[R] EXTERNAL: Re: subset with aggregate key

[Jesse Brown]

Matthew Dowle wrote:
> Hi,
>
> Try package 'data.table'. It has a concept of keys which allows you to do
> exactly that.
>
> http://datatable.r-forge.r-project.org/
>
> Matthew
>
>   
Hi Matthew,

Unfortunately, the load of that library fails (it builds successfully).
I'm currently looking into why. Error output looks something similar to:


 > library(data.table)
Error in .makeMessage(..., domain = domain, appendLF = appendLF) :
  could not find function "packageVersion"
Error : .onAttach failed in 'attachNamespace'
Error: package/namespace load failed for 'data.table'


I googled around a bit and there is mention of a bug in packageVersion 
but there was no solution that I found. Is this something that is easily 
overcome?


Thanks,

Jesse