nls: Loop and break in a decided number of iterations - r

Question

I've like two make to sequential operations:
1) Ajusted two nls models in a subset; and
2) Loop the models just a number of iteracions =1.
For the first step I make:
#Packages
library(minpack.lm)
# Data set - Diameter in function of Feature and Age
Feature<-sort(rep(c("A","B"),22))
Age<-c(60,72,88,96,27,
36,48,60,72,88,96,27,36,48,60,72,
88,96,27,36,48,60,27,27,36,48,60,
72,88,96,27,36,48,60,72,88,96,27,
36,48,60,72,88,96)
Diameter<-c(13.9,16.2,
19.1,19.3,4.7,6.7,9.6,11.2,13.1,15.3,
15.4,5.4,7,9.9,11.7,13.4,16.1,16.2,
5.9,8.3,12.3,14.5,2.3,5.2,6.2,8.6,9.3,
11.3,15.1,15.5,5,7,7.9,8.4,10.5,14,14,
4.1,4.9,6,6.7,7.7,8,8.2)
d<-dados <- data.frame(Feature,Age,Diameter)
str(d)
#Create a nls model (Levenberg-Marquardt algoritm) for each Feature (A abd B)
e1<- Diameter ~ a1 * Age^a2
Fecture_vec<-unique(d$Feature)
mod_ND <- list() #List for save each model
for(i in 1:length(Fecture_vec)){
d2 <- subset(d, d$Feature == Fecture_vec[i])
mod_ND[[i]] <- nlsLM(e1, data = d2,
start = list(a1 = 0.1, a2 = 10),
control = nls.control(maxiter = 1000))
print(summary(mod_ND[[i]]))
}
#
Here, so far so good, but if I try to make a loop with 999 simulation and recycle the start values with coef(mod_ND[[i]])[1] and coef(mod_ND[[i]])[2] and stop when number of iterations is 1:
e1<- Diameter ~ a1 * Age^a2
Fecture_vec<-unique(d$Feature)
mod_ND <- list() #List for save each model
for(i in 1:length(Fecture_vec)){
d2 <- subset(d, d$Feature == Fecture_vec[i])
mod_ND[[i]] <- nlsLM(e1, data = d2,
start = list(a1 = 0.1, a2 = 10),
control = nls.control(maxiter = 1000))
Xs<-data.frame()
for(z in 1:999){
d2 <- subset(d, d$Feature == Fecture_vec[i])
mod_ND[[z]] <- nlsLM(e1, data = d2,
start = list(a1 = coef(mod_ND[[i]])[1], a2 = mod_ND[[i]])[2]),
control = nls.control(maxiter = 1000))
if (mod_ND[[z,c(finIter")]] <= 1){ break } ## Stop when iteractions =1
print(summary(mod_ND[[z]]))
}
}
#
Doesn't work!! Please any ideas?

Answer 1

#Packages
library(minpack.lm)
library(dplyr)
m<-function(d, a=0.01,b=10){
mod<- nlsLM(Diameter ~ a1 * Age^a2,start = list(a1 = a, a2 = b),control = nls.control(maxiter = 1000), data = d)
par1<- summary(mod)$coefficients[[1]]
par2 <- summary(mod)$coefficients[[2]]
print(summary(mod))
if(mod$convInfo[["finIter"]]>1){
m(d,par1,par2)
}else{
print(" --------Feature B-----------")
}
}
list_models <- dlply(d,.(Feature),m)
list_models