LDEsysMat {nlme} | R Documentation |
Generate the system matrix for the linear differential equations determined by a compartment model.
LDEsysMat(pars, incidence)
pars |
a numeric vector of parameter values. |
incidence |
an integer matrix with columns named From ,
To , and Par . Values in the Par column must
be in the range 1 to length(pars) .
Values in the From
column must be between 1 and the number of compartments.
Values in the To
column must be between 0 and the number of compartments. |
A compartment model describes material transfer between k
in a system of k
compartments to a linear system of differential
equations. Given a description of the system and a vector of parameter
values this function returns the system matrix.
This function is intended for use in a general system for solving compartment models, as described in Bates and Watts (1988).
A k
by k
numeric matrix.
Douglas Bates bates@stat.wisc.edu
Bates, D. M. and Watts, D. G. (1988), Nonlinear Regression Analysis and Its Applications, Wiley, New York.
# incidence matrix for a two compartment open system incidence <- matrix(c(1,1,2,2,2,1,3,2,0), ncol = 3, byrow = TRUE, dimnames = list(NULL, c("Par", "From", "To"))) incidence LDEsysMat(c(1.2, 0.3, 0.4), incidence)