comparison armadillo-2.4.4/include/armadillo_bits/gemv.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 gemv
+//! @{
+
+
+
+//! for tiny square matrices, size <= 4x4
+template<const bool do_trans_A=false, const bool use_alpha=false, const bool use_beta=false>
+class gemv_emul_tinysq
+  {
+  public:
+  
+  
+  template<const uword row, const uword col>
+  struct pos
+    {
+    static const uword n2 = (do_trans_A == false) ? (row + col*2) : (col + row*2);
+    static const uword n3 = (do_trans_A == false) ? (row + col*3) : (col + row*3);
+    static const uword n4 = (do_trans_A == false) ? (row + col*4) : (col + row*4);
+    };
+  
+  
+  
+  template<typename eT, const uword i>
+  arma_hot
+  arma_inline
+  static
+  void
+  assign(eT* y, const eT acc, const eT alpha, const eT beta)
+    {
+    if(use_beta == false)
+      {
+      y[i] = (use_alpha == false) ? acc : alpha*acc;
+      }
+    else
+      {
+      const eT tmp = y[i];
+      
+      y[i] = beta*tmp + ( (use_alpha == false) ? acc : alpha*acc );
+      }
+    }
+  
+  
+
+  template<typename eT>
+  arma_hot
+  inline
+  static
+  void
+  apply( eT* y, const Mat<eT>& A, const eT* x, const eT alpha = eT(1), const eT beta = eT(0) )
+    {
+    arma_extra_debug_sigprint();
+    
+    const eT*  Am = A.memptr();
+    
+    switch(A.n_rows)
+      {
+      case 1:
+        {
+        const eT acc = Am[0] * x[0];
+        
+        assign<eT, 0>(y, acc, alpha, beta);
+        }
+        break;
+      
+      
+      case 2:
+        {
+        const eT x0 = x[0];
+        const eT x1 = x[1];
+        
+        const eT acc0 = Am[pos<0,0>::n2]*x0 + Am[pos<0,1>::n2]*x1;
+        const eT acc1 = Am[pos<1,0>::n2]*x0 + Am[pos<1,1>::n2]*x1;
+        
+        assign<eT, 0>(y, acc0, alpha, beta);
+        assign<eT, 1>(y, acc1, alpha, beta);
+        }
+        break;
+      
+        
+      case 3:
+        {
+        const eT x0 = x[0];
+        const eT x1 = x[1];
+        const eT x2 = x[2];
+        
+        const eT acc0 = Am[pos<0,0>::n3]*x0 + Am[pos<0,1>::n3]*x1 + Am[pos<0,2>::n3]*x2;
+        const eT acc1 = Am[pos<1,0>::n3]*x0 + Am[pos<1,1>::n3]*x1 + Am[pos<1,2>::n3]*x2;
+        const eT acc2 = Am[pos<2,0>::n3]*x0 + Am[pos<2,1>::n3]*x1 + Am[pos<2,2>::n3]*x2;
+        
+        assign<eT, 0>(y, acc0, alpha, beta);
+        assign<eT, 1>(y, acc1, alpha, beta);
+        assign<eT, 2>(y, acc2, alpha, beta);
+        }
+        break;
+      
+      
+      case 4:
+        {
+        const eT x0 = x[0];
+        const eT x1 = x[1];
+        const eT x2 = x[2];
+        const eT x3 = x[3];
+        
+        const eT acc0 = Am[pos<0,0>::n4]*x0 + Am[pos<0,1>::n4]*x1 + Am[pos<0,2>::n4]*x2 + Am[pos<0,3>::n4]*x3;
+        const eT acc1 = Am[pos<1,0>::n4]*x0 + Am[pos<1,1>::n4]*x1 + Am[pos<1,2>::n4]*x2 + Am[pos<1,3>::n4]*x3;
+        const eT acc2 = Am[pos<2,0>::n4]*x0 + Am[pos<2,1>::n4]*x1 + Am[pos<2,2>::n4]*x2 + Am[pos<2,3>::n4]*x3;
+        const eT acc3 = Am[pos<3,0>::n4]*x0 + Am[pos<3,1>::n4]*x1 + Am[pos<3,2>::n4]*x2 + Am[pos<3,3>::n4]*x3;
+        
+        assign<eT, 0>(y, acc0, alpha, beta);
+        assign<eT, 1>(y, acc1, alpha, beta);
+        assign<eT, 2>(y, acc2, alpha, beta);
+        assign<eT, 3>(y, acc3, alpha, beta);
+        }
+        break;
+      
+      
+      default:
+        ;
+      }
+    }
+    
+  };
+
+
+
+//! \brief
+//! Partial emulation of ATLAS/BLAS gemv().
