-- File:       BracketMinimum.cdl
-- Created:    Tue May 14 14:55:21 1991
-- Author:     Laurent PAINNOT
--             <lpa@topsn3>
---Copyright:   Matra Datavision 1991, 1992



class BracketMinimum from math
     	---Purpose:Given two distinct initial points, BracketMinimum
    	-- implements the computation of three points (a, b, c) which
    	-- bracket the minimum of the function and verify A less than
    	-- B, B less than C and F(A) less than F(B), F(B) less than (C).
uses Vector from math, 
     Matrix from math, 
     Function from math,
     OStream from Standard

raises NotDone from StdFail

is


    Create(F: in out Function; A, B: Real)
      	---Purpose:
      	-- Given two initial values this class computes a
      	-- bracketing triplet of abscissae Ax, Bx, Cx 
      	-- (such that Bx is between Ax and Cx, F(Bx) is 
      	-- less than both F(Bx) and F(Cx)) the Brent minimization is done 
      	-- on the function F.
    
    returns BracketMinimum;
    
    Create(F: in out Function; A, B, FA: Real)
      	---Purpose:
      	-- Given two initial values this class computes a
     	-- bracketing triplet of abscissae Ax, Bx, Cx 
      	-- (such that Bx is between Ax and Cx, F(Bx) is 
      	-- less than both F(Bx) and F(Cx)) the Brent minimization is done 
     	-- on the function F.
      	-- This constructor has to be used if F(A) is known.
    
    returns BracketMinimum;


    Create(F: in out Function; A, B, FA, FB: Real)
      	---Purpose:
      	-- Given two initial values this class computes a
      	-- bracketing triplet of abscissae Ax, Bx, Cx 
      	-- (such that Bx is between Ax and Cx, F(Bx) is 
      	-- less than both F(Bx) and F(Cx)) the Brent minimization is done 
      	-- on the function F.
      	-- This constructor has to be used if F(A) and F(B) are known.
    
    returns BracketMinimum;
    

    Perform(me: in out; F: in out Function; A, B: Real)
    	---Purpose: Is used internally by the constructors.

    is static protected;


    IsDone(me)
    	---Purpose: Returns true if the computations are successful, otherwise returns false.
    	---C++: inline
    returns Boolean
    is static;
    
    
    Values(me; A, B, C: out Real)
    	---Purpose: Returns the bracketed triplet of abscissae.
    	-- Exceptions
    	-- StdFail_NotDone if the algorithm fails (and IsDone returns false).
        
    raises NotDone
    is static;
    


    FunctionValues(me; FA, FB, FC: out Real)
    	---Purpose: returns the bracketed triplet function values.
    	-- Exceptions
    	-- StdFail_NotDone if the algorithm fails (and IsDone returns false).
        
    raises NotDone
    is static;

    
    Dump(me; o: in out OStream)
    	---Purpose: Prints on the stream o information on the current state 
    	--          of the object.
    	--          Is used to redefine the operator <<.

    is static;

    
fields

Done:     Boolean;
Ax:       Real;
Bx:       Real;
Cx:       Real;
FAx:      Real;
FBx:      Real;
FCx:      Real;
myFA:     Boolean;
myFB:     Boolean;

end BracketMinimum;