[R] for loop in nls function
Ingrid Tohver
itohver at u.washington.edu
Tue Apr 29 23:22:23 CEST 2008
Hello,
I am trying to apply a least squares non-linear regression to my
dataset, dem16. I can apply it to a subset based on a single site
fine, but I want to apply it to each (of 197) sites. I am stumbling
over a "for" loop. Site and Mean_Air are variables in my dataset and
I would like to estimate alpha, beta, gamma, mu and Tw for each site.
I have over 50,000 observations in my dataset.
results <- c()
for (i in Site) {
results[i]<- nls(Tw ~ mu + ((alpha - mu)/(1 + exp(gamma*(B -
Mean_Air)))),
data = dem16,
start = list(mu = 0.0001, alpha = 21.8, gamma = 0.22, B = 12.8))
}
Thank you in advance,
Ingrid
More information about the R-help
mailing list