search for: fitta

Displaying 1 result from an estimated 1 matches for "fitta".

Did you mean: gitta
2012 Aug 23
1
NLS bi exponential Fit
Hi everyone, I'm trying to perform a bi exponential Fit with the package NLS. the plinear algorithm seems to be a good choice see: p<-3000 q<-1000 a<--0.03 b<--0.02 t<-seq(0:144);t y<-p*exp(a*t) + q*exp(b*t)+rnorm(t,sd=0.3*(p* exp(a*t) + q*exp(b*t))) fittA <- nls(y~cbind(exp(a*t), exp(b*t)), algorithm="plinear",start=list(a=-.1, b=-0.2), data=list(y=y, t=t), trace=FALSE);fittA # a b .lin1 .lin2 # -0.003074 -2.777 4512 -2399 fittB <- nls(y~cbind(exp(a*t), exp(b*t)), algorithm="plinear&quo...