Re: [R] - counting factor occurrences within a group: tapply()

Jim- That did the trick- thanks so much for taking the time to help me out. Sincerely, Ian Chidister On Wed, Jul 29, 2009 at 11:57 AM, Ian Chidister wrote: > Dear List, > > I'm an [R] novice starting analysis of an ecological dataset containing the > basal areas of different

Re: [R] - counting factor occurrences within a group: tapply()

Hi All- Thanks for your quick responses. I was looking for unique instances, so Jim's and Daniel's suggestions got the job done. Using "length" alone didn't discriminate between multiple occurrences of the same species and multiple species. I do have one followup question- my full data set (not

[R] - counting factor occurrences within a group: tapply()

hat this occurs because R does not subset factor levels, but I'm wondering if there's a simple way around this. Thanks for your help, Ian Chidister Environment and Resources The Nelson Institute for Environmental Studies University of Wisconsin-Madison, USA [[alternative HTML