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-- File: BissecNewton.cdl
-- Created: Tue 14 10:42:34 1991
-- Author: Laurent PAINNOT
-- <lpa@topsn3>
---Copyright: Matra Datavision 1991, 1992
class BissecNewton from math
---Purpose:
-- This class implements a combination of Newton-Raphson and bissection
-- methods to find the root of the function between two bounds.
-- Knowledge of the derivative is required.
uses Vector from math,
Matrix from math,
FunctionWithDerivative from math,
Status from math,
OStream from Standard
raises NotDone from StdFail
is
Perform(me: in out; F: out FunctionWithDerivative;
Bound1, Bound2: Real;
NbIterations: Integer)
is static protected;
Create(F: in out FunctionWithDerivative;
Bound1, Bound2, TolX: Real;
NbIterations: Integer = 100)
---Purpose:
-- A combination of Newton-Raphson and bissection methods is done to find
-- the root of the function F between the bounds Bound1 and Bound2.
-- on the function F.
-- The tolerance required on the root is given by TolX.
-- The solution is found when :
-- abs(Xi - Xi-1) <= TolX and F(Xi) * F(Xi-1) <= 0
-- The maximum number of iterations allowed is given by NbIterations.
returns BissecNewton;
IsSolutionReached(me: in out; F: out FunctionWithDerivative)
---Purpose:
-- This method is called at the end of each iteration to check if the
-- solution has been found.
-- It can be redefined in a sub-class to implement a specific test to
-- stop the iterations.
returns Boolean
is virtual;
IsDone(me)
---Purpose: Tests is the root has been successfully found.
---C++: inline
returns Boolean
is static;
Root(me)
---Purpose: returns the value of the root.
-- Exception NotDone is raised if the minimum 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 minimum 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 minimum was not found.
---C++: inline
returns Real
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 redifine the operator <<.
is static;
fields
Done: Boolean;
TheStatus: Status is protected;
XTol: Real is protected;
x: Real is protected;
dx: Real is protected;
f: Real is protected;
df: Real is protected;
end BissecNewton;
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