Move into version control

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diff --git a/src/armadillo/include/armadillo_bits/diagview_meat.hpp b/src/armadillo/include/armadillo_bits/diagview_meat.hpp
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index 0000000..e35f857
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+++ b/src/armadillo/include/armadillo_bits/diagview_meat.hpp
@@ -0,0 +1,1025 @@
+// SPDX-License-Identifier: Apache-2.0
+// 
+// Copyright 2008-2016 Conrad Sanderson (http://conradsanderson.id.au)
+// Copyright 2008-2016 National ICT Australia (NICTA)
+// 
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+// http://www.apache.org/licenses/LICENSE-2.0
+// 
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// ------------------------------------------------------------------------
+
+
+//! \addtogroup diagview
+//! @{
+
+
+template<typename eT>
+inline
+diagview<eT>::~diagview()
+  {
+  arma_extra_debug_sigprint_this(this);
+  }
+
+
+
+template<typename eT>
+arma_inline
+diagview<eT>::diagview(const Mat<eT>& in_m, const uword in_row_offset, const uword in_col_offset, const uword in_len)
+  : m         (in_m         )
+  , row_offset(in_row_offset)
+  , col_offset(in_col_offset)
+  , n_rows    (in_len       )
+  , n_elem    (in_len       )
+  {
+  arma_extra_debug_sigprint_this(this);
+  }
+
+
+
+template<typename eT>
+inline
+diagview<eT>::diagview(const diagview<eT>& in)
+  : m         (in.m         )
+  , row_offset(in.row_offset)
+  , col_offset(in.col_offset)
+  , n_rows    (in.n_rows    )
+  , n_elem    (in.n_elem    )
+  {
+  arma_extra_debug_sigprint(arma_str::format("this = %x   in = %x") % this % &in);
+  }
+
+
+
+template<typename eT>
+inline
+diagview<eT>::diagview(diagview<eT>&& in)
+  : m         (in.m         )
+  , row_offset(in.row_offset)
+  , col_offset(in.col_offset)
+  , n_rows    (in.n_rows    )
+  , n_elem    (in.n_elem    )
+  {
+  arma_extra_debug_sigprint(arma_str::format("this = %x   in = %x") % this % &in);
+  
+  // for paranoia
+  
+  access::rw(in.row_offset) = 0;
+  access::rw(in.col_offset) = 0;
+  access::rw(in.n_rows    ) = 0;
+  access::rw(in.n_elem    ) = 0;
+  }
+
+
+
+//! set a diagonal of our matrix using a diagonal from a foreign matrix
+template<typename eT>
+inline
+void
+diagview<eT>::operator= (const diagview<eT>& x)
+  {
+  arma_extra_debug_sigprint();
+  
+  diagview<eT>& d = *this;
+  
+  arma_debug_check( (d.n_elem != x.n_elem), "diagview: diagonals have incompatible lengths" );
+  
+        Mat<eT>& d_m = const_cast< Mat<eT>& >(d.m);
+  const Mat<eT>& x_m = x.m;
+  
+  if(&d_m != &x_m)
+    {
+    const uword d_n_elem     = d.n_elem;
+    const uword d_row_offset = d.row_offset;
+    const uword d_col_offset = d.col_offset;
+    
+    const uword x_row_offset = x.row_offset;
+    const uword x_col_offset = x.col_offset;
+    
+    uword ii,jj;
+    for(ii=0, jj=1; jj < d_n_elem; ii+=2, jj+=2)
+      {
