OCCT

// Created on: 1998-11-10
// 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_ElementsOfRefMatrix.hxx>
#include <PLib_HermitJacobi.hxx>
#include <Standard_ConstructionError.hxx>
#include <NCollection_Array1.hxx>

FEmTool_ElementsOfRefMatrix::FEmTool_ElementsOfRefMatrix(const PLib_HermitJacobi& TheBase,
                                                         const int                DerOrder)
    : myBase(TheBase)
{
  if (DerOrder < 0 || DerOrder > 3)
  {
    throw Standard_ConstructionError("FEmTool_ElementsOfRefMatrix");
  }

  myDerOrder    = DerOrder;
  myNbEquations = (myBase.WorkDegree() + 2) * (myBase.WorkDegree() + 1) / 2;
}

int FEmTool_ElementsOfRefMatrix::NbVariables() const
{
  return 1;
}

int FEmTool_ElementsOfRefMatrix::NbEquations() const
{
  return myNbEquations;
}

bool FEmTool_ElementsOfRefMatrix::Value(const math_Vector& X, math_Vector& F)
{
  if (F.Length() < myNbEquations)
  {
    throw Standard_OutOfRange("FEmTool_ElementsOfRefMatrix::Value");
  }

  double                     u = X(X.Lower());
  NCollection_Array1<double> Basis(0, myBase.WorkDegree()), Aux(0, myBase.WorkDegree());

  switch (myDerOrder)
  {
    case 0:
      myBase.D0(u, Basis);
      break;
    case 1:
      myBase.D1(u, Aux, Basis);
      break;
    case 2:
      myBase.D2(u, Aux, Aux, Basis);
      break;
    case 3:
      myBase.D3(u, Aux, Aux, Aux, Basis);
      break;
  }

  int i, j, ii = 0;
  for (i = 0; i <= myBase.WorkDegree(); i++)
  {
    for (j = i; j <= myBase.WorkDegree(); j++)
    {
      F(F.Lower() + ii) = Basis(i) * Basis(j);
      ii++;
    }
  }

  return true;
}