// 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 fn_qz
//! @{

//! QZ decomposition for pair of N-by-N general matrices A and B
template <typename T1, typename T2>
inline typename enable_if2<is_supported_blas_type<typename T1::elem_type>::value,
                           bool>::result
qz(Mat<typename T1::elem_type>& AA, Mat<typename T1::elem_type>& BB,
   Mat<typename T1::elem_type>& Q, Mat<typename T1::elem_type>& Z,
   const Base<typename T1::elem_type, T1>& A_expr,
   const Base<typename T1::elem_type, T2>& B_expr, const char* select = "none") {
  arma_debug_sigprint();

  const char sig = (select != nullptr) ? select[0] : char(0);

  arma_conform_check(
      ((sig != 'n') && (sig != 'l') && (sig != 'r') && (sig != 'i') && (sig != 'o')),
      "qz(): unknown select form");

  const bool status = auxlib::qz(AA, BB, Q, Z, A_expr.get_ref(), B_expr.get_ref(), sig);

  if (status == false) {
    AA.soft_reset();
    BB.soft_reset();
    Q.soft_reset();
    Z.soft_reset();
    arma_warn(3, "qz(): decomposition failed");
  }

  return status;
}

//! @}
