comparison armadillo-2.4.4/include/armadillo_bits/fn_det.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 fn_det
+//! @{
+
+
+
+//! determinant of mat
+template<typename T1>
+inline
+arma_warn_unused
+typename T1::elem_type
+det
+  (
+  const Base<typename T1::elem_type,T1>& X,
+  const bool slow = false,
+  const typename arma_blas_type_only<typename T1::elem_type>::result* junk = 0
+  )
+  {
+  arma_extra_debug_sigprint();
+  
+  arma_ignore(junk);
+  
+  return auxlib::det(X, slow);
+  }
+
+
+
+//! determinant of diagmat
+template<typename T1>
+inline
+arma_warn_unused
+typename T1::elem_type
+det
+  (
+  const Op<T1, op_diagmat>& X,
+  const bool slow = false
+  )
+  {
+  arma_extra_debug_sigprint();
+  arma_ignore(slow);
+  
+  typedef typename T1::elem_type eT;
+  
+  const diagmat_proxy<T1> A(X.m);
+  
+  const uword A_n_elem = A.n_elem;
+  
+  eT val = eT(1);
+  
+  for(uword i=0; i<A_n_elem; ++i)
+    {
+    val *= A[i];
+    }
+  
+  return val;
+  }
+
+
+
+//! determinant of inv(A), without doing the inverse operation
+template<typename T1>
+inline
+arma_warn_unused
+typename T1::elem_type
+det
+  (
+  const Op<T1,op_inv>& in,
+  const bool slow = false,
+  const typename arma_blas_type_only<typename T1::elem_type>::result* junk = 0
+  )
+  {
+  arma_extra_debug_sigprint();
+  arma_ignore(junk);
+  
+  typedef typename T1::elem_type eT;
+  
+  eT tmp = det(in.m, slow);
+  arma_warn( (tmp == eT(0)), "det(): warning: denominator is zero" );
+  
+  return eT(1) / tmp;
+  }
+
+
+
+//! determinant of trans(A)
+template<typename T1>
+inline
+arma_warn_unused
+typename T1::elem_type
+det
+  (
+  const Op<T1,op_htrans>& in,
+  const bool slow = false,
+  const typename arma_blas_type_only<typename T1::elem_type>::result* junk1 = 0,
+  const typename         arma_not_cx<typename T1::elem_type>::result* junk2 = 0
+  )
+  {
+  arma_extra_debug_sigprint();
+  arma_ignore(junk1);
+  arma_ignore(junk2);
+  
+  typedef typename T1::elem_type eT;
+  
+  const unwrap<T1>   tmp(in.m);
+  const Mat<eT>& X = tmp.M;
+  
+  return det(X, slow);
+  }
+
+
+
+//! @}