[R] how to restrict a parameter in optim()

Dear all, I'm trying to estimate some parameters with the optim() function but I need to restrict one parameter and I have not found how to do it. Could you help me please? my program is basically fn<-function(s) initial<-function(r) { cst<-r[1] cst1<-r[2] beta<-r[3] rho<-r[4] p1<-r[5] return

[R] how to restrict a parameter in optim()

Dear all, I'm trying to estimate some parameters with the optim() function but I need to restrict one parameter and I have not found how to do it. Could you help me please? my program is basically fn<-function(s) initial<-function(r) { cst<-r[1] cst1<-r[2] beta<-r[3] rho<-r[4] p1<-r[5] r