fn_sparse_to_dense.hpp

Go to the documentation of this file.

// Copyright (C) 2011 the authors listed below
// http://ecocpak.sourceforge.net
// 
// Authors:
// - Dimitrios Bouzas (bouzas at ieee dot org)
// - Nikolaos Arvanitopoulos (niarvani at ieee dot org)
// - Anastasios Tefas (tefas at aiia dot csd dot auth dot gr)
// 
// This file is part of the ECOC PAK C++ library. It is 
// provided without any warranty of fitness for any purpose.
//
// You can redistribute this file and/or modify it under 
// the terms of the GNU Lesser General Public License (LGPL) 
// as published by the Free Software Foundation, either 
// version 3 of the License or (at your option) any later 
// version.
// (see http://www.opensource.org/licenses for more info)





mat
sparse_to_dense
  (
        struct svm_node** const X,
        const u32 n_rows,
        const u32 n_cols
  )
  {
  // allocate space for dense matrix representation
  mat dense_matrix = zeros<mat>(n_rows, n_cols);
  
  // for each row of X
  for(u32 i = 0; i < n_rows; i++)
    {  
    struct svm_node* tmp_node = const_cast<struct svm_node*>(X[i]);
    
    while(tmp_node->index != -1)
      {
      dense_matrix(i, tmp_node->index - 1) = tmp_node->value;
      tmp_node++;
      }
      
    }
 
  return dense_matrix; 
  }