I would like to fit the curves on a number of data sets grouped by processing. This works very well with nlslist, but now I would like to introduce upper bounds for my parameters.
Bounding works very well when I put each group separately using nls, but apparently not when I want to speed up my work (I have many other datasets) with nlslist.
Can someone help me here with any idea how to solve this?
An example of my dataset:
DF1<-data.frame(treatment = rep(c("mineral","residues"),4),
N_level = c(0,0,100,100,200,200,300,300),
yield = c(8,8.5,10,10.5,11,9.8,9.5,9.7))
Df1
treatment N_level yield
1 mineral 0 8.0
2 residues 0 8.5
3 mineral 100 10.0
4 residues 100 10.5
5 mineral 200 11.0
6 residues 200 9.8
7 mineral 300 9.5
8 residues 300 9.7
Trying to fit this dataset with nls only works well:
fit_mineral <- nls(formula = yield ~ a + b*0.99^N_level +c*N_level,
data=subset(DF1, subset = treatment == "mineral"),
algorithm = "port", start = list(a = 12, b = -8, c= -0.01),
upper = list(a=1000, b=-0.000001, c=-0.000001))
fit_mineral
Nonlinear regression model
model: yield ~ a + b * 0.99^N_level + c * N_level
data: subset(DF1, subset = treatment == "mineral")
a b c
13.7882 -5.8685 -0.0126
residual sum-of-squares: 0.4679
But as soon as I try to combine things in nlslist, it does not work:
fit_mineral_and_residues <- nlsList(model = yield ~ a + b*0.99^N_level +c*N_level
| treatment, data=DF1,
algorithm = "port", start = list(a = 12, b = -8, c= -0.01),
upper = list(a=1000, b=-0.000001, c=-0.000001))
error message:
Error in nlsList(model = yield ~ a + b * 0.99^N_level + c * N_level | :
unused arguments (algorithm = "port", upper = list(a = 1000, b = -1e-06, c = -1e-06))