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diff --git a/src/armadillo/include/armadillo_bits/op_powmat_meat.hpp b/src/armadillo/include/armadillo_bits/op_powmat_meat.hpp
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index 0000000..323db32
--- /dev/null
+++ b/src/armadillo/include/armadillo_bits/op_powmat_meat.hpp
@@ -0,0 +1,261 @@
+// 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 op_powmat
+//! @{
+
+
+template<typename T1>
+inline
+void
+op_powmat::apply(Mat<typename T1::elem_type>& out, const Op<T1, op_powmat>& expr)
+  {
+  arma_extra_debug_sigprint();
+  
+  const uword y     =  expr.aux_uword_a;
+  const bool  y_neg = (expr.aux_uword_b == uword(1));
+  
+  const bool status = op_powmat::apply_direct(out, expr.m, y, y_neg);
+  
+  if(status == false)
+    {
+    out.soft_reset();
+    arma_stop_runtime_error("powmat(): transformation failed");
+    }
+  }
+
+
+
+template<typename T1>
+inline
+bool
+op_powmat::apply_direct(Mat<typename T1::elem_type>& out, const Base<typename T1::elem_type,T1>& X, const uword y, const bool y_neg)
+  {
+  arma_extra_debug_sigprint();
+  
+  typedef typename T1::elem_type eT;
+  
+  if(y_neg)
+    {
+    if(y == uword(1))
+      {
+      return op_inv_gen_default::apply_direct(out, X.get_ref(), "powmat()");
+      }
+    else
+      {
+      Mat<eT> X_inv;
+      
+      const bool inv_status = op_inv_gen_default::apply_direct(X_inv, X.get_ref(), "powmat()");
+      
+      if(inv_status == false)  { return false; }
+      
+      op_powmat::apply_direct_positive(out, X_inv, y);
+      }
+    }
+  else
+    {
+    const quasi_unwrap<T1> U(X.get_ref());
+    
+    arma_debug_check( (U.M.is_square() == false), "powmat(): given matrix must be square sized" );
+    
+    op_powmat::apply_direct_positive(out, U.M, y);
+    }
+  
+  return true;
+  }
+
+
+
+template<typename eT>
+inline
+void
+op_powmat::apply_direct_positive(Mat<eT>& out, const Mat<eT>& X, const uword y)
+  {
+  arma_extra_debug_sigprint();
+  
+  const uword N = X.n_rows;
+  
+  if(y == uword(0))  { out.eye(N,N); return; }
+  if(y == uword(1))  { out = X;      return; }
+  
+  if(X.is_diagmat())
+    {
+    arma_extra_debug_print("op_powmat: detected diagonal matrix");
+    
+    podarray<eT> tmp(N);  // use temporary array in case we have aliasing
+    
+    for(uword i=0; i<N; ++i)  { tmp[i] = eop_aux::pow(X.at(i,i), int(y)); }
+    
+    out.zeros(N,N);
+    
+    for(uword i=0; i<N; ++i)  { out.at(i,i) = tmp[i]; }
+    }
+  else
+    {
+         if(y == uword(2))  {                          out = X*X;       }
+    else if(y == uword(3))  { const Mat<eT> tmp = X*X; out = X*tmp;     }
+    else if(y == uword(4))  { const Mat<eT> tmp = X*X; out =   tmp*tmp; }
+    else if(y == uword(5))  { const Mat<eT> tmp = X*X; out = X*tmp*tmp; }
+    else
+      {
+      Mat<eT> tmp = X;
+      
+      out = X;
+      
+      uword z = y-1;
+      
+      while(z > 0)
+        {
+        if(z & 1)  { out = tmp * out; }
+        
+        z /= uword(2);
+        
+        if(z > 0)  { tmp = tmp * tmp; }
+        }
+      }
+    }
+  }
+
+
+
+template<typename T1>
+inline
+void
