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-- File: FunctionRoot.cdl
-- Created: Tue 14 11:02:43 1991
-- Author: Laurent PAINNOT
-- <lpa@topsn3>
---Copyright: Matra Datavision 1991, 1992
--
class FunctionRoot from math
---Purpose:
-- This class implements the computation of a root of a function of
-- a single variable which is near an initial guess using a minimization
-- algorithm.Knowledge of the derivative is required. The
-- algorithm used is the same as in
uses Vector from math, Matrix from math,
FunctionWithDerivative from math,
OStream from Standard
raises NotDone from StdFail
is
Create(F: in out FunctionWithDerivative;
Guess, Tolerance: Real;
NbIterations: Integer = 100)
---Purpose:
-- The Newton-Raphson method is done to find the root of the function F
-- from the initial guess Guess.The tolerance required on
-- the root is given by Tolerance. Iterations are stopped if
-- the expected solution does not stay in the range A..B.
-- The solution is found when abs(Xi - Xi-1) <= Tolerance;
-- The maximum number of iterations allowed is given by NbIterations.
returns FunctionRoot;
Create(F: in out FunctionWithDerivative;
Guess, Tolerance,A,B: Real;
NbIterations: Integer = 100)
---Purpose:
-- The Newton-Raphson method is done to find the root of the function F
-- from the initial guess Guess.
-- The tolerance required on the root is given by Tolerance.
-- Iterations are stopped if the expected solution does not stay in the
-- range A..B
-- The solution is found when abs(Xi - Xi-1) <= Tolerance;
-- The maximum number of iterations allowed is given by NbIterations.
returns FunctionRoot;
IsDone(me)
---Purpose: Returns true if the computations are successful, otherwise returns false.
---C++: inline
returns Boolean
is static;
Root(me)
---Purpose: returns the value of the root.
-- Exception NotDone is raised if the root was not found.
---C++: inline
returns Real
raises NotDone
is static;
Derivative(me)
---Purpose: returns the value of the derivative at the root.
-- Exception NotDone is raised if the root was not found.
---C++: inline
returns Real
raises NotDone
is static;
Value(me)
---Purpose: returns the value of the function at the root.
-- Exception NotDone is raised if the root was not found.
---C++: inline
returns Real
raises NotDone
is static;
NbIterations(me)
---Purpose: returns the number of iterations really done on the
-- computation of the Root.
-- Exception NotDone is raised if the root was not found.
---C++: inline
returns Integer
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;
TheRoot: Real ;
TheError: Real ;
TheDerivative: Real ;
NbIter: Integer;
end FunctionRoot;
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