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

Armadillo Library

+// Copyright (C) 2008-2011 NICTA (www.nicta.com.au)
+// Copyright (C) 2008-2011 Conrad Sanderson
+// 
+// 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_strans
+//! @{
+
+
+
+//! for tiny square matrices (size <= 4x4)
+template<typename eT>
+inline
+void
+op_strans::apply_noalias_tinysq(Mat<eT>& out, const Mat<eT>& A)
+  {
+  const eT* Am   = A.memptr();
+        eT* outm = out.memptr();
+  
+  switch(A.n_rows)
+    {
+    case 1:
+      {
+      outm[0] = Am[0];
+      }
+      break;
+      
+    case 2:
+      {
+      outm[pos<false,0,0>::n2] = Am[pos<true,0,0>::n2];
+      outm[pos<false,1,0>::n2] = Am[pos<true,1,0>::n2];
+      
+      outm[pos<false,0,1>::n2] = Am[pos<true,0,1>::n2];
+      outm[pos<false,1,1>::n2] = Am[pos<true,1,1>::n2];
+      }
+      break;
+    
+    case 3:
+      {
+      outm[pos<false,0,0>::n3] = Am[pos<true,0,0>::n3];
+      outm[pos<false,1,0>::n3] = Am[pos<true,1,0>::n3];
+      outm[pos<false,2,0>::n3] = Am[pos<true,2,0>::n3];
+      
+      outm[pos<false,0,1>::n3] = Am[pos<true,0,1>::n3];
+      outm[pos<false,1,1>::n3] = Am[pos<true,1,1>::n3];
+      outm[pos<false,2,1>::n3] = Am[pos<true,2,1>::n3];
+      
+      outm[pos<false,0,2>::n3] = Am[pos<true,0,2>::n3];
+      outm[pos<false,1,2>::n3] = Am[pos<true,1,2>::n3];
+      outm[pos<false,2,2>::n3] = Am[pos<true,2,2>::n3];
+      }
+      break;
+    
+    case 4:
+      {
+      outm[pos<false,0,0>::n4] = Am[pos<true,0,0>::n4];
+      outm[pos<false,1,0>::n4] = Am[pos<true,1,0>::n4];
+      outm[pos<false,2,0>::n4] = Am[pos<true,2,0>::n4];
+      outm[pos<false,3,0>::n4] = Am[pos<true,3,0>::n4];
+      
+      outm[pos<false,0,1>::n4] = Am[pos<true,0,1>::n4];
+      outm[pos<false,1,1>::n4] = Am[pos<true,1,1>::n4];
+      outm[pos<false,2,1>::n4] = Am[pos<true,2,1>::n4];
+      outm[pos<false,3,1>::n4] = Am[pos<true,3,1>::n4];
+      
+      outm[pos<false,0,2>::n4] = Am[pos<true,0,2>::n4];
+      outm[pos<false,1,2>::n4] = Am[pos<true,1,2>::n4];
+      outm[pos<false,2,2>::n4] = Am[pos<true,2,2>::n4];
+      outm[pos<false,3,2>::n4] = Am[pos<true,3,2>::n4];
+      
+      outm[pos<false,0,3>::n4] = Am[pos<true,0,3>::n4];
+      outm[pos<false,1,3>::n4] = Am[pos<true,1,3>::n4];
+      outm[pos<false,2,3>::n4] = Am[pos<true,2,3>::n4];
+      outm[pos<false,3,3>::n4] = Am[pos<true,3,3>::n4];
+      }
+      break;
+    
+    default:
+      ;
+    }
+  
+  }
+
+
+
+//! Immediate transpose of a dense matrix
+template<typename eT>
+inline
+void
+op_strans::apply_noalias(Mat<eT>& out, const Mat<eT>& A)
+  {
+  arma_extra_debug_sigprint();
+  
+  const uword A_n_cols = A.n_cols;
+  const uword A_n_rows = A.n_rows;
+  
+  out.set_size(A_n_cols, A_n_rows);
+  
+  if( (A_n_cols == 1) || (A_n_rows == 1) )
+    {
+    arrayops::copy( out.memptr(), A.mem, A.n_elem );
+    }
+  else
+    {
