Analytical term-structure fitting parameter \( \varphi(t) \). More...
#include <ql/models/shortrate/onefactormodels/hullwhite.hpp>
 Inheritance diagram for HullWhite::FittingParameter:
 Inheritance diagram for HullWhite::FittingParameter:| Public Member Functions | |
| FittingParameter (const Handle< YieldTermStructure > &termStructure, Real a, Real sigma) | |
|  Public Member Functions inherited from TermStructureFittingParameter | |
| TermStructureFittingParameter (const boost::shared_ptr< Parameter::Impl > &impl) | |
| TermStructureFittingParameter (const Handle< YieldTermStructure > &term) | |
|  Public Member Functions inherited from Parameter | |
| const Array & | params () const | 
| void | setParam (Size i, Real x) | 
| bool | testParams (const Array ¶ms) const | 
| Size | size () const | 
| Real | operator() (Time t) const | 
| const boost::shared_ptr< Impl > & | implementation () const | 
| const Constraint & | constraint () const | 
| Additional Inherited Members | |
|  Protected Member Functions inherited from Parameter | |
| Parameter (Size size, const boost::shared_ptr< Impl > &impl, const Constraint &constraint) | |
|  Protected Attributes inherited from Parameter | |
| boost::shared_ptr< Impl > | impl_ | 
| Array | params_ | 
| Constraint | constraint_ | 
Analytical term-structure fitting parameter \( \varphi(t) \).
\( \varphi(t) \) is analytically defined by
\[ \varphi(t) = f(t) + \frac{1}{2}[\frac{\sigma(1-e^{-at})}{a}]^2, \]
where \( f(t) \) is the instantaneous forward rate at \( t \).