saemix (version 3.3)

plot,SaemixModel,ANY-method: Plot model predictions using an SaemixModel object

Description

This function will plot predictions obtained from an SaemixModel object over a given range of X. Additional predictors may be passed on to the function using the predictors argument.

Usage

# S4 method for SaemixModel,ANY
plot(x, y, range = c(0, 1), psi = NULL, predictors = NULL, ...)

Arguments

x

an SaemixData object or an SaemixSimData object

y

unused, present for compatibility with base plot function

range

range of X over which the model is to be plotted. Important note: the first predictor will be used for the X-axis, the other predictors when present need to be passed sequentially in the predictors argument, in the order in which they appear in the model Less important note: please use explicitely range=XXX where XXX is of the form c(a,b) to pass the plotting range on the X-axis)

psi

parameters of the model

predictors

additional predictors needed to pass on to the model

...

additional arguments to be passed on to plot (titles, legends, ...). Use verbose=TRUE to print some messages concerning the characteristics of the plot

Examples

# Note that we have written the PK model so that time is the first predictor (xidep[,1]) 
# and dose the second
model1cpt<-function(psi,id,xidep) { 
     tim<-xidep[,1]  
     dose<-xidep[,2]
     ka<-psi[id,1]
     V<-psi[id,2]
     CL<-psi[id,3]
     k<-CL/V
     ypred<-dose*ka/(V*(ka-k))*(exp(-k*tim)-exp(-ka*tim))
     return(ypred)
     }
 x<-saemixModel(model=model1cpt,description="One-compartment model with first-order absorption", 
               psi0=matrix(c(1.5,30,1), ncol=3,byrow=TRUE, dimnames=list(NULL, c("ka","V","CL"))))
 # Plot the model over 0-24h, using the parameters given in psi0 and a dose of 300
 plot(x, range=c(0,24), predictors=300, verbose=TRUE)
 # Plot the model over 0-24h, using another set of parameters and a dose of 350
 plot(x, range=c(0,24), psi=c(1.5,20,2), predictors=350, verbose=TRUE)