R/gompertz.exp.R

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

gompertz.exp <-
function (time, A,mu,lambda,addpar)
{
A      <- A[1]
mu     <- mu[1]
lambda <- lambda[1]
alfa   <- addpar[1]
tshift <- addpar[2]

if (is.numeric(time)==FALSE) stop("Need numeric vector for: time")
if (is.numeric(mu)==FALSE) stop("Need numeric vector for: mu")
if (is.numeric(lambda)==FALSE) stop("Need numeric vector for: lambda")
if (is.numeric(A)==FALSE) stop("Need numeric vector for: A")
if (is.numeric(alfa)==FALSE) stop("Need numeric vector for: addpar[1]")
if (is.numeric(tshift)==FALSE) stop("Need numeric vector for: addpar[2]")

e            <- exp(1)
y            <- A*exp(-exp(mu*e*(lambda-time)/A +1.0)) + A*exp(alfa*(time-tshift))
gompertz.exp <- y
}