+//! 'y' is assumed to have been set to the correct size (i.e. taking into account the transpose)
+
+template<const bool do_trans_A=false, const bool use_alpha=false, const bool use_beta=false>
+class gemv_emul_large
+  {
+  public:
+  
+  template<typename eT>
+  arma_hot
+  inline
+  static
+  void
+  apply( eT* y, const Mat<eT>& A, const eT* x, const eT alpha = eT(1), const eT beta = eT(0) )
+    {
+    arma_extra_debug_sigprint();
+    
+    const uword A_n_rows = A.n_rows;
+    const uword A_n_cols = A.n_cols;
+    
+    if(do_trans_A == false)
+      {
+      if(A_n_rows == 1)
+        {
+        const eT acc = op_dot::direct_dot_arma(A_n_cols, A.mem, x);
+        
+        if( (use_alpha == false) && (use_beta == false) )
+          {
+          y[0] = acc;
+          }
+        else
+        if( (use_alpha == true) && (use_beta == false) )
+          {
+          y[0] = alpha * acc;
+          }
+        else
+        if( (use_alpha == false) && (use_beta == true) )
+          {
+          y[0] = acc + beta*y[0];
+          }
+        else
+        if( (use_alpha == true) && (use_beta == true) )
+          {
+          y[0] = alpha*acc + beta*y[0];
+          }
+        }
+      else
+      for(uword row=0; row < A_n_rows; ++row)
+        {
+        eT acc = eT(0);
+        
+        for(uword i=0; i < A_n_cols; ++i)
+          {
+          acc += A.at(row,i) * x[i];
+          }
+        
+        if( (use_alpha == false) && (use_beta == false) )
+          {
+          y[row] = acc;
+          }
+        else
+        if( (use_alpha == true) && (use_beta == false) )
+          {
+          y[row] = alpha * acc;
+          }
+        else
+        if( (use_alpha == false) && (use_beta == true) )
+          {
+          y[row] = acc + beta*y[row];
+          }
+        else
+        if( (use_alpha == true) && (use_beta == true) )
+          {
+          y[row] = alpha*acc + beta*y[row];
+          }
+        }
+      }
+    else
+    if(do_trans_A == true)
+      {
+      for(uword col=0; col < A_n_cols; ++col)
+        {
+        // col is interpreted as row when storing the results in 'y'
+        
+        
+        // const eT* A_coldata = A.colptr(col);
+        // 
+        // eT acc = eT(0);
+        // for(uword row=0; row < A_n_rows; ++row)
+        //   {
+        //   acc += A_coldata[row] * x[row];
+        //   }
+        
+        const eT acc = op_dot::direct_dot_arma(A_n_rows, A.colptr(col), x);
+        
+        if( (use_alpha == false) && (use_beta == false) )
+          {
+          y[col] = acc;
+          }
+        else
+        if( (use_alpha == true) && (use_beta == false) )
+          {
+          y[col] = alpha * acc;
+          }
+        else
+        if( (use_alpha == false) && (use_beta == true) )
+          {
+          y[col] = acc + beta*y[col];
+          }
+        else
+        if( (use_alpha == true) && (use_beta == true) )
+          {
+          y[col] = alpha*acc + beta*y[col];
+          }
+        
+        }
+      }
+    }
+  
+  };
+
+
+
+template<const bool do_trans_A=false, const bool use_alpha=false, const bool use_beta=false>
+class gemv_emul
+  {
+  public:
+  
+  template<typename eT>
+  arma_hot
+  inline
+  static
+  void
+  apply( eT* y, const Mat<eT>& A, const eT* x, const eT alpha = eT(1), const eT beta = eT(0), const typename arma_not_cx<eT>::result* junk = 0 )
+    {
+    arma_extra_debug_sigprint();
+    arma_ignore(junk);
+    
+    const uword A_n_rows = A.n_rows;
+    const uword A_n_cols = A.n_cols;
+    
+    if( (A_n_rows <= 4) && (A_n_rows == A_n_cols) )
+      {
+      gemv_emul_tinysq<do_trans_A, use_alpha, use_beta>::apply(y, A, x, alpha, beta);
+      }
+    else
+      {
+      gemv_emul_large<do_trans_A, use_alpha, use_beta>::apply(y, A, x, alpha, beta);
+      }
+    }
+  
+  
+  
+  template<typename eT>
+  arma_hot
+  inline
+  static
+  void
+  apply( eT* y, const Mat<eT>& A, const eT* x, const eT alpha = eT(1), const eT beta = eT(0), const typename arma_cx_only<eT>::result* junk = 0 )
+    {
+    arma_extra_debug_sigprint();
+    
+    Mat<eT> tmp_A;
+    
+    if(do_trans_A)
+      {
+      op_htrans::apply_noalias(tmp_A, A);
+      }
+    
+    const Mat<eT>& AA = (do_trans_A == false) ? A : tmp_A;
+    
+    const uword AA_n_rows = AA.n_rows;
+    const uword AA_n_cols = AA.n_cols;
+    
+    if( (AA_n_rows <= 4) && (AA_n_rows == AA_n_cols) )
+      {
+      gemv_emul_tinysq<false, use_alpha, use_beta>::apply(y, AA, x, alpha, beta);
+      }
+    else
+      {
+      gemv_emul_large<false, use_alpha, use_beta>::apply(y, AA, x, alpha, beta);
+      }
+    }
+  };
+
+
+
+//! \brief
+//! Wrapper for ATLAS/BLAS gemv function, using template arguments to control the arguments passed to gemv.
