get_functions {nlstac} | R Documentation |
Get nonlinear functions from a separable nonlinear formula
Description
Returns the nonlinear functions of a formula
as charater strings.
Usage
get_functions(form, lp)
Arguments
form |
Either a string in the form |
lp |
A string array with the names of the linear parameters contained in the formula as obtained with |
Details
This is an internal function used by nls_tac
. A separable nonlinear formula is of the form
where ,...,
are general nonlinear functions,
,...,
, are the linear coefficients and
is the vector of nonlinear parameters.
The
formula
given in the input should be of this form and get_functions
will return an array with the string expressions of functions .
Value
An array containing the strings for the nonlinear functions of the formula.
Note
Also formulas of the form
could be given.
Author(s)
Mariano Rodríguez-Arias (arias@unex.es). Deptartment of Mathematics
Juan Antonio Fernández Torvisco (jfernandck@alumnos.unex.es). Department of Mathematics
University of Extremadura (Spain)
Rafael Benítez (rafael.suarez@uv.es). Department of Business Mathematics
University of Valencia (Spain)