lapack_support.h

// ---------------------------------------------------------------------
//
// Copyright (C) 2005 - 2018 by the deal.II authors
//
// This file is part of the deal.II library.
//
// The deal.II library is free software; you can use it, redistribute
// it, and/or modify it under the terms of the GNU Lesser General
// Public License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
// The full text of the license can be found in the file LICENSE.md at
// the top level directory of deal.II.
//
// ---------------------------------------------------------------------

#ifndef dealii_lapack_support_h
#define dealii_lapack_support_h


#include <deal.II/base/config.h>

#include <deal.II/base/exceptions.h>

DEAL_II_NAMESPACE_OPEN

namespace types
{
#ifdef LAPACK_WITH_64BIT_BLAS_INDICES

  using blas_int = long long;
#else

  using blas_int = int;
#endif
} // namespace types

namespace LAPACKSupport
{
  enum State
  {
    matrix,
    inverse_matrix,
    lu,
    cholesky,
    eigenvalues,
    svd,
    inverse_svd,
    unusable = 0x8000
  };

  inline const char *
  state_name(State s)
  {
    switch (s)
      {
        case matrix:
          return "matrix";
        case inverse_matrix:
          return "inverse matrix";
        case lu:
          return "lu decomposition";
        case cholesky:
          return "cholesky decomposition";
        case eigenvalues:
          return "eigenvalues";
        case svd:
          return "svd";
        case inverse_svd:
          return "inverse_svd";
        case unusable:
          return "unusable";
        default:
          return "unknown";
      }
  }

  enum Property
  {
    general = 0,
    symmetric = 1,
    upper_triangular = 2,
    lower_triangular = 4,
    diagonal = 6,
    hessenberg = 8
  };

  inline const char *
  property_name(const Property s)
  {
    switch (s)
      {
        case general:
          return "general";
        case symmetric:
          return "symmetric";
        case upper_triangular:
          return "upper triangular";
        case lower_triangular:
          return "lower triangular";
        case diagonal:
          return "diagonal";
        case hessenberg:
          return "Hessenberg";
      }

    Assert(false, ExcNotImplemented());
    return "invalid";
  }

  static const char A = 'A';
  static const char N = 'N';
  static const char T = 'T';
  static const char U = 'U';
  static const char L = 'L';
  static const char V = 'V';
  static const types::blas_int zero = 0;
  static const types::blas_int one = 1;

  DeclException2(ExcErrorCode,
                 std::string,
                 types::blas_int,
                 << "The function " << arg1 << " returned with an error code "
                 << arg2);

  DeclException1(
    ExcState,
    State,
    << "The function cannot be called while the matrix is in state "
    << state_name(arg1));

  DeclException1(ExcProperty,
                 Property,
                 << "The function cannot be called with a "
                 << property_name(arg1) << " matrix.");

  DeclException1(
    ExcMissing,
    std::string,
    << "When you ran 'cmake' during installation of deal.II, "
    << "no suitable installation of the BLAS or LAPACK library could "
    << "be found. Consequently, the function <" << arg1
    << "> can not be called. Refer to the doc/readme.html "
    << "file for information on how to ensure that deal.II "
    << "picks up an existing BLAS and LAPACK installation at "
    << "configuration time.");
} // namespace LAPACKSupport


DEAL_II_NAMESPACE_CLOSE

#endif