-- File:	Law_Function.cdl
-- Created:	Fri Dec 24 10:43:17 1993
-- Author:	Jacques GOUSSARD
--		<jag@topsn2>
---Copyright:	 Matra Datavision 1993


deferred class Function from Law

	---Purpose: Root class for evolution laws.

inherits TShared from MMgt


uses  Array1OfReal    from TColStd,
      Shape           from GeomAbs
      
raises OutOfRange from Standard


is
    Continuity(me) returns Shape from GeomAbs
    is deferred;
    
    NbIntervals(me; S : Shape from GeomAbs) returns Integer
	---Purpose: Returns  the number  of  intervals for  continuity
	--          <S>. May be one if Continuity(me) >= <S>
    is deferred;
    
    Intervals(me; T : in out Array1OfReal from TColStd; 
    	          S : Shape from GeomAbs)
	---Purpose: Stores in <T> the  parameters bounding the intervals
	--          of continuity <S>.
	--          
	--          The array must provide  enough room to  accomodate
	--          for the parameters. i.e. T.Length() > NbIntervals()
    raises
    	OutOfRange from Standard 
    is deferred;
    
    Value(me: mutable; X: Real from Standard)
    
	---Purpose: Returns the value of the function at the point of parameter X.

    	returns Real from Standard
	is deferred;


    D1(me: mutable; X: Real from Standard; F,D: out Real from Standard)
    
	---Purpose: Returns the value F and the first derivative D of the
    	-- function at the point of parameter X.

	is deferred;
	
    
    D2(me: mutable; X: Real from Standard; F,D, D2: out Real from Standard)
    
	---Purpose: Returns the value, first and seconde derivatives 
	--          at parameter X.

	is deferred;

    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 deferred;    

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

end Function;