comparison armadillo-2.4.4/include/armadillo_bits/op_trimat_meat.hpp @ 0:8b6102e2a9b0

Armadillo Library

+// Copyright (C) 2010-2011 NICTA (www.nicta.com.au)
+// Copyright (C) 2010-2011 Conrad Sanderson
+// Copyright (C) 2011      Ryan Curtin
+// 
+// This file is part of the Armadillo 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)
+
+
+//! \addtogroup op_trimat
+//! @{
+
+
+
+template<typename eT>
+inline
+void
+op_trimat::fill_zeros(Mat<eT>& out, const bool upper)
+  {
+  arma_extra_debug_sigprint();
+  
+  const uword N = out.n_rows;
+  
+  if(upper)
+    {
+    // upper triangular: set all elements below the diagonal to zero
+    
+    for(uword i=0; i<N; ++i)
+      {
+      eT* data = out.colptr(i);
+      
+      arrayops::inplace_set( &data[i+1], eT(0), (N-(i+1)) );
+      }
+    }
+  else
+    {
+    // lower triangular: set all elements above the diagonal to zero
+    
+    for(uword i=1; i<N; ++i)
+      {
+      eT* data = out.colptr(i);
+      
+      arrayops::inplace_set( data, eT(0), i );
+      }
+    }
+  }
+
+
+
+template<typename T1>
+inline
+void
+op_trimat::apply(Mat<typename T1::elem_type>& out, const Op<T1,op_trimat>& in)
+  {
+  arma_extra_debug_sigprint();
+  
+  typedef typename T1::elem_type eT;
+  
+  const unwrap<T1> tmp(in.m);
+  const Mat<eT>& A = tmp.M;
+  
+  arma_debug_check( (A.is_square() == false), "trimatu()/trimatl(): given matrix must be square" );
+  
+  const uword  N     = A.n_rows;
+  const bool upper = (in.aux_uword_a == 0);
+  
+  if(&out != &A)
+    {
+    out.copy_size(A);
+    
+    if(upper)
+      {
+      // upper triangular: copy the diagonal and the elements above the diagonal
+      for(uword i=0; i<N; ++i)
+        {
+        const eT* A_data   = A.colptr(i);
+              eT* out_data = out.colptr(i);
+        
+        arrayops::copy( out_data, A_data, i+1 );
+        }
+      }
+    else
+      {
+      // lower triangular: copy the diagonal and the elements below the diagonal
+      for(uword i=0; i<N; ++i)
+        {
+        const eT* A_data   = A.colptr(i);
+              eT* out_data = out.colptr(i);
+        
+        arrayops::copy( &out_data[i], &A_data[i], N-i );
+        }
+      }
+    }
+  
+  op_trimat::fill_zeros(out, upper);
+  }
+
+
+
+template<typename T1>
+inline
+void
+op_trimat::apply(Mat<typename T1::elem_type>& out, const Op<Op<T1, op_htrans>, op_trimat>& in)
+  {
+  arma_extra_debug_sigprint();
+  
+  typedef typename T1::elem_type eT;
+  
+  const unwrap<T1>   tmp(in.m.m);
+  const Mat<eT>& A = tmp.M;
+  
+  const bool upper = (in.aux_uword_a == 0);
+  
+  op_trimat::apply_htrans(out, A, upper);
+  }
+
+
+
+template<typename eT>
+inline
+void
+op_trimat::apply_htrans
+  (
+        Mat<eT>& out,
+  const Mat<eT>& A,
+  const bool     upper,
+  const typename arma_not_cx<eT>::result* junk
+  )
+  {
+  arma_extra_debug_sigprint();
+  arma_ignore(junk);
+  
+  // This specialisation is for trimatl(trans(X)) = trans(trimatu(X)) and also
+  // trimatu(trans(X)) = trans(trimatl(X)).  We want to avoid the creation of an
+  // extra temporary.
+  
+  // It doesn't matter if the input and output matrices are the same; we will
+  // pull data from the upper or lower triangular to the lower or upper
+  // triangular (respectively) and then set the rest to 0, so overwriting issues
+  // aren't present.
+  
+  arma_debug_check( (A.is_square() == false), "trimatu()/trimatl(): given matrix must be square" );
+  
+  const uword N = A.n_rows;
+  
+  if(&out != &A)
+    {
+    out.copy_size(A);
+    }
+  
+  // We can't really get away with any array copy operations here,
+  // unfortunately...
+  
+  if(upper)
+    {
+    // Upper triangular: but since we're transposing, we're taking the lower
+    // triangular and putting it in the upper half.
+    for(uword row = 0; row < N; ++row)
+      {
+      eT* out_colptr = out.colptr(row);
+      
+      for(uword col = 0; col <= row; ++col)
+        {
+        //out.at(col, row) = A.at(row, col);
+        out_colptr[col] = A.at(row, col);
+        }
+      }
+    }
+  else
+    {
+    // Lower triangular: but since we're transposing, we're taking the upper
+    // triangular and putting it in the lower half.
+    for(uword row = 0; row < N; ++row)
+      {
+      for(uword col = row; col < N; ++col)
+        {
+        out.at(col, row) = A.at(row, col);
+        }
+      }
+    }
+  
+  op_trimat::fill_zeros(out, upper);
+  }
+
+
+
+template<typename eT>
+inline
+void
+op_trimat::apply_htrans
+  (
+        Mat<eT>& out,
+  const Mat<eT>& A,
+  const bool     upper,
+  const typename arma_cx_only<eT>::result* junk
+  )
+  {
+  arma_extra_debug_sigprint();
+  arma_ignore(junk);
+  
+  arma_debug_check( (A.is_square() == false), "trimatu()/trimatl(): given matrix must be square" );
+  
+  const uword N = A.n_rows;
+  
+  if(&out != &A)
+    {
+    out.copy_size(A);
+    }
+  
+  if(upper)
+    {
+    // Upper triangular: but since we're transposing, we're taking the lower
+    // triangular and putting it in the upper half.
+    for(uword row = 0; row < N; ++row)
+      {
+      eT* out_colptr = out.colptr(row);
+      
+      for(uword col = 0; col <= row; ++col)
+        {
+        //out.at(col, row) = std::conj( A.at(row, col) );
+        out_colptr[col] = std::conj( A.at(row, col) );
+        }
+      }
+    }
+  else
+    {
+    // Lower triangular: but since we're transposing, we're taking the upper
+    // triangular and putting it in the lower half.
+    for(uword row = 0; row < N; ++row)
+      {
+      for(uword col = row; col < N; ++col)
+        {
+        out.at(col, row) = std::conj( A.at(row, col) );
+        }
+      }
+    }
+  
+  op_trimat::fill_zeros(out, upper);
+  }
+
+
+
+//! @}