Displaying 1 result from an estimated 1 matches for "meandepth_m".
2010 Oct 13
2
Using NLS with a Kappa function
...ying to use NLS to fit a dataset using a Kappa function, but I am
having problems. Depending on the start values that I provide, I get
either:
Error in numericDeriv(form[[3L]], names(ind), env) :
Missing value or an infinity produced when evaluating the model
Or
Error in nls(FldFatRate ~ funct3(MeanDepth_m, h, k, z, a), data = data1, :
singular gradient
I think these error results from the fact that I obtained a good fit with a
logistic function and that the Kappa reduces to a logistic in the limit with
k -> 0. This causes a problem because the Kappa function has a term raised
to (1/k)th power le...