-- File:	Law_Linear.cdl
-- Created:	Thu Jan 12 10:36:44 1995
-- Author:	Laurent BOURESCHE
--		<lbo@phylox>
---Copyright:	 Matra Datavision 1995



class Linear from Law inherits Function from Law

	---Purpose: Describes an linear evolution law. 
uses
    Array1OfReal    from TColStd,
    Shape           from GeomAbs
      
raises OutOfRange from Standard

is

    Create
    
    	returns mutable Linear from Law;
    	---Purpose: Constructs an empty linear evolution law.

    Set(me: mutable; Pdeb,Valdeb,Pfin,Valfin: Real from Standard)
    	---Purpose:
    	-- Defines this linear evolution law by assigning both:
    	-- -   the bounds Pdeb and Pfin of the parameter, and
    	-- -   the values Valdeb and Valfin of the function at these
    	--   two parametric bounds.   
    	is static;
    Continuity(me) returns Shape from GeomAbs
    	---Purpose: Returns GeomAbs_CN
    is redefined static;
    
    NbIntervals(me; S : Shape from GeomAbs) returns Integer
	---Purpose: Returns  1
    is redefined static;
    
    Intervals(me; T : in out Array1OfReal from TColStd; 
    	          S : Shape from GeomAbs)
    raises
    	OutOfRange from Standard 
    is redefined static;



    Value(me: mutable; X: Real from Standard)
    
    	returns Real from Standard;
	---Purpose: Returns the value of this function at the point of parameter X.

    D1(me: mutable; X: Real from Standard; F,D: out Real from Standard); 
    	---Purpose:
    	-- Returns the value F and the first derivative D of this
    	-- function at the point of parameter X.    
    D2(me: mutable; X: Real from Standard; 
       F,D, D2: out Real from Standard);
    	---Purpose: Returns the value, first and second derivatives 
    	--          at parameter X.
    
    Trim(me; PFirst, PLast, Tol :Real from Standard) returns Function
    
    	---Purpose:   Returns a  law equivalent of  <me>  between
	--        parameters <First>  and <Last>. <Tol>  is used  to
	--        test for 3d points confusion.
	--        It is usfule to determines the derivatives 
	--        in these values <First> and <Last> if 
        --        the Law is not Cn.          
    	is redefined static;

    Bounds(me: mutable; PFirst,PLast: out Real from Standard);
    	---Purpose: Returns the parametric bounds of the function.    

fields

    valdeb  : Real from Standard;
    valfin  : Real from Standard;
    pdeb    : Real from Standard;
    pfin    : Real from Standard;

end Linear;