v<-frunge(t=seq(0,50,0.5), param=c(r=0.1,k=100), y0=3, Dfdt = dfdt, dt = 0.01, graph = TRUE)
plot(seq(0,50,0.5),v)
##
## Example of model fitting with frunge. a : determined initial condition
##
data(logis)
attach(logis)
nls(y~frunge(time,c(r,k),y0=3,dfdt,graph=FALSE),data=logis,start=list(r=0.05,k=100),trace=TRUE)->m1
plot(time,y)
lines(time,fitted(m1))
summary(m1)
detach(logis)
##
## Example of model fitting with frunge. b : unknown initial condition ;
## y0 is fitted as a parameter
data(logis)
attach(logis)
nls(y~frunge(time,c(r,k,y0),y0,dfdt,graph=FALSE),data=logis,start=list(r=0.05,k=100,y0=y[1]),
trace=TRUE)->m2
plot(time,y)
lines(time,fitted(m2))
summary(m1)
detach(logis)
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