-- File:	FairCurve_Newton.cdl
-- Created:	Fri Oct 11 10:01:47 1996
-- Author:	Philippe MANGIN
--		<pmn@sgi29>
---Copyright:	 Matra Datavision 1996


private class Newton from FairCurve inherits NewtonMinimum from  math

	---Purpose: Algorithme of Optimization used to make "FairCurve"

uses 
    Vector from math, 
    MultipleVarFunctionWithHessian from math

is
    Create(F: in out MultipleVarFunctionWithHessian;
    	   StartingPoint: Vector;
	   SpatialTolerance :  Real = 1.0e-7;	   
           CriteriumTolerance: Real = 1.0e-2;
	   NbIterations: Integer=40; 
           Convexity: Real=1.0e-6; 
	   WithSingularity  :  Boolean = Standard_True)
    ---Purpose: -- Given the  starting   point  StartingPoint,
    --            The tolerance  required on  the  solution is given  by
    --            Tolerance.  
    --             Iteration are  stopped if  
    --             (!WithSingularity)  and H(F(Xi)) is not definite
    --             positive  (if the smaller eigenvalue of H < Convexity)
    --             or IsConverged() returns True for 2 successives Iterations.
    --  Warning: Obsolete Constructor (because IsConverged can not be redefined
    --           with this. )
    returns  Newton;

    Create(F: in out MultipleVarFunctionWithHessian;
    	   SpatialTolerance :  Real = 1.0e-7;
           Tolerance: Real=1.0e-7;
	   NbIterations: Integer=40; 
           Convexity: Real=1.0e-6; 
           WithSingularity  :  Boolean = Standard_True)
    ---Purpose:
    --            The tolerance  required on  the  solution is given  by
    --            Tolerance.  
    --             Iteration are  stopped if  
    --             (!WithSingularity)  and H(F(Xi)) is not definite
    --             positive  (if the smaller eigenvalue of H < Convexity)
    --            or IsConverged() returns True for 2 successives Iterations.
    --  Warning: This constructor do not computation 
    returns  Newton;   
	   
    IsConverged(me)
    	---Purpose:  This method is  called    at the end  of   each
    	--          iteration to  check the convergence :
    	--          || Xi+1 - Xi || < SpatialTolerance/100 Or
    	--          || Xi+1 - Xi || < SpatialTolerance and
    	--          |F(Xi+1) - F(Xi)| < CriteriumTolerance * |F(xi)|
    	--          It can be redefined in a sub-class to implement a specific test.
    
    returns Boolean
    is redefined;    

fields
    mySpTol : Real;
end Newton;