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armadillo-code/include/armadillo_bits/fn_eig_sym.hpp
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// 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 fn_eig_sym
//! @{
//! Eigenvalues of real/complex symmetric/hermitian matrix X
template<typename T1>
inline
typename enable_if2< is_supported_blas_type<typename T1::elem_type>::value, bool >::result
eig_sym
(
Col<typename T1::pod_type>& eigval,
const Base<typename T1::elem_type,T1>& X
)
{
arma_extra_debug_sigprint();
// unwrap_check not used as T1::elem_type and T1::pod_type may not be the same.
// furthermore, it doesn't matter if X is an alias of eigval, as auxlib::eig_sym() makes a copy of X
const bool status = auxlib::eig_sym(eigval, X);
if(status == false)
{
eigval.soft_reset();
arma_debug_warn_level(3, "eig_sym(): decomposition failed");
}
return status;
}
//! Eigenvalues of real/complex symmetric/hermitian matrix X
template<typename T1>
arma_warn_unused
inline
typename enable_if2< is_supported_blas_type<typename T1::elem_type>::value, Col<typename T1::pod_type> >::result
eig_sym
(
const Base<typename T1::elem_type,T1>& X
)
{
arma_extra_debug_sigprint();
Col<typename T1::pod_type> out;
const bool status = auxlib::eig_sym(out, X);
if(status == false)
{
out.soft_reset();
arma_stop_runtime_error("eig_sym(): decomposition failed");
}
return out;
}
//! internal helper function
template<typename eT>
inline
bool
eig_sym_helper
(
Col<typename get_pod_type<eT>::result>& eigval,
Mat<eT>& eigvec,
const Mat<eT>& X,
const char method_sig,
const char* caller_sig
)
{
arma_extra_debug_sigprint();
// if(auxlib::rudimentary_sym_check(X) == false)
// {
// if(is_cx<eT>::no ) { arma_debug_warn_level(1, caller_sig, ": given matrix is not symmetric"); }
// if(is_cx<eT>::yes) { arma_debug_warn_level(1, caller_sig, ": given matrix is not hermitian"); }
// return false;
// }
if((arma_config::debug) && (auxlib::rudimentary_sym_check(X) == false))
{
if(is_cx<eT>::no ) { arma_debug_warn_level(1, caller_sig, ": given matrix is not symmetric"); }
if(is_cx<eT>::yes) { arma_debug_warn_level(1, caller_sig, ": given matrix is not hermitian"); }
}
bool status = false;
if(method_sig == 'd') { status = auxlib::eig_sym_dc(eigval, eigvec, X); }
if(status == false) { status = auxlib::eig_sym(eigval, eigvec, X); }
return status;
}
//! Eigenvalues and eigenvectors of real/complex symmetric/hermitian matrix X
template<typename T1>
inline
typename enable_if2< is_supported_blas_type<typename T1::elem_type>::value, bool >::result
eig_sym
(
Col<typename T1::pod_type>& eigval,
Mat<typename T1::elem_type>& eigvec,
const Base<typename T1::elem_type,T1>& expr,
const char* method = "dc"
)
{
arma_extra_debug_sigprint();
typedef typename T1::elem_type eT;
const char sig = (method != nullptr) ? method[0] : char(0);
arma_debug_check( ((sig != 's') && (sig != 'd')), "eig_sym(): unknown method specified" );
arma_debug_check( void_ptr(&eigval) == void_ptr(&eigvec), "eig_sym(): parameter 'eigval' is an alias of parameter 'eigvec'" );
const quasi_unwrap<T1> U(expr.get_ref());
const bool is_alias = U.is_alias(eigvec);
Mat<eT> eigvec_tmp;
Mat<eT>& eigvec_out = (is_alias == false) ? eigvec : eigvec_tmp;
const bool status = eig_sym_helper(eigval, eigvec_out, U.M, sig, "eig_sym()");
if(status == false)
{
eigval.soft_reset();
eigvec.soft_reset();
arma_debug_warn_level(3, "eig_sym(): decomposition failed");
}
else
{
if(is_alias) { eigvec.steal_mem(eigvec_tmp); }
}
return status;
}
//! @}