+//! 'y' is assumed to have been set to the correct size (i.e. taking into account the transpose)
+
+template<const bool do_trans_A=false, const bool use_alpha=false, const bool use_beta=false>
+class gemv
+  {
+  public:
+  
+  template<typename eT>
+  inline
+  static
+  void
+  apply_blas_type( eT* y, const Mat<eT>& A, const eT* x, const eT alpha = eT(1), const eT beta = eT(0) )
+    {
+    arma_extra_debug_sigprint();
+    
+    if(A.n_elem <= 64u)
+      {
+      gemv_emul<do_trans_A, use_alpha, use_beta>::apply(y,A,x,alpha,beta);
+      }
+    else
+      {
+      #if defined(ARMA_USE_ATLAS)
+        {
+        arma_extra_debug_print("atlas::cblas_gemv()");
+        
+        atlas::cblas_gemv<eT>
+          (
+          atlas::CblasColMajor,
+          (do_trans_A) ? ( is_complex<eT>::value ? CblasConjTrans : atlas::CblasTrans ) : atlas::CblasNoTrans,
+          A.n_rows,
+          A.n_cols,
+          (use_alpha) ? alpha : eT(1),
+          A.mem,
+          A.n_rows,
+          x,
+          1,
+          (use_beta) ? beta : eT(0),
+          y,
+          1
+          );
+        }
+      #elif defined(ARMA_USE_BLAS)
+        {
+        arma_extra_debug_print("blas::gemv()");
+        
+        const char      trans_A     = (do_trans_A) ? ( is_complex<eT>::value ? 'C' : 'T' ) : 'N';
+        const blas_int  m           = A.n_rows;
+        const blas_int  n           = A.n_cols;
+        const eT        local_alpha = (use_alpha) ? alpha : eT(1);
+        //const blas_int  lda         = A.n_rows;
+        const blas_int  inc         = 1;
+        const eT        local_beta  = (use_beta) ? beta : eT(0);
+        
+        arma_extra_debug_print( arma_boost::format("blas::gemv(): trans_A = %c") % trans_A );
+        
+        blas::gemv<eT>
+          (
+          &trans_A,
+          &m,
+          &n,
+          &local_alpha,
+          A.mem,
+          &m,  // lda
+          x,
+          &inc,
+          &local_beta,
+          y,
+          &inc
+          );
+        }
+      #else
+        {
+        gemv_emul<do_trans_A, use_alpha, use_beta>::apply(y,A,x,alpha,beta);
+        }
+      #endif
+      }
+    
+    }
+  
+  
+  
+  template<typename eT>
+  arma_inline
+  static
+  void
+  apply( eT* y, const Mat<eT>& A, const eT* x, const eT alpha = eT(1), const eT beta = eT(0) )
+    {
+    gemv_emul<do_trans_A, use_alpha, use_beta>::apply(y,A,x,alpha,beta);
+    }
+  
+  
+  
+  arma_inline
+  static
+  void
+  apply
+    (
+          float*      y,
+    const Mat<float>& A,
+    const float*      x,
+    const float       alpha = float(1),
+    const float       beta  = float(0)
+    )
+    {
+    gemv<do_trans_A, use_alpha, use_beta>::apply_blas_type(y,A,x,alpha,beta);
+    }
+
+
+  
+  arma_inline
+  static
+  void
+  apply
+    (
+          double*      y,
+    const Mat<double>& A,
+    const double*      x,
+    const double       alpha = double(1),
+    const double       beta  = double(0)
+    )
+    {
+    gemv<do_trans_A, use_alpha, use_beta>::apply_blas_type(y,A,x,alpha,beta);
+    }
+
+
+  
+  arma_inline
+  static
+  void
+  apply
+    (
+          std::complex<float>*         y,
+    const Mat< std::complex<float > >& A,
+    const std::complex<float>*         x,
+    const std::complex<float>          alpha = std::complex<float>(1),
+    const std::complex<float>          beta  = std::complex<float>(0)
+    )
+    {
+    gemv<do_trans_A, use_alpha, use_beta>::apply_blas_type(y,A,x,alpha,beta);
+    }
+
+
+  
+  arma_inline
+  static
+  void
+  apply
+    (
+          std::complex<double>*        y,
+    const Mat< std::complex<double> >& A,
+    const std::complex<double>*        x,
+    const std::complex<double>         alpha = std::complex<double>(1),
+    const std::complex<double>         beta  = std::complex<double>(0)
+    )
+    {
+    gemv<do_trans_A, use_alpha, use_beta>::apply_blas_type(y,A,x,alpha,beta);
+    }
+
+
+  
+  };
+
+
+//! @}