OCCT

// Created on: 1998-11-06
// Created by: Igor FEOKTISTOV
// Copyright (c) 1998-1999 Matra Datavision
// Copyright (c) 1999-2014 OPEN CASCADE SAS
//
// This file is part of Open CASCADE Technology software library.
//
// This library is free software; you can redistribute it and/or modify it under
// the terms of the GNU Lesser General Public License version 2.1 as published
// by the Free Software Foundation, with special exception defined in the file
// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
// distribution for complete text of the license and disclaimer of any warranty.
//
// Alternatively, this file may be used under the terms of Open CASCADE
// commercial license or contractual agreement.

#include <FEmTool_LinearFlexion.hxx>
#include "FEmTool_LinearCriterion.pxx"
#include <math_Matrix.hxx>
#include <math_Vector.hxx>
#include <PLib.hxx>
#include <Standard_DomainError.hxx>
#include <Standard_NotImplemented.hxx>
#include <Standard_Type.hxx>
#include <Standard_Integer.hxx>
#include <NCollection_Array2.hxx>
#include <NCollection_HArray2.hxx>

IMPLEMENT_STANDARD_RTTIEXT(FEmTool_LinearFlexion, FEmTool_ElementaryCriterion)

//=================================================================================================

FEmTool_LinearFlexion::FEmTool_LinearFlexion(const int           WorkDegree,
                                             const GeomAbs_Shape ConstraintOrder)
    : RefMatrix(0, WorkDegree, 0, WorkDegree)
{
  myOrder = PLib::NivConstr(ConstraintOrder);
  FEmTool_LinearCriterion::initializeReferenceMatrix<2>(WorkDegree, ConstraintOrder, RefMatrix);
}

//=================================================================================================

occ::handle<NCollection_HArray2<int>> FEmTool_LinearFlexion::DependenceTable() const
{
  if (myCoeff.IsNull())
  {
    throw Standard_DomainError("FEmTool_LinearFlexion::DependenceTable");
  }

  occ::handle<NCollection_HArray2<int>> DepTab = new NCollection_HArray2<int>(myCoeff->LowerCol(),
                                                                              myCoeff->UpperCol(),
                                                                              myCoeff->LowerCol(),
                                                                              myCoeff->UpperCol(),
                                                                              0);
  int                                   i;
  for (i = myCoeff->LowerCol(); i <= myCoeff->UpperCol(); i++)
  {
    DepTab->SetValue(i, i, 1);
  }

  return DepTab;
}

//=================================================================================================

double FEmTool_LinearFlexion::Value()
{
  int deg = std::min(myCoeff->ColLength() - 1, RefMatrix.UpperRow()), i, j,
      j0 = myCoeff->LowerRow(), degH = std::min(2 * myOrder + 1, deg), NbDim = myCoeff->RowLength(),
      dim;

  NCollection_Array2<double> NewCoeff(1, NbDim, 0, deg);

  double coeff = (myLast - myFirst) / 2., cteh3 = 2. / std::pow(coeff, 3), mfact, Jline;

  int k1;

  double J = 0.;

  for (i = 0; i <= degH; i++)
  {
    k1    = (i <= myOrder) ? i : i - myOrder - 1;
    mfact = std::pow(coeff, k1);
    for (dim = 1; dim <= NbDim; dim++)
    {
      NewCoeff(dim, i) = myCoeff->Value(j0 + i, dim) * mfact;
    }
  }

  for (i = degH + 1; i <= deg; i++)
  {
    for (dim = 1; dim <= NbDim; dim++)
    {
      NewCoeff(dim, i) = myCoeff->Value(j0 + i, dim);
    }
  }

  for (dim = 1; dim <= NbDim; dim++)
  {
    for (i = 0; i <= deg; i++)
    {
      Jline = 0.5 * RefMatrix(i, i) * NewCoeff(dim, i);
      for (j = 0; j < i; j++)
      {
        Jline += RefMatrix(i, j) * NewCoeff(dim, j);
      }
      J += Jline * NewCoeff(dim, i);
    }
  }

  if (J < 0.)
  {
    J = 0.;
  }
  return cteh3 * J;
}

//=================================================================================================

void FEmTool_LinearFlexion::Hessian(const int Dimension1, const int Dimension2, math_Matrix& H)
{

  occ::handle<NCollection_HArray2<int>> DepTab = DependenceTable();

  if (Dimension1 < DepTab->LowerRow() || Dimension1 > DepTab->UpperRow()
      || Dimension2 < DepTab->LowerCol() || Dimension2 > DepTab->UpperCol())
  {
    throw Standard_OutOfRange("FEmTool_LinearJerk::Hessian");
  }

  if (DepTab->Value(Dimension1, Dimension2) == 0)
  {
    throw Standard_DomainError("FEmTool_LinearJerk::Hessian");
  }

  int deg  = std::min(RefMatrix.UpperRow(), H.RowNumber() - 1),
      degH = std::min(2 * myOrder + 1, deg);

  double coeff = (myLast - myFirst) / 2., cteh3 = 2. / std::pow(coeff, 3), mfact;
  int    k1, k2, i, j;

  H.Init(0.);

  for (i = 0; i <= degH; i++)
  {
    k1    = (i <= myOrder) ? i : i - myOrder - 1;
    mfact = std::pow(coeff, k1) * cteh3;
    // Hermite*Hermite part of matrix
    for (j = i; j <= degH; j++)
    {
      k2      = (j <= myOrder) ? j : j - myOrder - 1;
      H(i, j) = mfact * std::pow(coeff, k2) * RefMatrix(i, j);
      if (i != j)
      {
        H(j, i) = H(i, j);
      }
    }
    // Hermite*Jacobi part of matrix
    for (j = degH + 1; j <= deg; j++)
    {
      H(i, j) = H(j, i) = mfact * RefMatrix(i, j);
    }
  }

  // Jacoby*Jacobi part of matrix
  for (i = degH + 1; i <= deg; i++)
  {
    for (j = i; j <= deg; j++)
    {
      H(i, j) = cteh3 * RefMatrix(i, j);
      if (i != j)
      {
        H(j, i) = H(i, j);
      }
    }
  }
}

//=================================================================================================

void FEmTool_LinearFlexion::Gradient(const int Dimension, math_Vector& G)
{
  if (Dimension < myCoeff->LowerCol() || Dimension > myCoeff->UpperCol())
  {
    throw Standard_OutOfRange("FEmTool_LinearFlexion::Gradient");
  }

  int deg = std::min(G.Length() - 1, myCoeff->ColLength() - 1);

  math_Vector X(0, deg);
  math_Matrix H(0, deg, 0, deg);
  int         i, i1 = myCoeff->LowerRow();
  for (i = 0; i <= deg; i++)
  {
    X(i) = myCoeff->Value(i1 + i, Dimension);
  }

  Hessian(Dimension, Dimension, H);

  G.Multiply(H, X);
}