> "determine the largest concentration of members in the smallest radius"
I haven't read the whole thread, and I'm not familiar with this topic. However, looking at it from an intuitive perspective, isn't the smallest radius zero. If the concentration means the number of "members" divided by the area... ...then would the largest concentration be undefined, merely because of division by zero. Perhaps your question is a valid one. But if you're wanting a large pool of people to consider helping, I'd recommend a more (mathematically) precise definition of the problem you're trying to solve. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.