+      const eT tmp_i = x_m.at(ii + x_row_offset, ii + x_col_offset);
+      const eT tmp_j = x_m.at(jj + x_row_offset, jj + x_col_offset);
+      
+      d_m.at(ii + d_row_offset, ii + d_col_offset) = tmp_i;
+      d_m.at(jj + d_row_offset, jj + d_col_offset) = tmp_j;
+      }
+    
+    if(ii < d_n_elem)
+      {
+      d_m.at(ii + d_row_offset, ii + d_col_offset) = x_m.at(ii + x_row_offset, ii + x_col_offset);
+      }
+    }
+  else
+    {
+    const Mat<eT> tmp = x;
+    
+    (*this).operator=(tmp);
+    }
+  }
+
+
+
+template<typename eT>
+inline
+void
+diagview<eT>::operator+=(const eT val)
+  {
+  arma_extra_debug_sigprint();
+  
+  Mat<eT>& t_m = const_cast< Mat<eT>& >(m);
+  
+  const uword t_n_elem     = n_elem;
+  const uword t_row_offset = row_offset;
+  const uword t_col_offset = col_offset;
+  
+  for(uword ii=0; ii < t_n_elem; ++ii)
+    {
+    t_m.at( ii + t_row_offset,  ii + t_col_offset) += val;
+    }
+  }
+
+
+
+template<typename eT>
+inline
+void
+diagview<eT>::operator-=(const eT val)
+  {
+  arma_extra_debug_sigprint();
+  
+  Mat<eT>& t_m = const_cast< Mat<eT>& >(m);
+  
+  const uword t_n_elem     = n_elem;
+  const uword t_row_offset = row_offset;
+  const uword t_col_offset = col_offset;
+  
+  for(uword ii=0; ii < t_n_elem; ++ii)
+    {
+    t_m.at( ii + t_row_offset,  ii + t_col_offset) -= val;
+    }
+  }
+
+
+
+template<typename eT>
+inline
+void
+diagview<eT>::operator*=(const eT val)
+  {
+  arma_extra_debug_sigprint();
+  
+  Mat<eT>& t_m = const_cast< Mat<eT>& >(m);
+  
+  const uword t_n_elem     = n_elem;
+  const uword t_row_offset = row_offset;
+  const uword t_col_offset = col_offset;
+  
+  for(uword ii=0; ii < t_n_elem; ++ii)
+    {
+    t_m.at( ii + t_row_offset,  ii + t_col_offset) *= val;
+    }
+  }
+
+
+
+template<typename eT>
+inline
+void
+diagview<eT>::operator/=(const eT val)
+  {
+  arma_extra_debug_sigprint();
+  
+  Mat<eT>& t_m = const_cast< Mat<eT>& >(m);
+  
+  const uword t_n_elem     = n_elem;
+  const uword t_row_offset = row_offset;
+  const uword t_col_offset = col_offset;
+  
+  for(uword ii=0; ii < t_n_elem; ++ii)
+    {
+    t_m.at( ii + t_row_offset,  ii + t_col_offset) /= val;
+    }
+  }
+
+
+
+//! set a diagonal of our matrix using data from a foreign object
+template<typename eT>
+template<typename T1>
+inline
+void
+diagview<eT>::operator= (const Base<eT,T1>& o)
+  {
+  arma_extra_debug_sigprint();
+  
+  diagview<eT>& d = *this;
+  
+  Mat<eT>& d_m = const_cast< Mat<eT>& >(d.m);
+  
+  const uword d_n_elem     = d.n_elem;
+  const uword d_row_offset = d.row_offset;
+  const uword d_col_offset = d.col_offset;
+    
+  const Proxy<T1> P( o.get_ref() );
+  
+  arma_debug_check
+    (
+    ( (d_n_elem != P.get_n_elem()) || ((P.get_n_rows() != 1) && (P.get_n_cols() != 1)) ),
+    "diagview: given object has incompatible size"
+    );
+  
+  const bool is_alias = P.is_alias(d_m);
+  
+  if(is_alias)  { arma_extra_debug_print("aliasing detected"); }
