On Thu, 7 Dec 2006, Ross Boylan wrote: > I'd like to evaluate a function at each point on a 2 or 3-D grid. Is > there some function that already does this, or generates the grid of > points? > > My search has led me to the grid and lattice packages, and I found a > reference to the sp package (e.g., SpatialGrid) for this. There are > things in there that might be relevant, but at first blush many of them > are embedded in other concepts (grobs, shingles, rugs) and don't > obviously solve the problem. > > I know this is not a hard thing to program, but I suspect someone has > already done it. Any pointers?
Which "space" are your points in? The sp package might help if the data are spatial/geographical, but I think that expand.grid() is your friend, followed by one of the apply() family to run your function on each row of the data frame output by expand.grid(). Roger > > Thanks. > -- Roger Bivand Economic Geography Section, Department of Economics, Norwegian School of Economics and Business Administration, Helleveien 30, N-5045 Bergen, Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43 e-mail: [EMAIL PROTECTED] ______________________________________________ [email protected] mailing list 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.
