On Mon, 25 Aug 2003, Thomas Petzoldt wrote: > Barry Rowlingson wrote: > > > Howabout this i just bashed up from a quick search: > > > > boundaryFill <- function(mat, x,y,fill,boundary) > > [...] > > > note it fills 4-connected regions. I wouldnt like to do it on anything > > complex since it'll be awful slow.... > > Yes, this is in principle the same solution I use during aan external C > function. However, the problem is not only speed, but the large amount > of stack memory with larger matrices (say 100 x 100) due to recursion, > no matter if I use options(expression = large_value) or not. >
A very powerful tool is grdmask in GMT (http://gmt.soest.hawaii.edu/) followed by grd2xyz to create something easier to read (possibly as binary through connections). It is well-proven, and handles large grids comfortably. Roger Bivand Economic Geography Section, Department of Economics, Norwegian School of Economics and Business Administration, Breiviksveien 40, N-5045 Bergen, Norway. voice: +47 55 95 93 55; fax +47 55 95 93 93 e-mail: [EMAIL PROTECTED] ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help
