QuantLib: LevenbergMarquardt Class Reference

A free/open-source library for quantitative finance Reference manual - version 1.20

Public Member Functions | List of all members
LevenbergMarquardt Class Reference
Math tools » Optimizers

Levenberg-Marquardt optimization method. More...

`#include <ql/math/optimization/levenbergmarquardt.hpp>`

Inheritance diagram for LevenbergMarquardt:
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## Public Member Functions
| LevenbergMarquardt (Real epsfcn=1.0e-8, Real xtol=1.0e-8, Real gtol=1.0e-8, bool useCostFunctionsJacobian=false)
virtual EndCriteria::Type | minimize (Problem &P, const EndCriteria &endCriteria)
| minimize the optimization problem P
virtual Integer | getInfo () const
void | fcn (int m, int n, Real *x, Real *fvec, int *iflag)
void | jacFcn (int m, int n, Real *x, Real *fjac, int *iflag)

## Detailed Description

Levenberg-Marquardt optimization method.

This implementation is based on MINPACK (http://www.netlib.org/minpack, http://www.netlib.org/cephes/linalg.tgz) It has a built in fd scheme to compute the jacobian, which is used by default. If useCostFunctionsJacobian is true the corresponding method in the cost function of the problem is used instead. Note that the default implementation of the jacobian in CostFunction uses a central difference (oder 2, but requiring more function evaluations) compared to the forward difference implemented here (order 1).

Examples
  BermudanSwaption.cpp, and Gaussian1dModels.cpp.