vonBertalanffy {phaseR}

The von Bertalanffy growth model

Description

The derivative function of the von Bertalanffy growth model, an example of a one-dimensional autonomous ODE system.

Usage

vonBertalanffy(t, y, parameters)

Arguments

t

The value of t, the independent variable, to evaluate the derivative at. Should be a numeric vector of length one.

y

The value of y, the dependent variable, to evaluate the derivative at. Should be a numeric vector of length one.

parameters

The values of the parameters of the system. Should be a numeric vector with parameters specified in the following order: α, β.

Details

vonBertalanffy evaluates the derivative of the following ODE at the point (t, y):

dy/dt = αy^2/3 - βy.

Its format is designed to be compatible with ode from the deSolve package.

Value

Returns a list containing the values of the two derivatives at (t, x, y).

Author(s)

Michael J Grayling

See Also

ode