+    if( (A_n_rows <= 4) && (A_n_rows == A_n_cols) )
+      {
+      op_strans::apply_noalias_tinysq(out, A);
+      }
+    else
+      {
+      for(uword k=0; k < A_n_cols; ++k)
+        {
+        uword i, j;
+        
+        const eT* colptr = A.colptr(k);
+        
+        for(i=0, j=1; j < A_n_rows; i+=2, j+=2)
+          {
+          const eT tmp_i = colptr[i];
+          const eT tmp_j = colptr[j];
+          
+          out.at(k, i) = tmp_i;
+          out.at(k, j) = tmp_j;
+          }
+        
+        if(i < A_n_rows)
+          {
+          out.at(k, i) = colptr[i];
+          }
+        }
+      }
+    }
+  }
+
+
+
+template<typename eT>
+inline
+void
+op_strans::apply(Mat<eT>& out, const Mat<eT>& A)
+  {
+  arma_extra_debug_sigprint();
+  
+  if(&out != &A)
+    {
+    op_strans::apply_noalias(out, A);
+    }
+  else
+    {
+    const uword n_rows = out.n_rows;
+    const uword n_cols = out.n_cols;
+      
+    if(n_rows == n_cols)
+      {
+      arma_extra_debug_print("op_strans::apply(): doing in-place transpose of a square matrix");
+      
+      const uword N = n_rows;
+      
+      for(uword k=0; k < N; ++k)
+        {
+        eT* colptr = out.colptr(k);
+        
+        uword i,j;
+        
+        for(i=(k+1), j=(k+2); j < N; i+=2, j+=2)
+          {
+          std::swap(out.at(k,i), colptr[i]);
+          std::swap(out.at(k,j), colptr[j]);
+          }
+        
+        if(i < N)
+          {
+          std::swap(out.at(k,i), colptr[i]);
+          }
+        }
+      }
+    else
+      {
+      Mat<eT> tmp;
+      op_strans::apply_noalias(tmp, A);
+      
+      out.steal_mem(tmp);
+      }
+    }
+  }
+
+
+
+template<typename T1>
+inline
+void
+op_strans::apply(Mat<typename T1::elem_type>& out, const Op<T1,op_strans>& in)
+  {
+  arma_extra_debug_sigprint();
+  
+  typedef typename T1::elem_type eT;
+  
+  const unwrap<T1>   tmp(in.m);
+  const Mat<eT>& A = tmp.M;
+  
+  op_strans::apply(out, A);
+  }
+
+
+
+// inline void op_strans::apply_inplace(mat &X)
+//   {
+//   arma_extra_debug_sigprint();
+//   
+//   if((X.n_rows == 1) || (X.n_cols == 1))
+//     {
+//     const uword old_n_rows = X.n_rows;
+//     access::rw(X.n_rows) = X.n_cols;
+//     access::rw(X.n_cols) = old_n_rows;
+//     }
+//   else
+//   if(X.n_rows == X.n_cols)
+//     {
+//     for(uword col=0; col < X.n_cols; ++col)
+//       {
+//       double* X_coldata = X.colptr(col);
+//       
+//       for(uword row=(col+1); row < X.n_rows; ++row)
+//         {
+//         std::swap( A.at(col,row), A_coldata[row] );
+//         }
+//       }
+//     }
+//   else
+//     {
+//     mat tmp = trans(X);
+//     
+//     if(X.mem != X.mem_local)
+//       {
+//       double* old_mem = X.memptr();
+//       access::rw(X.mem) = tmp.memptr();
+//       access::rw(tmp.mem) = old_mem;
+//       }
+//     else
+//       {
+//       X = tmp;
+//       }
+//     }
+//   
+//   }
+
+
+
+
+//! @}