1 // Created on: 1991-03-14
2 // Created by: Laurent PAINNOT
3 // Copyright (c) 1991-1999 Matra Datavision
4 // Copyright (c) 1999-2014 OPEN CASCADE SAS
6 // This file is part of Open CASCADE Technology software library.
8 // This library is free software; you can redistribute it and/or modify it under
9 // the terms of the GNU Lesser General Public License version 2.1 as published
10 // by the Free Software Foundation, with special exception defined in the file
11 // OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
12 // distribution for complete text of the license and disclaimer of any warranty.
14 // Alternatively, this file may be used under the terms of Open CASCADE
15 // commercial license or contractual agreement.
17 #ifndef _math_FunctionRoot_HeaderFile
18 #define _math_FunctionRoot_HeaderFile
20 #include <Standard.hxx>
21 #include <Standard_DefineAlloc.hxx>
22 #include <Standard_Handle.hxx>
24 #include <Standard_Boolean.hxx>
25 #include <Standard_Real.hxx>
26 #include <Standard_Integer.hxx>
27 #include <Standard_OStream.hxx>
28 class StdFail_NotDone;
29 class math_FunctionWithDerivative;
33 //! This class implements the computation of a root of a function of
34 //! a single variable which is near an initial guess using a minimization
35 //! algorithm.Knowledge of the derivative is required. The
36 //! algorithm used is the same as in
37 class math_FunctionRoot
45 //! The Newton-Raphson method is done to find the root of the function F
46 //! from the initial guess Guess.The tolerance required on
47 //! the root is given by Tolerance. Iterations are stopped if
48 //! the expected solution does not stay in the range A..B.
49 //! The solution is found when abs(Xi - Xi-1) <= Tolerance;
50 //! The maximum number of iterations allowed is given by NbIterations.
51 Standard_EXPORT math_FunctionRoot(math_FunctionWithDerivative& F, const Standard_Real Guess, const Standard_Real Tolerance, const Standard_Integer NbIterations = 100);
54 //! The Newton-Raphson method is done to find the root of the function F
55 //! from the initial guess Guess.
56 //! The tolerance required on the root is given by Tolerance.
57 //! Iterations are stopped if the expected solution does not stay in the
59 //! The solution is found when abs(Xi - Xi-1) <= Tolerance;
60 //! The maximum number of iterations allowed is given by NbIterations.
61 Standard_EXPORT math_FunctionRoot(math_FunctionWithDerivative& F, const Standard_Real Guess, const Standard_Real Tolerance, const Standard_Real A, const Standard_Real B, const Standard_Integer NbIterations = 100);
63 //! Returns true if the computations are successful, otherwise returns false.
64 Standard_Boolean IsDone() const;
66 //! returns the value of the root.
67 //! Exception NotDone is raised if the root was not found.
68 Standard_Real Root() const;
70 //! returns the value of the derivative at the root.
71 //! Exception NotDone is raised if the root was not found.
72 Standard_Real Derivative() const;
74 //! returns the value of the function at the root.
75 //! Exception NotDone is raised if the root was not found.
76 Standard_Real Value() const;
78 //! returns the number of iterations really done on the
79 //! computation of the Root.
80 //! Exception NotDone is raised if the root was not found.
81 Standard_Integer NbIterations() const;
83 //! Prints on the stream o information on the current state
85 //! Is used to redefine the operator <<.
86 Standard_EXPORT void Dump (Standard_OStream& o) const;
101 Standard_Boolean Done;
102 Standard_Real TheRoot;
103 Standard_Real TheError;
104 Standard_Real TheDerivative;
105 Standard_Integer NbIter;
111 #include <math_FunctionRoot.lxx>
117 #endif // _math_FunctionRoot_HeaderFile