> Here p[i] <- 1 - exp(-alpha*d^(-beta))> so, log(p[i]) produces NaNs when > exp(-alpha*d^(-beta)) is greater than 1.> How can I remove it.After > generating the out put we can omit it, but the> problem is different.
Wait... you're complaining that you can't take the natural log of a negative number in R? You can't do that anywhere. What do you expect to happen? The log of a negative number IS NaN. Sarah On Tue, Nov 29, 2011 at 6:28 PM, Gyanendra Pokharel <gyanendra.pokha...@gmail.com> wrote: > I have following code: > loglikelihood <- function(alpha,beta= 0.1){ > loglh<-0 > d<-0 > p<-0 > k<-NULL > data<-read.table("epidemic.txt",header = TRUE) > attach(data, warn.conflicts = F) > k <-which(inftime==1) > d <- (sqrt((x-x[k])^2+(y-y[k])^2))^(-beta) > p<-1 - exp(-alpha*d) > for(i in 1:100){ > if(i!=k){ > if(inftime[i]==0){ > loglh<-loglh +log(1-p[i]) > } > if(inftime[i]==2){ > loglh<-loglh + log(p[i]) > } > } > } > return(loglh) > } > Here p[i] <- 1 - exp(-alpha*d^(-beta)) > so, log(p[i]) produces NaNs when exp(-alpha*d^(-beta)) is greater than 1. > How can I remove it.After generating the out put we can omit it, but the > problem is different. > > On Tue, Nov 29, 2011 at 5:22 PM, Gyanendra Pokharel < > gyanendra.pokha...@gmail.com> wrote: > >> No, that,s not a problem Michael, >> I have following code: >> loglikelihood <- function(alpha,beta= 0.1){ >> loglh<-0 >> d<-0 >> p<-0 >> k<-NULL >> data<-read.table("epidemic.txt",header = TRUE) >> attach(data, warn.conflicts = F) >> k <-which(inftime==1) >> d <- (sqrt((x-x[k])^2+(y-y[k])^2))^(-beta) >> p<-1 - exp(-alpha*d) >> for(i in 1:100){ >> if(i!=k){ >> if(inftime[i]==0){ >> loglh<-loglh +log(1-p[i]) >> } >> if(inftime[i]==2){ >> loglh<-loglh + log(p[i]) >> } >> } >> } >> return(loglh) >> } >> Here p[i] <- 1 - exp(-alpha*d^(-beta)) >> so, log(p[i]) produces NaNs when exp(-alpha*d^(-beta)) is greater than 1. >> How can I remove it.After generating the out put we can omit it, but the >> problem is different. >> >> -- Sarah Goslee http://www.functionaldiversity.org ______________________________________________ R-help@r-project.org 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.