On Thu, 25 Aug 2005, Anna Oganyan wrote: > Hello, > I am quite new in R, and I have one problem: > I have large d-dimensional data sets (d=2, 3, 6, 10). I would like to > divide the d-dim space into n (n may be 10, but better some larger > number, for example 20) equally sized d-dim hypercubes and count how > many data points are in each cube. Is there any way to do it quickly, I > mean - in a reasonable time? Actually, I want to get some rough idea > of underlying densities of these data and compare them. > Thanks a lot! > Anna
How do you divide a 10D space into 10 hypercubes? You need at least some of dimensions to be undivided. The general idea is easy: apply cut() to each dimension, so your dimensions become factors, then table() will produce the counts. That will be quick enough for millions of points. -- Brian D. Ripley, [EMAIL PROTECTED] Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595 ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html