+  
+  if( (is_Mat<typename Proxy<T1>::stored_type>::value) || (Proxy<T1>::use_at) || (is_alias) )
+    {
+    const unwrap_check<typename Proxy<T1>::stored_type> tmp(P.Q, is_alias);
+    const Mat<eT>& x = tmp.M;
+    
+    const eT* x_mem = x.memptr();
+    
+    uword ii,jj;
+    for(ii=0, jj=1; jj < d_n_elem; ii+=2, jj+=2)
+      {
+      const eT tmp_i = x_mem[ii];
+      const eT tmp_j = x_mem[jj];
+      
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) = tmp_i;
+      d_m.at( jj + d_row_offset,  jj + d_col_offset) = tmp_j;
+      }
+    
+    if(ii < d_n_elem)
+      {
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) = x_mem[ii];
+      }
+    }
+  else
+    {
+    typename Proxy<T1>::ea_type Pea = P.get_ea();
+      
+    uword ii,jj;
+    for(ii=0, jj=1; jj < d_n_elem; ii+=2, jj+=2)
+      {
+      const eT tmp_i = Pea[ii];
+      const eT tmp_j = Pea[jj];
+      
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) = tmp_i;
+      d_m.at( jj + d_row_offset,  jj + d_col_offset) = tmp_j;
+      }
+    
+    if(ii < d_n_elem)
+      {
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) = Pea[ii];
+      }
+    }
+  }
+
+
+
+template<typename eT>
+template<typename T1>
+inline
+void
+diagview<eT>::operator+=(const Base<eT,T1>& o)
+  {
+  arma_extra_debug_sigprint();
+  
+  diagview<eT>& d = *this;
+  
+  Mat<eT>& d_m = const_cast< Mat<eT>& >(d.m);
+  
+  const uword d_n_elem     = d.n_elem;
+  const uword d_row_offset = d.row_offset;
+  const uword d_col_offset = d.col_offset;
+    
+  const Proxy<T1> P( o.get_ref() );
+  
+  arma_debug_check
+    (
+    ( (d_n_elem != P.get_n_elem()) || ((P.get_n_rows() != 1) && (P.get_n_cols() != 1)) ),
+    "diagview: given object has incompatible size"
+    );
+  
+  const bool is_alias = P.is_alias(d_m);
+  
+  if(is_alias)  { arma_extra_debug_print("aliasing detected"); }
+  
+  if( (is_Mat<typename Proxy<T1>::stored_type>::value) || (Proxy<T1>::use_at) || (is_alias) )
+    {
+    const unwrap_check<typename Proxy<T1>::stored_type> tmp(P.Q, is_alias);
+    const Mat<eT>& x = tmp.M;
+    
+    const eT* x_mem = x.memptr();
+    
+    uword ii,jj;
+    for(ii=0, jj=1; jj < d_n_elem; ii+=2, jj+=2)
+      {
+      const eT tmp_i = x_mem[ii];
+      const eT tmp_j = x_mem[jj];
+      
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) += tmp_i;
+      d_m.at( jj + d_row_offset,  jj + d_col_offset) += tmp_j;
+      }
+    
+    if(ii < d_n_elem)
+      {
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) += x_mem[ii];
+      }
+    }
+  else
+    {
+    typename Proxy<T1>::ea_type Pea = P.get_ea();
+      
+    uword ii,jj;
+    for(ii=0, jj=1; jj < d_n_elem; ii+=2, jj+=2)
+      {
+      const eT tmp_i = Pea[ii];
+      const eT tmp_j = Pea[jj];
+      
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) += tmp_i;
+      d_m.at( jj + d_row_offset,  jj + d_col_offset) += tmp_j;
+      }
+    
+    if(ii < d_n_elem)
