Great! Thank you for your help! -Charlotte
>> >> On Mon, Apr 26, 2010 at 1:12 AM, Tal Galili <tal.gal...@gmail.com> wrote: >>> >>> mm... >>> I also noticed the function you wrote didn't use parenthesis, mixed b and c >>> and used different names for K. >>> Your code is a great exercise in debugging (no offense intended :) ) >>> Try using: >>> bird<-bird.density[0] # I assume this exists >>> eqn<- function(K1, b1 = 1.22, c1 = .55) { >>> b<-1.22 >>> c<-0.55 >>> bird <- c1*bird + b1*bird*(1-b1*bird)*bird/K1 >>> return(bird) >>> } >>> >>> k1<-optim(c(0,10),eqn) >>> >>> >>> >>> ----------------Contact >>> Details:------------------------------------------------------- >>> Contact me: tal.gal...@gmail.com | 972-52-7275845 >>> Read me: www.talgalili.com (Hebrew) | www.biostatistics.co.il (Hebrew) | >>> www.r-statistics.com (English) >>> ---------------------------------------------------------------------------------------------- >>> >>> >>> >>> >>> On Mon, Apr 26, 2010 at 11:08 AM, Tal Galili <tal.gal...@gmail.com> wrote: >>>> >>>> Hi Charlotte , >>>> I can't reproduce your code, but skimming through it - >>>> It would appear that: >>>> 1) in >>>> eqn1<- function(K1, bird) >>>> you didn't define "bird" (you did define it before the function, so I'd >>>> suggest just removing it from the function call like this: >>>> eqn1<- function(K1) >>>> 2) you didn't "return" and value at the end of the function. >>>> 3) you use different name in optim then in the function you made. >>>> 4) I see no point for you to use the for loop. >>>> >>>> >>>> Consider trying the following code: >>>> b<-1.22 >>>> c<-0.55 >>>> bird<-bird.density[0] # I assume this exists >>>> eqn<- function(K1, bird) { >>>> b<-1.22 >>>> c<-0.55 >>>> bird <- 0.55*bird + b*bird*1-b*bird*bird/K >>>> return(bird) >>>> } >>>> >>>> k1<-optim(c(0,10),eqn) >>>> >>>> >>>> ----------------Contact >>>> Details:------------------------------------------------------- >>>> Contact me: tal.gal...@gmail.com | 972-52-7275845 >>>> Read me: www.talgalili.com (Hebrew) | www.biostatistics.co.il (Hebrew) | >>>> www.r-statistics.com (English) >>>> ---------------------------------------------------------------------------------------------- >>>> >>>> >>>> >>>> >>>> On Mon, Apr 26, 2010 at 9:00 AM, Charlotte Chang <c.h.w.ch...@gmail.com> >>>> wrote: >>>>> >>>>> optim >>> >> > ______________________________________________ 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.