initgompertz.exp: Function to generate initial values for parameter estimation

In grofit: The package was developed to fit fit many growth curves obtained under different conditions.

Description

The function receives time points, growth data, values for A, μ and λ and returns a list object which entrys are used as initial values in the nonlinear fit procedure nls. In this case the function is serve to define initial values for scaling parameter α and shifting parameter t_{shift}

Usage

initgompertz.exp(time, y, A, mu, lambda)

Arguments

time	Time points.
y	Growth data.
A	Maximum of the curve. If a vector is provided only the first entry is used.
mu	Maximum slope. If a vector is provided only the first entry is used.
lambda	Lag-phase. If a vector is provided only the first entry is used.

Value

A	Maximum of the curve.
mu	Maximum slope.
lambda	Lag-phase.
addpar	Two element vector defining scaling parameter α and shifting parameter t_{shift}.

See Also

gompertz.exp, gcFitModel

grofit documentation built on May 30, 2017, 4:08 a.m.