First-order Compartment Model

DESCRIPTION:

This selfStart model evaluates the first-order compartment function and its gradient. It has an initial attribute that will evaluate initial estimates of the parameters lKe, lKa, and lCl for a given set of data.

USAGE:

SSfol(Dose, input, lKe, lKa, lCl) 

REQUIRED ARGUMENTS:

Dose
a numeric value representing the initial dose.
input
a numeric vector at which to evaluate the model.
lKe
a numeric parameter representing the natural logarithm of the elimination rate constant.
lKe
a numeric parameter representing the natural logarithm of the absorption rate constant.
lCl
a numeric parameter representing the natural logarithm of the clearance.

VALUE:

a numeric vector of the same length as input. It is the value of the expression `Dose*exp(lKe+lKa-lCl)*(exp(-exp(lKe)*input) - exp(-exp(lKa)*input))/(exp(lKa) - exp(lKe))'. If all of the arguments lKe, lKa, and lCl are names of objects, the gradient matrix with respect to these names is attached as an attribute named gradient .

SEE ALSO:

,

EXAMPLES:

Theoph.1 <- Theoph[ Theoph$Subject == 1, ] 
SSfol( Theoph.1$Dose, Theoph.1$Time, -2.5, 0.5, -3 )  # response only 
lKe <- -2.5 
lKa <- 0.5 
lCl <- -3 
SSfol( Theoph.1$Dose, Theoph.1$Time, lKe, lKa, lCl ) # response and gradient