \addtogroup op_shuffle
max@0: //! @{
max@0: 
max@0: 
max@0: 
max@0: template<typename T1>
max@0: inline
max@0: void
max@0: op_shuffle::apply(Mat<typename T1::elem_type>& out, const Op<T1,op_shuffle>& in)
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(in.m);
max@0:   const Mat<eT>& X = tmp.M;
max@0:   
max@0:   if(X.is_empty())
max@0:     {
max@0:     out.copy_size(X);
max@0:     return;
max@0:     }
max@0:   
max@0:   const uword dim = in.aux_uword_a;
max@0:   const uword N   = (dim == 0) ? X.n_rows : X.n_cols;
max@0:   
max@0:   // see "fn_sort_index.hpp" for the definition of "arma_sort_index_packet_ascend"
max@0:   // and the associated "operator<"
max@0:   std::vector< arma_sort_index_packet_ascend<int,uword> > packet_vec(N);
max@0:   
max@0:   for(uword i=0; i<N; ++i)
max@0:     {
max@0:     packet_vec[i].val   = std::rand();
max@0:     packet_vec[i].index = i;
max@0:     }
max@0:   
max@0:   std::sort( packet_vec.begin(), packet_vec.end() );
max@0:   
max@0:   if(X.is_vec() == false)
max@0:     {
max@0:     if(&out != &X)
max@0:       {
max@0:       arma_extra_debug_print("op_shuffle::apply(): matrix");
max@0:       
max@0:       out.copy_size(X);
max@0:       
max@0:       if(dim == 0)
max@0:         {
max@0:         for(uword i=0; i<N; ++i)
max@0:           {
max@0:           out.row(i) = X.row(packet_vec[i].index);
max@0:           }
max@0:         }
max@0:       else
max@0:         {
max@0:         for(uword i=0; i<N; ++i)
max@0:           {
max@0:           out.col(i) = X.col(packet_vec[i].index);
max@0:           }
max@0:         }
max@0:       }
max@0:     else  // in-place shuffle
max@0:       {
max@0:       arma_extra_debug_print("op_shuffle::apply(): in-place matrix");
max@0:       
max@0:       // reuse the val member variable of packet_vec
max@0:       // to indicate whether a particular row or column
max@0:       // has already been shuffled
max@0:       
max@0:       for(uword i=0; i<N; ++i)
max@0:         {
max@0:         packet_vec[i].val = 0;
max@0:         }
max@0:         
max@0:       if(dim == 0)
max@0:         {
max@0:         for(uword i=0; i<N; ++i)
max@0:           {
max@0:           if(packet_vec[i].val == 0)
max@0:             {
max@0:             const uword j = packet_vec[i].index;
max@0:             
max@0:             out.swap_rows(i, j);
max@0:             
max@0:             packet_vec[j].val = 1;
max@0:             }
max@0:           }
max@0:         }
max@0:       else
max@0:         {
max@0:         for(uword i=0; i<N; ++i)
max@0:           {
max@0:           if(packet_vec[i].val == 0)
max@0:             {
max@0:             const uword j = packet_vec[i].index;
max@0:             
max@0:             out.swap_cols(i, j);
max@0:             
max@0:             packet_vec[j].val = 1;
max@0:             }
max@0:           }
max@0:         }
max@0:       }
max@0:     }
max@0:   else  // we're dealing with a vector
max@0:     {
max@0:     if(&out != &X)
max@0:       {
max@0:       arma_extra_debug_print("op_shuffle::apply(): vector");
max@0:       
max@0:       out.copy_size(X);
max@0:       
max@0:       if(dim == 0)
max@0:         {
max@0:         if(X.n_rows > 1)  // i.e. column vector
max@0:           {
max@0:           for(uword i=0; i<N; ++i)
max@0:             {
max@0:             out[i] = X[ packet_vec[i].index ];
max@0:             }
max@0:           }
max@0:         else
max@0:           {
max@0:           out = X;
max@0:           }
max@0:         }
max@0:       else
max@0:         {
max@0:         if(X.n_cols > 1)  // i.e. row vector
max@0:           {
max@0:           for(uword i=0; i<N; ++i)
max@0:             {
max@0:             out[i] = X[ packet_vec[i].index ];
max@0:             }
max@0:           }
max@0:         else
max@0:           {
max@0:           out = X;
max@0:           }
max@0:         }
max@0:       }
max@0:     else  // in-place shuffle
max@0:       {
max@0:       arma_extra_debug_print("op_shuffle::apply(): in-place vector");
max@0:       
max@0:       // reuse the val member variable of packet_vec
max@0:       // to indicate whether a particular row or column
max@0:       // has already been shuffled
max@0:       
max@0:       for(uword i=0; i<N; ++i)
max@0:         {
max@0:         packet_vec[i].val = 0;
max@0:         }
max@0:         
max@0:       if(dim == 0)
max@0:         {
max@0:         if(X.n_rows > 1)  // i.e. column vector
max@0:           {
max@0:           for(uword i=0; i<N; ++i)
max@0:             {
max@0:             if(packet_vec[i].val == 0)
max@0:               {
max@0:               const uword j = packet_vec[i].index;
max@0:               
max@0:               std::swap(out[i], out[j]);
max@0:               
max@0:               packet_vec[j].val = 1;
max@0:               }
max@0:             }
max@0:           }
max@0:         }
max@0:       else
max@0:         {
max@0:         if(X.n_cols > 1)  // i.e. row vector
max@0:           {
max@0:           for(uword i=0; i<N; ++i)
max@0:             {
max@0:             if(packet_vec[i].val == 0)
max@0:               {
max@0:               const uword j = packet_vec[i].index;
max@0:               
max@0:               std::swap(out[i], out[j]);
max@0:               
max@0:               packet_vec[j].val = 1;
max@0:               }
max@0:             }
max@0:           }
max@0:         }
max@0:       }
max@0:     }
max@0:   
max@0:   }
max@0: 
max@0: 
max@0: //! @}