On Jun 27, 2013, at 4:14 AM, Charles Thuo wrote: > I run the following in the "actuar" package while trying to discretize the > lognormal distribution which i had fitted using the "fitdistrplus" package. > > fx <- discretize(plnorm(11.69,2.1),from = 0, to = 22, step = 0.5, method = > "upper") > Error in discretize(plnorm(11.69, 2.1), from = 0, to = 22, step = 0.5, : > 'cdf' must be a function or an expression containing 'x' > > Because of this error am unable to fit a compound distribution between the > negative binomial and lognormal. Is there another way besides using > "actuar".
The error is being thrown because you are not calling discretize with a function as its first argument. You are giving it a single value. Try: fx <- discretize( plnorm( x , 2.1), from = 0, to = 22, step = 0.5, method ="upper") You could also continue to emulate the first example on help(discretize) library(actuar) x <- seq(0, 22, 0.5) fu <- discretize(plnorm(x, 2.1), from = 0, to = 22, step = 0.5, method ="upper") fl <- discretize(plnorm(x, 2.1), from = 0, to = 22, step = 0.5, method ="lower") curve(plnorm(x, 2.1), xlim = c(0, 22)) par(col = "blue") plot(stepfun(head(x, -1), diffinv(fu)), pch = 19, add = TRUE) par(col = "green") plot(stepfun(x, diffinv(fl)), pch = 19, add = TRUE) par(col = "black") > I have just started using actuar. Kindly assist. Nothing to do with 'actuar' per se. The same error would ahveoccured with any R function that expects a function as its first argument. -- David Winsemius Alameda, CA, USA ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
