// This file is generated by WOK (CPPExt).
// Please do not edit this file; modify original file instead.
// The copyright and license terms as defined for the original file apply to 
// this header file considered to be the "object code" form of the original source.

#ifndef _math_Crout_HeaderFile
#define _math_Crout_HeaderFile

#include <Standard.hxx>
#include <Standard_DefineAlloc.hxx>
#include <Standard_Macro.hxx>

#include <math_Matrix.hxx>
#include <Standard_Boolean.hxx>
#include <Standard_Real.hxx>
#include <math_Vector.hxx>
#include <Standard_OStream.hxx>
class StdFail_NotDone;
class math_NotSquare;
class Standard_DimensionError;
class math_Matrix;


//! This class implements the Crout algorithm used to solve a
//! system A*X = B where A is a symmetric matrix. It can be used to
//! invert a symmetric matrix.
//! This algorithm is similar to Gauss but is faster than Gauss.
//! Only the inferior triangle of A and the diagonal can be given.
class math_Crout 
{
public:

  DEFINE_STANDARD_ALLOC

  
  //! Given an input matrix A, this algorithm inverts A by the
  //! Crout algorithm. The user can give only the inferior
  //! triangle for the implementation.
  //! A can be decomposed like this:
  //! A = L * D * T(L) where L is triangular inferior and D is
  //! diagonal.
  //! If one element of A is less than MinPivot, A is
  //! considered as singular.
  //! Exception NotSquare is raised if A is not a square matrix.
  Standard_EXPORT math_Crout(const math_Matrix& A, const Standard_Real MinPivot = 1.0e-20);
  
  //! Returns True if all has been correctly done.
      Standard_Boolean IsDone()  const;
  
  //! Given an input vector <B>, this routine returns the
  //! solution of the set of linear equations A . X = B.
  //! Exception NotDone is raised if the decomposition was not
  //! done successfully.
  //! Exception DimensionError is raised if the range of B is
  //! not equal to the rowrange of A.
  Standard_EXPORT   void Solve (const math_Vector& B, math_Vector& X)  const;
  
  //! returns the inverse matrix of A. Only the inferior
  //! triangle is returned.
  //! Exception NotDone is raised if NotDone.
     const  math_Matrix& Inverse()  const;
  
  //! returns in Inv the inverse matrix of A. Only the inferior
  //! triangle is returned.
  //! Exception NotDone is raised if NotDone.
      void Invert (math_Matrix& Inv)  const;
  
  //! Returns the value of the determinant of the previously LU
  //! decomposed matrix A. Zero is returned if the matrix A is considered as singular.
  //! Exceptions
  //! StdFail_NotDone if the algorithm fails (and IsDone returns false).
      Standard_Real Determinant()  const;
  
  //! Prints on the stream o information on the current state
  //! of the object.
  Standard_EXPORT   void Dump (Standard_OStream& o)  const;




protected:





private:



  math_Matrix InvA;
  Standard_Boolean Done;
  Standard_Real Det;


};


#include <math_Crout.lxx>





#endif // _math_Crout_HeaderFile
