On Wed, 23 Jul 2003, Deborah Swayne wrote: > Has anyone else seen this behavior from the "maps" package? > > map('state', fill=TRUE) > > results in a lively mix of overlapping polygons inside a > map of the US, but they have no obvious relationship to > state boundaries. (See attached jpeg.)
Yes, this replicates. I think the trouble is in the part of map() where it makes a polygon of the lines: if (fill) { gonsize <- line$size color <- rep(color, length = length(gonsize)) keep <- !is.na(color) coord[c("x", "y")] <- makepoly(coord, gonsize, keep) color <- color[keep] } and I think makepoly needs gon, not gonsize, as an argument, to stitch the boundary lines together in the correct order - the "interesting" effect seems to come from some lines not being reversed. Unfortunately, I don't have archival copies of earlier map() functions to check this - it could also be in mapgetl(): if (fill) coord <- mapgetl(database, line$number, xlim, ylim) although this is less likely, because the same function is used to retrieve the same data when fill=FALSE too. Something has got lost in building the polygons, it seems! As far as I can establish, fill=TRUE did work in earlier versions. > p <- map('state', region=c('penn'), resolution=0) > plot(p, type="l") gives the boundaries in both cases, > pf <- map('state', region=c('penn'), fill=TRUE, resolution=0) gives black/white "interesting" polygons, and > plot(pf, type="l") draws the boundary lines with wrong links to next line segents. Roger -- 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