+op_powmat_cx::apply(Mat< std::complex<typename T1::pod_type> >& out, const mtOp<std::complex<typename T1::pod_type>,T1,op_powmat_cx>& expr)
+  {
+  arma_extra_debug_sigprint();
+  
+  typedef typename T1::pod_type in_T;
+  
+  const in_T y = std::real(expr.aux_out_eT);
+  
+  const bool status = op_powmat_cx::apply_direct(out, expr.m, y);
+  
+  if(status == false)
+    {
+    out.soft_reset();
+    arma_stop_runtime_error("powmat(): transformation failed");
+    }
+  }
+
+
+
+template<typename T1>
+inline
+bool
+op_powmat_cx::apply_direct(Mat< std::complex<typename T1::pod_type> >& out, const Base<typename T1::elem_type,T1>& X, const typename T1::pod_type y)
+  {
+  arma_extra_debug_sigprint();
+  
+  typedef typename T1::elem_type in_eT;
+  typedef typename T1::pod_type  in_T;
+  typedef std::complex<in_T>     out_eT;
+  
+  if( y == in_T(int(y)) )
+    {
+    arma_extra_debug_print("op_powmat_cx::apply_direct(): integer exponent detected; redirecting to op_powmat");
+    
+    const uword y_val = (y < int(0)) ? uword(-y) : uword(y);
+    const bool  y_neg = (y < int(0));
+    
+    Mat<in_eT> tmp;
+    
+    const bool status = op_powmat::apply_direct(tmp, X.get_ref(), y_val, y_neg);
+    
+    if(status == false)  { return false; }
+    
+    out = conv_to< Mat<out_eT> >::from(tmp);
+    
+    return true;
+    }
+  
+  const quasi_unwrap<T1> U(X.get_ref());
+  const Mat<in_eT>& A  = U.M;
+  
+  arma_debug_check( (A.is_square() == false), "powmat(): given matrix must be square sized" );
+  
+  const uword N = A.n_rows;
+  
+  if(A.is_diagmat())
+    {
+    arma_extra_debug_print("op_powmat_cx: detected diagonal matrix");
+    
+    podarray<out_eT> tmp(N);  // use temporary array in case we have aliasing
+    
+    for(uword i=0; i<N; ++i)  { tmp[i] = eop_aux::pow( std::complex<in_T>(A.at(i,i)), y) ; }
+    
+    out.zeros(N,N);
+    
+    for(uword i=0; i<N; ++i)  { out.at(i,i) = tmp[i]; }
+    
+    return true;
+    }
+  
+  const bool try_sympd = arma_config::optimise_sym && sym_helper::guess_sympd(A);
+  
+  if(try_sympd)
+    {
+    arma_extra_debug_print("op_powmat_cx: attempting sympd optimisation");
+    
+    Col<in_T>  eigval;
+    Mat<in_eT> eigvec;
+    
+    const bool eig_status = eig_sym(eigval, eigvec, A);
+    
+    if(eig_status)
+      {
+      eigval = pow(eigval, y);
+      
+      const Mat<in_eT> tmp = diagmat(eigval) * eigvec.t();
+      
+      out = conv_to< Mat<out_eT> >::from(eigvec * tmp);
+      
+      return true;
+      }
+    
+    arma_extra_debug_print("op_powmat_cx: sympd optimisation failed");
+    
+    // fallthrough if optimisation failed
+    }
+  
+  bool powmat_status = false;
+  
+  Col<out_eT> eigval;
+  Mat<out_eT> eigvec;
+  
+  const bool eig_status = eig_gen(eigval, eigvec, A);
+  
+  if(eig_status)
+    {
+    eigval = pow(eigval, y);
+    
+    Mat<out_eT> eigvec_t = trans(eigvec);
+    Mat<out_eT> tmp      = diagmat(conj(eigval)) * eigvec_t;
+    
+    const bool solve_status = auxlib::solve_square_fast(out, eigvec_t, tmp);
+    
+    if(solve_status)  { out = trans(out); powmat_status = true; }
+    }
+  
+  return powmat_status;
+  }
+
+
+
+//! @}