+      {
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) += Pea[ii];
+      }
+    }
+  }
+
+
+
+template<typename eT>
+template<typename T1>
+inline
+void
+diagview<eT>::operator-=(const Base<eT,T1>& o)
+  {
+  arma_extra_debug_sigprint();
+  
+  diagview<eT>& d = *this;
+  
+  Mat<eT>& d_m = const_cast< Mat<eT>& >(d.m);
+  
+  const uword d_n_elem     = d.n_elem;
+  const uword d_row_offset = d.row_offset;
+  const uword d_col_offset = d.col_offset;
+    
+  const Proxy<T1> P( o.get_ref() );
+  
+  arma_debug_check
+    (
+    ( (d_n_elem != P.get_n_elem()) || ((P.get_n_rows() != 1) && (P.get_n_cols() != 1)) ),
+    "diagview: given object has incompatible size"
+    );
+  
+  const bool is_alias = P.is_alias(d_m);
+  
+  if(is_alias)  { arma_extra_debug_print("aliasing detected"); }
+  
+  if( (is_Mat<typename Proxy<T1>::stored_type>::value) || (Proxy<T1>::use_at) || (is_alias) )
+    {
+    const unwrap_check<typename Proxy<T1>::stored_type> tmp(P.Q, is_alias);
+    const Mat<eT>& x = tmp.M;
+    
+    const eT* x_mem = x.memptr();
+    
+    uword ii,jj;
+    for(ii=0, jj=1; jj < d_n_elem; ii+=2, jj+=2)
+      {
+      const eT tmp_i = x_mem[ii];
+      const eT tmp_j = x_mem[jj];
+      
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) -= tmp_i;
+      d_m.at( jj + d_row_offset,  jj + d_col_offset) -= tmp_j;
+      }
+    
+    if(ii < d_n_elem)
+      {
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) -= x_mem[ii];
+      }
+    }
+  else
+    {
+    typename Proxy<T1>::ea_type Pea = P.get_ea();
+      
+    uword ii,jj;
+    for(ii=0, jj=1; jj < d_n_elem; ii+=2, jj+=2)
+      {
+      const eT tmp_i = Pea[ii];
+      const eT tmp_j = Pea[jj];
+      
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) -= tmp_i;
+      d_m.at( jj + d_row_offset,  jj + d_col_offset) -= tmp_j;
+      }
+    
+    if(ii < d_n_elem)
+      {
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) -= Pea[ii];
+      }
+    }
+  }
+
+
+
+template<typename eT>
+template<typename T1>
+inline
+void
+diagview<eT>::operator%=(const Base<eT,T1>& o)
+  {
+  arma_extra_debug_sigprint();
+  
+  diagview<eT>& d = *this;
+  
+  Mat<eT>& d_m = const_cast< Mat<eT>& >(d.m);
+  
+  const uword d_n_elem     = d.n_elem;
+  const uword d_row_offset = d.row_offset;
+  const uword d_col_offset = d.col_offset;
+    
+  const Proxy<T1> P( o.get_ref() );
+  
+  arma_debug_check
+    (
+    ( (d_n_elem != P.get_n_elem()) || ((P.get_n_rows() != 1) && (P.get_n_cols() != 1)) ),
+    "diagview: given object has incompatible size"
+    );
+  
+  const bool is_alias = P.is_alias(d_m);
+  
+  if(is_alias)  { arma_extra_debug_print("aliasing detected"); }
+  
+  if( (is_Mat<typename Proxy<T1>::stored_type>::value) || (Proxy<T1>::use_at) || (is_alias) )
+    {
+    const unwrap_check<typename Proxy<T1>::stored_type> tmp(P.Q, is_alias);
+    const Mat<eT>& x = tmp.M;
+    
+    const eT* x_mem = x.memptr();
+    
