-- File:	FunctionDerivative.cdl
-- Created:	Mon Jan 14 10:53:24 1991
-- Author:	Arnaud BOUZY
--		<adn@topsn3>
---Copyright:	 Matra Datavision 1991, 1992

class FunctionDerivative from Expr

inherits GeneralFunction from Expr

uses NamedUnknown from Expr, 
    GeneralExpression from Expr,
    Array1OfNamedUnknown from Expr,
    Array1OfReal from TColStd,
    AsciiString from TCollection

raises OutOfRange from Standard,
    DimensionMismatch from Standard,
    NumericError from Standard,
    NotEvaluable from Expr

is

    Create(func : GeneralFunction; withX : NamedUnknown; deg : Integer)
    ---Purpose: Creates a FunctionDerivative of degree <deg> relative 
    --          to the <withX> variable.
    --          Raises OutOfRange if <deg> lower or equal to zero.
    ---Level : Advanced
    returns mutable FunctionDerivative
    raises OutOfRange;

    NbOfVariables(me)
    ---Purpose: Returns the number of variables of <me>.
    returns Integer;

    Variable(me; index : Integer)
    ---Purpose: Returns the variable denoted by <index> in <me>.
    --          Raises OutOfRange if <index> greater than 
    --          NbOfVariables of <me>. 
    returns NamedUnknown
    raises OutOfRange;
    
    Evaluate(me; vars : Array1OfNamedUnknown; 
    	    	values : Array1OfReal)
    ---Purpose: Computes the value of <me> with the given variables.
    --          Raises DimensionMismatch if Length(vars) is different from 
    --          Length(values).
    returns Real
    raises DimensionMismatch, NumericError,NotEvaluable;

    Copy(me)
    ---Purpose: Returns a copy of <me> with the same form.
    returns mutable like me;

    Derivative(me; var : NamedUnknown)
    ---Purpose: Returns Derivative of <me> for variable <var>.
    returns GeneralFunction;
    
    Derivative(me; var : NamedUnknown; deg : Integer)
    ---Purpose: Returns Derivative of <me> for variable <var> with 
    --          degree <deg>.
    returns GeneralFunction;
    
    IsIdentical(me; func : GeneralFunction)
    ---Purpose: Tests if <me> and <func> are similar functions (same 
    --          name and same used expression).
    returns Boolean;

    IsLinearOnVariable(me; index : Integer)
    ---Purpose: Tests if <me> is linear on variable on range <index>
    returns Boolean;
    
    Function(me)
    ---Purpose: Returns the function of which <me> is the derivative.
    ---Level : Internal
    returns GeneralFunction
    is static;
    
    Degree(me)
    ---Purpose: Returns the degree of derivation of <me>.
    ---Level : Internal
    returns Integer
    is static;
    
    DerivVariable(me)
    ---Purpose: Returns the derivation variable of <me>.
    ---Level : Internal
    returns NamedUnknown
    is static;
    
    GetStringName(me)
    returns AsciiString;
    
    Expression(me)
    returns GeneralExpression
    ---Level : Internal
    is static;
    
    UpdateExpression(me: mutable);
    ---Level : Internal

fields

    myFunction : GeneralFunction;
    myExp : GeneralExpression;
    myDerivate : NamedUnknown;
    myDegree : Integer;

friends

    class NamedFunction from Expr
    
end FunctionDerivative;