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: // Copyright (C) 2011 Stanislav Funiak
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_rank
max@0: //! @{
max@0: 
max@0: 
max@0: 
max@0: template<typename T1>
max@0: inline
max@0: arma_warn_unused
max@0: uword
max@0: rank
max@0:   (
max@0:   const Base<typename T1::elem_type,T1>& X,
max@0:         typename T1::pod_type            tol = 0.0,
max@0:   const typename arma_blas_type_only<typename T1::elem_type>::result* junk = 0
max@0:   )
max@0:   {
max@0:   arma_extra_debug_sigprint();
max@0:   arma_ignore(junk);
max@0:   
max@0:   typedef typename T1::elem_type eT;
max@0:   typedef typename T1::pod_type   T;
max@0:   
max@0:   uword    X_n_rows;
max@0:   uword    X_n_cols;
max@0:   Col<T> s;
max@0:   
max@0:   const bool status = auxlib::svd(s, X, X_n_rows, X_n_cols);
max@0:   const uword  n_elem = s.n_elem;
max@0:   
max@0:   if(status == true)
max@0:     {
max@0:     if( (tol == T(0)) && (n_elem > 0) )
max@0:       {
max@0:       tol = (std::max)(X_n_rows, X_n_cols) * eop_aux::direct_eps(max(s));
max@0:       }
max@0:     
max@0:     // count non zero valued elements in s
max@0:     
max@0:     const T*  s_mem  = s.memptr();
max@0:           uword count  = 0;
max@0:     
max@0:     for(uword i=0; i<n_elem; ++i)
max@0:       {
max@0:       if(s_mem[i] > tol)
max@0:         {
max@0:         ++count;
max@0:         }
max@0:       }
max@0:     
max@0:     return count;
max@0:     }
max@0:   else
max@0:     {
max@0:     arma_bad("rank(): failed to converge");
max@0:     
max@0:     return uword(0);
max@0:     }
max@0:   }
max@0: 
max@0: 
max@0: 
max@0: //! @}