+    uword ii,jj;
+    for(ii=0, jj=1; jj < d_n_elem; ii+=2, jj+=2)
+      {
+      const eT tmp_i = x_mem[ii];
+      const eT tmp_j = x_mem[jj];
+      
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) *= tmp_i;
+      d_m.at( jj + d_row_offset,  jj + d_col_offset) *= tmp_j;
+      }
+    
+    if(ii < d_n_elem)
+      {
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) *= x_mem[ii];
+      }
+    }
+  else
+    {
+    typename Proxy<T1>::ea_type Pea = P.get_ea();
+      
+    uword ii,jj;
+    for(ii=0, jj=1; jj < d_n_elem; ii+=2, jj+=2)
+      {
+      const eT tmp_i = Pea[ii];
+      const eT tmp_j = Pea[jj];
+      
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) *= tmp_i;
+      d_m.at( jj + d_row_offset,  jj + d_col_offset) *= tmp_j;
+      }
+    
+    if(ii < d_n_elem)
+      {
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) *= Pea[ii];
+      }
+    }
+  }
+
+
+
+template<typename eT>
+template<typename T1>
+inline
+void
+diagview<eT>::operator/=(const Base<eT,T1>& o)
+  {
+  arma_extra_debug_sigprint();
+  
+  diagview<eT>& d = *this;
+  
+  Mat<eT>& d_m = const_cast< Mat<eT>& >(d.m);
+  
+  const uword d_n_elem     = d.n_elem;
+  const uword d_row_offset = d.row_offset;
+  const uword d_col_offset = d.col_offset;
+    
+  const Proxy<T1> P( o.get_ref() );
+  
+  arma_debug_check
+    (
+    ( (d_n_elem != P.get_n_elem()) || ((P.get_n_rows() != 1) && (P.get_n_cols() != 1)) ),
+    "diagview: given object has incompatible size"
+    );
+  
+  const bool is_alias = P.is_alias(d_m);
+  
+  if(is_alias)  { arma_extra_debug_print("aliasing detected"); }
+  
+  if( (is_Mat<typename Proxy<T1>::stored_type>::value) || (Proxy<T1>::use_at) || (is_alias) )
+    {
+    const unwrap_check<typename Proxy<T1>::stored_type> tmp(P.Q, is_alias);
+    const Mat<eT>& x = tmp.M;
+    
+    const eT* x_mem = x.memptr();
+    
+    uword ii,jj;
+    for(ii=0, jj=1; jj < d_n_elem; ii+=2, jj+=2)
+      {
+      const eT tmp_i = x_mem[ii];
+      const eT tmp_j = x_mem[jj];
+      
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) /= tmp_i;
+      d_m.at( jj + d_row_offset,  jj + d_col_offset) /= tmp_j;
+      }
+    
+    if(ii < d_n_elem)
+      {
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) /= x_mem[ii];
+      }
+    }
+  else
+    {
+    typename Proxy<T1>::ea_type Pea = P.get_ea();
+      
+    uword ii,jj;
+    for(ii=0, jj=1; jj < d_n_elem; ii+=2, jj+=2)
+      {
+      const eT tmp_i = Pea[ii];
+      const eT tmp_j = Pea[jj];
+      
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) /= tmp_i;
+      d_m.at( jj + d_row_offset,  jj + d_col_offset) /= tmp_j;
+      }
+    
+    if(ii < d_n_elem)
+      {
+      d_m.at( ii + d_row_offset,  ii + d_col_offset) /= Pea[ii];
+      }
+    }
+  }
+
+
+
+//! extract a diagonal and store it as a column vector
+template<typename eT>
+inline
+void
+diagview<eT>::extract(Mat<eT>& out, const diagview<eT>& in)
+  {
