[R] Fwd: Simulate nested data

Sarah Goslee sarah.goslee at gmail.com
Fri Nov 9 20:40:00 CET 2012


Andrea,

I simply meant that I couldn't run your code assigning a value to
species$groups
because the code didn't include any information about creating the R
object species. Thus, I changed the name of that R object to
speciesgroups and altered your code so that it runs by removing the
erroneous c().

Did you try my suggestion, and did or did it not help your problem?

Sarah

On Fri, Nov 9, 2012 at 2:37 PM, Andrea Goijman
<agoijman at cnia.inta.gov.ar> wrote:
> Hi Sarah,
>
> Maybe I expressed myself wrong, but so far, I don't have the species; I'm
> just wanting to generate simulated data. For example, creating an unbalanced
> (and random) number of species per group, and then run the for-loops
>
> for example:
> Group1: 3 species
> Group2: 5 species
> Group3: 8 species
>
> then, I want to create an array "p" to be able to fill the following loop
>
> for (g in 1:groups){
>            for (i in 1:species[g]){
>                p[i] <- rnorm(1, mu.p[g], tau.p[g])
>      }#species
> }
>
>
> Andrea
>
>
>
>
> On Fri, Nov 9, 2012 at 2:26 PM, Sarah Goslee <sarah.goslee at gmail.com> wrote:
>>
>> Hi Andrea,
>>
>> Without knowing what species is, I can't run your code as is, but try
>> this:
>>
>>
>> groups<-3
>> speciesgroups <- as.integer(runif(groups,1,10))
>> # I'd use sample(1:10, groups, replace=TRUE)
>> p<-array(NA,dim=speciesgroups)
>>
>>
>> Mostly you're trying to use c() on something that's already a vector.
>>
>> Sarah
>>
>> On Fri, Nov 9, 2012 at 2:16 PM, Andrea Goijman
>> <agoijman at cnia.inta.gov.ar> wrote:
>> > I know this seems like a very easy question (and maye it is) but I've
>> > been
>> > trying to simulate nested data and been unsucessful so far..
>> >
>> > I want to simulate a varying number of species within a group; and then
>> > create an array to store the results of my for-loop. For example:
>> >
>> > groups<-3
>> > species$groups<-as.integer(runif(groups,1,10))  #species per functional
>> > group
>> >
>> > ###create arrays to store results
>> >
>> > p<-array(NA,dim=c(species$groups))
>> >
>> > So, far this is not working...
>> >
>> > Thanks!
>>
>>

Sarah Goslee
http://www.functionaldiversity.org




More information about the R-help mailing list