annotate armadillo-2.4.4/include/armadillo_bits/fn_det.hpp @ 18:8d046a9d36aa slimline

Back out rev 13:ac07c60aa798. Like an idiot, I committed a whole pile of unrelated changes in the guise of a single typo fix. Will re-commit in stages
author Chris Cannam
date Thu, 10 May 2012 10:45:44 +0100
parents 8b6102e2a9b0
children
rev   line source
max@0 1 // Copyright (C) 2008-2011 NICTA (www.nicta.com.au)
max@0 2 // Copyright (C) 2008-2011 Conrad Sanderson
max@0 3 //
max@0 4 // This file is part of the Armadillo C++ library.
max@0 5 // It is provided without any warranty of fitness
max@0 6 // for any purpose. You can redistribute this file
max@0 7 // and/or modify it under the terms of the GNU
max@0 8 // Lesser General Public License (LGPL) as published
max@0 9 // by the Free Software Foundation, either version 3
max@0 10 // of the License or (at your option) any later version.
max@0 11 // (see http://www.opensource.org/licenses for more info)
max@0 12
max@0 13
max@0 14 //! \addtogroup fn_det
max@0 15 //! @{
max@0 16
max@0 17
max@0 18
max@0 19 //! determinant of mat
max@0 20 template<typename T1>
max@0 21 inline
max@0 22 arma_warn_unused
max@0 23 typename T1::elem_type
max@0 24 det
max@0 25 (
max@0 26 const Base<typename T1::elem_type,T1>& X,
max@0 27 const bool slow = false,
max@0 28 const typename arma_blas_type_only<typename T1::elem_type>::result* junk = 0
max@0 29 )
max@0 30 {
max@0 31 arma_extra_debug_sigprint();
max@0 32
max@0 33 arma_ignore(junk);
max@0 34
max@0 35 return auxlib::det(X, slow);
max@0 36 }
max@0 37
max@0 38
max@0 39
max@0 40 //! determinant of diagmat
max@0 41 template<typename T1>
max@0 42 inline
max@0 43 arma_warn_unused
max@0 44 typename T1::elem_type
max@0 45 det
max@0 46 (
max@0 47 const Op<T1, op_diagmat>& X,
max@0 48 const bool slow = false
max@0 49 )
max@0 50 {
max@0 51 arma_extra_debug_sigprint();
max@0 52 arma_ignore(slow);
max@0 53
max@0 54 typedef typename T1::elem_type eT;
max@0 55
max@0 56 const diagmat_proxy<T1> A(X.m);
max@0 57
max@0 58 const uword A_n_elem = A.n_elem;
max@0 59
max@0 60 eT val = eT(1);
max@0 61
max@0 62 for(uword i=0; i<A_n_elem; ++i)
max@0 63 {
max@0 64 val *= A[i];
max@0 65 }
max@0 66
max@0 67 return val;
max@0 68 }
max@0 69
max@0 70
max@0 71
max@0 72 //! determinant of inv(A), without doing the inverse operation
max@0 73 template<typename T1>
max@0 74 inline
max@0 75 arma_warn_unused
max@0 76 typename T1::elem_type
max@0 77 det
max@0 78 (
max@0 79 const Op<T1,op_inv>& in,
max@0 80 const bool slow = false,
max@0 81 const typename arma_blas_type_only<typename T1::elem_type>::result* junk = 0
max@0 82 )
max@0 83 {
max@0 84 arma_extra_debug_sigprint();
max@0 85 arma_ignore(junk);
max@0 86
max@0 87 typedef typename T1::elem_type eT;
max@0 88
max@0 89 eT tmp = det(in.m, slow);
max@0 90 arma_warn( (tmp == eT(0)), "det(): warning: denominator is zero" );
max@0 91
max@0 92 return eT(1) / tmp;
max@0 93 }
max@0 94
max@0 95
max@0 96
max@0 97 //! determinant of trans(A)
max@0 98 template<typename T1>
max@0 99 inline
max@0 100 arma_warn_unused
max@0 101 typename T1::elem_type
max@0 102 det
max@0 103 (
max@0 104 const Op<T1,op_htrans>& in,
max@0 105 const bool slow = false,
max@0 106 const typename arma_blas_type_only<typename T1::elem_type>::result* junk1 = 0,
max@0 107 const typename arma_not_cx<typename T1::elem_type>::result* junk2 = 0
max@0 108 )
max@0 109 {
max@0 110 arma_extra_debug_sigprint();
max@0 111 arma_ignore(junk1);
max@0 112 arma_ignore(junk2);
max@0 113
max@0 114 typedef typename T1::elem_type eT;
max@0 115
max@0 116 const unwrap<T1> tmp(in.m);
max@0 117 const Mat<eT>& X = tmp.M;
max@0 118
max@0 119 return det(X, slow);
max@0 120 }
max@0 121
max@0 122
max@0 123
max@0 124 //! @}