+  arma_extra_debug_sigprint();
+  
+  // NOTE: we're assuming that the matrix has already been set to the correct size and there is no aliasing;
+  // size setting and alias checking is done by either the Mat contructor or operator=()
+  
+  const Mat<eT>& in_m = in.m;
+  
+  const uword in_n_elem     = in.n_elem;
+  const uword in_row_offset = in.row_offset;
+  const uword in_col_offset = in.col_offset;
+  
+  eT* out_mem = out.memptr();
+  
+  uword i,j;
+  for(i=0, j=1; j < in_n_elem; i+=2, j+=2)
+    {
+    const eT tmp_i = in_m.at( i + in_row_offset, i + in_col_offset );
+    const eT tmp_j = in_m.at( j + in_row_offset, j + in_col_offset );
+    
+    out_mem[i] = tmp_i;
+    out_mem[j] = tmp_j;
+    }
+  
+  if(i < in_n_elem)
+    {
+    out_mem[i] = in_m.at( i + in_row_offset, i + in_col_offset );
+    }
+  }
+
+
+
+//! X += Y.diag()
+template<typename eT>
+inline
+void
+diagview<eT>::plus_inplace(Mat<eT>& out, const diagview<eT>& in)
+  {
+  arma_extra_debug_sigprint();
+  
+  arma_debug_assert_same_size(out.n_rows, out.n_cols, in.n_rows, in.n_cols, "addition");
+  
+  const Mat<eT>& in_m = in.m;
+  
+  const uword in_n_elem     = in.n_elem;
+  const uword in_row_offset = in.row_offset;
+  const uword in_col_offset = in.col_offset;
+  
+  eT* out_mem = out.memptr();
+  
+  uword i,j;
+  for(i=0, j=1; j < in_n_elem; i+=2, j+=2)
+    {
+    const eT tmp_i = in_m.at( i + in_row_offset, i + in_col_offset );
+    const eT tmp_j = in_m.at( j + in_row_offset, j + in_col_offset );
+    
+    out_mem[i] += tmp_i;
+    out_mem[j] += tmp_j;
+    }
+  
+  if(i < in_n_elem)
+    {
+    out_mem[i] += in_m.at( i + in_row_offset, i + in_col_offset );
+    }
+  }
+
+
+
+//! X -= Y.diag()
+template<typename eT>
+inline
+void
+diagview<eT>::minus_inplace(Mat<eT>& out, const diagview<eT>& in)
+  {
+  arma_extra_debug_sigprint();
+  
+  arma_debug_assert_same_size(out.n_rows, out.n_cols, in.n_rows, in.n_cols, "subtraction");
+  
+  const Mat<eT>& in_m = in.m;
+  
+  const uword in_n_elem     = in.n_elem;
+  const uword in_row_offset = in.row_offset;
+  const uword in_col_offset = in.col_offset;
+  
+  eT* out_mem = out.memptr();
+  
+  uword i,j;
+  for(i=0, j=1; j < in_n_elem; i+=2, j+=2)
+    {
+    const eT tmp_i = in_m.at( i + in_row_offset, i + in_col_offset );
+    const eT tmp_j = in_m.at( j + in_row_offset, j + in_col_offset );
+    
+    out_mem[i] -= tmp_i;
+    out_mem[j] -= tmp_j;
+    }
+  
+  if(i < in_n_elem)
+    {
+    out_mem[i] -= in_m.at( i + in_row_offset, i + in_col_offset );
+    }
+  }
+
+
+
+//! X %= Y.diag()
+template<typename eT>
+inline
+void
+diagview<eT>::schur_inplace(Mat<eT>& out, const diagview<eT>& in)
+  {
+  arma_extra_debug_sigprint();
+  
+  arma_debug_assert_same_size(out.n_rows, out.n_cols, in.n_rows, in.n_cols, "element-wise multiplication");
+  
+  const Mat<eT>& in_m = in.m;
+  
+  const uword in_n_elem     = in.n_elem;
+  const uword in_row_offset = in.row_offset;
