findRoots {drgee}

Non Linear Equation System Solving

Description

A wrapper around nleqslv from the nleqslv package to solve a non linear system of equations.

Usage

findRoots(beta.init, eq.func, d.eq.func = NULL, arg.list, ...)

Arguments

beta.init

An initial guess for the zero.

eq.func

A function of two variables for which the zero are sought. Its first argument beta should be a vector over which the zeros are sought and the second argument arg.list a list of additional arguments.

d.eq.func

A function to return the Jacobian of eq.func taking the same arguments as eq.func. Supplying this function can speed up calculations. Default is NULL.

arg.list

The second argument to eq.func and d.eq.func

...

A list of additional arguments to be passed to nleqslv

Details

findRoots calculates zeros fo the function eq.func and is the default equation solving function in drgee. It is supplied as a separate function in order to allow users to use other equation solvers by writing their own wrapper with the same interface as findRoots.

Value

The value is a list containing the following arguments:

roots

The zero(s) of the function eq.func.

optim.object

The optimization object returned from nleqslv.

Author(s)

Johan Zetterqvist, Arvid Sjölander

See Also

nleqslv in package nleqslv.