Displaying 2 results from an estimated 2 matches for "powrdpltinit".
2010 Apr 15
0
nlsList {nlme} - control arguments problem
...nds on
the parameter space duirng an nlsList fit. He suggested using optim to optimize
the parameters prior to each fit. This worked well for me as I had a customized
selfStart function that then optimized the parameters for each individual
separately.
if you rewrote your selfStart function as:
powrDpltInit <-
function(mCall, LHS, data) {
xy <- sortedXyData(mCall[["x"]],LHS,data)
min.s <- min(y)
dif.s <- max(y)-min(y)
dplt.s <- 0.5
p.s <- -.20
value <- c(min.s, dplt.s, dif.s, p.s)
#function to optimize
func1 <- function(value) {
min...
2009 Jun 29
0
nlsList {nlme} - control arguments problem
...?.. ..$ maxiter ?: num 100
?.. ..$ tol ? ? ?: num 1e-05
?.. ..$ minFactor: num 0.000977
?.. ..$ printEval: logi FALSE
?.. ..$ warnOnly : logi FALSE
?.. ..$ algorithm: chr "port"
?.. ..$ lower ? ?: num [1:4] 0 0 0 -10
If it helps, here's the selfStart function that I'm using....
powrDpltInit <-
function(mCall, LHS, data) {
? xy ? ? <- sortedXyData(mCall[["x"]],LHS,data)
? min.s ?<- min(y)
? dif.s ?<- max(y)-min(y)
? dplt.s <- 0.5
? p.s ? ?<- -.20
? value ?<- c(min.s, dplt.s, dif.s, p.s)
? names(value) <- mCall[c("min","dplt","d...