+  const uword in_col_offset = in.col_offset;
+  
+  eT* out_mem = out.memptr();
+  
+  uword i,j;
+  for(i=0, j=1; j < in_n_elem; i+=2, j+=2)
+    {
+    const eT tmp_i = in_m.at( i + in_row_offset, i + in_col_offset );
+    const eT tmp_j = in_m.at( j + in_row_offset, j + in_col_offset );
+    
+    out_mem[i] *= tmp_i;
+    out_mem[j] *= tmp_j;
+    }
+  
+  if(i < in_n_elem)
+    {
+    out_mem[i] *= in_m.at( i + in_row_offset, i + in_col_offset );
+    }
+  }
+
+
+
+//! X /= Y.diag()
+template<typename eT>
+inline
+void
+diagview<eT>::div_inplace(Mat<eT>& out, const diagview<eT>& in)
+  {
+  arma_extra_debug_sigprint();
+  
+  arma_debug_assert_same_size(out.n_rows, out.n_cols, in.n_rows, in.n_cols, "element-wise division");
+  
+  const Mat<eT>& in_m = in.m;
+  
+  const uword in_n_elem     = in.n_elem;
+  const uword in_row_offset = in.row_offset;
+  const uword in_col_offset = in.col_offset;
+  
+  eT* out_mem = out.memptr();
+  
+  uword i,j;
+  for(i=0, j=1; j < in_n_elem; i+=2, j+=2)
+    {
+    const eT tmp_i = in_m.at( i + in_row_offset, i + in_col_offset );
+    const eT tmp_j = in_m.at( j + in_row_offset, j + in_col_offset );
+    
+    out_mem[i] /= tmp_i;
+    out_mem[j] /= tmp_j;
+    }
+  
+  if(i < in_n_elem)
+    {
+    out_mem[i] /= in_m.at( i + in_row_offset, i + in_col_offset );
+    }
+  }
+
+
+
+template<typename eT>
+arma_inline
+eT
+diagview<eT>::at_alt(const uword ii) const
+  {
+  return m.at(ii+row_offset, ii+col_offset);
+  }
+
+
+
+template<typename eT>
+arma_inline
+eT&
+diagview<eT>::operator[](const uword ii)
+  {
+  return (const_cast< Mat<eT>& >(m)).at(ii+row_offset, ii+col_offset);
+  }
+
+
+
+template<typename eT>
+arma_inline
+eT
+diagview<eT>::operator[](const uword ii) const
+  {
+  return m.at(ii+row_offset, ii+col_offset);
+  }
+
+
+
+template<typename eT>
+arma_inline
+eT&
+diagview<eT>::at(const uword ii)
+  {
+  return (const_cast< Mat<eT>& >(m)).at(ii+row_offset, ii+col_offset);
+  }
+
+
+
+template<typename eT>
+arma_inline
+eT
+diagview<eT>::at(const uword ii) const
+  {
+  return m.at(ii+row_offset, ii+col_offset);
+  }
+
+
+
+template<typename eT>
+arma_inline
+eT&
+diagview<eT>::operator()(const uword ii)
+  {
+  arma_debug_check_bounds( (ii >= n_elem), "diagview::operator(): out of bounds" );
+  
+  return (const_cast< Mat<eT>& >(m)).at(ii+row_offset, ii+col_offset);
+  }
+
+
+
+template<typename eT>
+arma_inline
+eT
+diagview<eT>::operator()(const uword ii) const
+  {
+  arma_debug_check_bounds( (ii >= n_elem), "diagview::operator(): out of bounds" );
+  
+  return m.at(ii+row_offset, ii+col_offset);
+  }
+
+
+
+template<typename eT>
+arma_inline
+eT&
+diagview<eT>::at(const uword row, const uword)
+  {
+  return (const_cast< Mat<eT>& >(m)).at(row+row_offset, row+col_offset);
+  }
+
+
+
+template<typename eT>
+arma_inline
+eT
+diagview<eT>::at(const uword row, const uword) const
+  {
+  return m.at(row+row_offset, row+col_offset);
+  }
+
+
+
