selfStart for the beta growth function

Description

Implements some self starting rules for the beta growth function as desribed by Yin et. al (2003). This is equation 2.5 in the paper referenced below (Archontoulis and Miguez).

Usage

1
SSbgf(time, w.max, t.e, t.m)

Arguments

time

a numeric vector of values at which to evaluate the model. This is typically expressed in some measure of time.

w.max

A numeric parameter representing the maximum weight (or biomass).

t.e

A numeric parameter representing the time at which maximum weight is attained (w.max).

t.m

A numeric parameter representing the time at which the inflection point of the curve is attained. The maximum growth rate ocurrs at this time.

Value

returns a numeric vector of the same length as the input

Author(s)

Fernando E. Miguez

References

Yin, X., J. Goudriaan, E.A. Lantinga, J. Vos, and J.H.J. Spiertz. 2003b. A flexible sigmoid function of determinate growth. Annals of Botany 91: 361–371. (with erratum in Annals of Botany 91: 753, 2003).

Nonlinear Regression Models and Applications in Agricultural Research. Sotirios V. Archontoulis and Fernando E. Miguez. Agronomy Journal. doi: 10.2134/agronj2012.0506

Examples

1
## See the vignette for an example