max@0: // Copyright (C) 2008-2011 NICTA (www.nicta.com.au)
max@0: // Copyright (C) 2008-2011 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 op_sort
max@0: //! @{
max@0: 
max@0: 
max@0: 
max@0: template<typename eT>
max@0: class arma_ascend_sort_helper
max@0:   {
max@0:   public:
max@0:   
max@0:   arma_inline
max@0:   bool
max@0:   operator() (eT a, eT b) const
max@0:     {
max@0:     return (a < b);
max@0:     }
max@0:   };
max@0:   
max@0: 
max@0: 
max@0: template<typename eT>
max@0: class arma_descend_sort_helper
max@0:   {
max@0:   public:
max@0:   
max@0:   arma_inline
max@0:   bool
max@0:   operator() (eT a, eT b) const
max@0:     {
max@0:     return (a > b);
max@0:     }
max@0:   };
max@0:   
max@0: 
max@0: 
max@0: template<typename T>
max@0: class arma_ascend_sort_helper< std::complex<T> >
max@0:   {
max@0:   public:
max@0:   
max@0:   typedef typename std::complex<T> eT;
max@0:   
max@0:   inline
max@0:   bool
max@0:   operator() (const eT& a, const eT& b) const
max@0:     {
max@0:     return (std::abs(a) < std::abs(b));
max@0:     }
max@0:   };
max@0: 
max@0: 
max@0: 
max@0: template<typename T>
max@0: class arma_descend_sort_helper< std::complex<T> >
max@0:   {
max@0:   public:
max@0:   
max@0:   typedef typename std::complex<T> eT;
max@0:   
max@0:   inline
max@0:   bool
max@0:   operator() (const eT& a, const eT& b) const
max@0:     {
max@0:     return (std::abs(a) > std::abs(b));
max@0:     }
max@0:   };
max@0: 
max@0: 
max@0: 
max@0: template<typename eT>
max@0: inline 
max@0: void
max@0: op_sort::direct_sort(eT* X, const uword n_elem, const uword sort_type)
max@0:   {
max@0:   arma_extra_debug_sigprint();
max@0:   
max@0:   if(sort_type == 0)
max@0:     {
max@0:     arma_ascend_sort_helper<eT> comparator;
max@0:     
max@0:     std::sort(&X[0], &X[n_elem], comparator);
max@0:     }
max@0:   else
max@0:     {
max@0:     arma_descend_sort_helper<eT> comparator;
max@0:     
max@0:     std::sort(&X[0], &X[n_elem], comparator);
max@0:     }
max@0:   }
max@0: 
max@0: 
max@0: 
max@0: template<typename eT>
max@0: inline 
max@0: void
max@0: op_sort::copy_row(eT* X, const Mat<eT>& A, const uword row)
max@0:   {
max@0:   const uword N = A.n_cols;
max@0:   
max@0:   uword i,j;
max@0:   
max@0:   for(i=0, j=1; j<N; i+=2, j+=2)
max@0:     {
max@0:     X[i] = A.at(row,i);
max@0:     X[j] = A.at(row,j);
max@0:     }
max@0:   
max@0:   if(i < N)
max@0:     {
max@0:     X[i] = A.at(row,i);
max@0:     }
max@0:   }
max@0: 
max@0: 
max@0: 
max@0: template<typename eT>
max@0: inline 
max@0: void
max@0: op_sort::copy_row(Mat<eT>& A, const eT* X, const uword row)
max@0:   {
max@0:   const uword N = A.n_cols;
max@0:   
max@0:   uword i,j;
max@0:   
max@0:   for(i=0, j=1; j<N; i+=2, j+=2)
max@0:     {
max@0:     A.at(row,i) = X[i]; 
max@0:     A.at(row,j) = X[j];
max@0:     }
max@0:   
max@0:   if(i < N)
max@0:     {
max@0:     A.at(row,i) = X[i];
max@0:     }
max@0:   }
max@0: 
max@0: 
max@0: 
max@0: template<typename T1>
max@0: inline
max@0: void
max@0: op_sort::apply(Mat<typename T1::elem_type>& out, const Op<T1,op_sort>& 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:   const uword sort_type = in.aux_uword_a;
max@0:   const uword dim       = in.aux_uword_b;
max@0:   
max@0:   arma_debug_check( (sort_type > 1),          "sort(): incorrect usage. sort_type must be 0 or 1");
max@0:   arma_debug_check( (dim > 1),                "sort(): incorrect usage. dim must be 0 or 1"      );
max@0:   arma_debug_check( (X.is_finite() == false), "sort(): given object has non-finite elements"     );
max@0:   
max@0:   if( (X.n_rows * X.n_cols) <= 1 )
max@0:     {
max@0:     out = X;
max@0:     return;
max@0:     }
max@0:   
max@0:   
max@0:   if(dim == 0)  // sort the contents of each column
max@0:     {
max@0:     arma_extra_debug_print("op_sort::apply(), dim = 0");
max@0:     
max@0:     out = X;
max@0:     
max@0:     const uword n_rows = out.n_rows;
max@0:     const uword n_cols = out.n_cols;
max@0:       
max@0:     for(uword col=0; col < n_cols; ++col)
max@0:       {
max@0:       op_sort::direct_sort( out.colptr(col), n_rows, sort_type );
max@0:       }
max@0:     }
max@0:   else
max@0:   if(dim == 1)  // sort the contents of each row
max@0:     {
max@0:     if(X.n_rows == 1)  // a row vector
max@0:       {
max@0:       arma_extra_debug_print("op_sort::apply(), dim = 1, vector specific");
max@0:       
max@0:       out = X;
max@0:       op_sort::direct_sort(out.memptr(), out.n_elem, sort_type);
max@0:       }
max@0:     else  // not a row vector
max@0:       {
max@0:       arma_extra_debug_print("op_sort::apply(), dim = 1, generic");
max@0:       
max@0:       out.copy_size(X);
max@0:       
max@0:       const uword n_rows = out.n_rows;
max@0:       const uword n_cols = out.n_cols;
max@0:       
max@0:       podarray<eT> tmp_array(n_cols);
max@0:       
max@0:       for(uword row=0; row < n_rows; ++row)
max@0:         {
max@0:         op_sort::copy_row(tmp_array.memptr(), X, row);
max@0:         
max@0:         op_sort::direct_sort( tmp_array.memptr(), n_cols, sort_type );
max@0:         
max@0:         op_sort::copy_row(out, tmp_array.memptr(), row);
max@0:         }
max@0:       }
max@0:     }
max@0:   
max@0:   }
max@0: 
max@0: 
max@0: //! @}