+template<typename eT>
+arma_inline
+eT&
+diagview<eT>::operator()(const uword row, const uword col)
+  {
+  arma_debug_check_bounds( ((row >= n_elem) || (col > 0)), "diagview::operator(): out of bounds" );
+  
+  return (const_cast< Mat<eT>& >(m)).at(row+row_offset, row+col_offset);
+  }
+
+
+
+template<typename eT>
+arma_inline
+eT
+diagview<eT>::operator()(const uword row, const uword col) const
+  {
+  arma_debug_check_bounds( ((row >= n_elem) || (col > 0)), "diagview::operator(): out of bounds" );
+  
+  return m.at(row+row_offset, row+col_offset);
+  }
+
+
+
+template<typename eT>
+inline
+void
+diagview<eT>::replace(const eT old_val, const eT new_val)
+  {
+  arma_extra_debug_sigprint();
+  
+  Mat<eT>& x = const_cast< Mat<eT>& >(m);
+  
+  const uword local_n_elem = n_elem;
+  
+  if(arma_isnan(old_val))
+    {
+    for(uword ii=0; ii < local_n_elem; ++ii)
+      {
+      eT& val = x.at(ii+row_offset, ii+col_offset);
+      
+      val = (arma_isnan(val)) ? new_val : val;
+      }
+    }
+  else
+    {
+    for(uword ii=0; ii < local_n_elem; ++ii)
+      {
+      eT& val = x.at(ii+row_offset, ii+col_offset);
+      
+      val = (val == old_val) ? new_val : val;
+      }
+    }
+  }
+
+
+
+template<typename eT>
+inline
+void
+diagview<eT>::clean(const typename get_pod_type<eT>::result threshold)
+  {
+  arma_extra_debug_sigprint();
+  
+  Mat<eT> tmp(*this);
+  
+  tmp.clean(threshold);
+  
+  (*this).operator=(tmp);
+  }
+
+
+
+template<typename eT>
+inline
+void
+diagview<eT>::clamp(const eT min_val, const eT max_val)
+  {
+  arma_extra_debug_sigprint();
+  
+  Mat<eT> tmp(*this);
+  
+  tmp.clamp(min_val, max_val);
+  
+  (*this).operator=(tmp);
+  }
+
+
+
+template<typename eT>
+inline
+void
+diagview<eT>::fill(const eT val)
+  {
+  arma_extra_debug_sigprint();
+  
+  Mat<eT>& x = const_cast< Mat<eT>& >(m);
+  
+  const uword local_n_elem = n_elem;
+  
+  for(uword ii=0; ii < local_n_elem; ++ii)
+    {
+    x.at(ii+row_offset, ii+col_offset) = val;
+    }
+  }
+
+
+
+template<typename eT>
+inline
+void
+diagview<eT>::zeros()
+  {
+  arma_extra_debug_sigprint();
+  
+  (*this).fill(eT(0));
+  }
+
+
+
+template<typename eT>
+inline
+void
+diagview<eT>::ones()
+  {
+  arma_extra_debug_sigprint();
+  
+  (*this).fill(eT(1));
+  }
+
+
+
+template<typename eT>
+inline
+void
+diagview<eT>::randu()
+  {
+  arma_extra_debug_sigprint();
+  
+  Mat<eT>& x = const_cast< Mat<eT>& >(m);
+  
+  const uword local_n_elem = n_elem;
+  
+  for(uword ii=0; ii < local_n_elem; ++ii)
+    {
+    x.at(ii+row_offset, ii+col_offset) = eT(arma_rng::randu<eT>());
+    }
+  }
+
+
+
+template<typename eT>
+inline
+void
+diagview<eT>::randn()
+  {
+  arma_extra_debug_sigprint();
+  
+  Mat<eT>& x = const_cast< Mat<eT>& >(m);
+  
+  const uword local_n_elem = n_elem;
+  
+  for(uword ii=0; ii < local_n_elem; ++ii)
+    {
+    x.at(ii+row_offset, ii+col_offset) = eT(arma_rng::randn<eT>());
+    }
+  }
+
+
+
+//! @}